HK1176520A - Systems and methods for maintaining perishable foods - Google Patents

Description

System and method for maintaining perishable food items

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the right of U.S. provisional patent application No. 61/____, ____, filed on even 10/30 of 2009, converted from U.S. utility application No. 12/610,126, and U.S. provisional patent application No. 61/256,868 filed on even 10/30 of 2009, both of which are incorporated herein by reference in their entirety.

Technical Field

The present invention relates to a system and method for increasing the shelf life of oxidatively degradable foodstuffs, such as fresh fish.

Background

Oxidizable and decomposable foods such as fish, meat, poultry, baked goods, fruits, grains and vegetables have a limited shelf life in normal atmospheric conditions. The oxygen levels present in normal atmospheric environments can cause changes in odor, aroma, color, and texture, resulting in overall deterioration of food quality due to chemical effects or the growth of aerobic spoilage microorganisms.

Modified Atmosphere Packaging (MAP) has been used to improve shelf life and safety of stored food by inhibiting spoilage organisms and pathogens. MAP is a single gas or a mixture of gases that replaces the normal atmospheric environment in a food storage package. The gas used in MAP is most often oxygen (O)₂) Nitrogen (N)₂) And carbon dioxide (CO)₂) Combinations of (a) and (b). In most cases, by lowering O₂Concentration and increase of CO₂The concentration combination obtains the bacteriostatic effect. Farber J.M. (Farber, J.M.)1991. microbial aspects of modified atmosphere packaging technology: review (microbiological plastics of modified-moved packaging technology: a review.) journal of food protection (j.food technology) 54: 58-70.

In conventional MAP systems, the MAP gas composition is not manipulated after the initial replacement of the normal atmospheric environment. Thus, the composition of the gas present in the food package may change over time. Changes in the gas portion of the packaging can be caused by gas diffusion into and out of the product, gas diffusion into and out of the food packaging, and microbial metabolic effects. In some casesIn case, the food will absorb carbon dioxide (CO)₂) Thereby reducing CO in the gas portion of the package₂While the relative amount of other gases (e.g., oxygen) is increased. Carbon dioxide absorption can create a negative pressure in the shipping bag, creating an "evacuated" condition that can potentially damage food by, for example, reducing the carbon dioxide concentration below a level effective to inhibit microbial spoilage of the food while correspondingly increasing the residual oxygen concentration. From CO₂The vacuum created by absorption can also cause leaks (especially in rigid shipping bags) leading to their failure.

MAP systems and related techniques have been used to transport and store food. However, these systems have considerable limitations for the delivery of foods that are sensitive to oxidative decomposition (e.g., fish). First and foremost, the cooling and oxygen removal processes of these systems are integrated into a single sealed container (typically a refrigerated freight container-refrigeration unit) so that upon opening, the entire load is exposed to ambient atmospheric conditions. This limits the ability to distribute food to different delivery locations and typically requires the purchaser to purchase all of the product after opening. Second, the integration of the oxygen removal process into the container determines that inadvertent or premature breaking of the seal in the sealed container can compromise the overall product. Third, integrating the oxygen removal process into the freight container does not allow for isolated air conditions within the container during storage and/or transport, thereby limiting the flexibility of the process. Fourth, sealing of freight containers is particularly difficult when the atmospheric pressure within the container becomes less than the pressure outside the container. The most common MAP application employs a bag-in-box (bag-in-box) configuration, wherein the perishable is contained within a bag/package, which is in turn contained within a box/carton. The bag/package is flushed with gas one or more times to create the desired modified atmosphere, and then the bag/package is heat sealed and the box is closed. The system may or may not employ excess headspace to allow for absorption of, for example, CO by many perishables₂Waiting for excessive filling of gas. A typical limitation on how much excess amount of headspace can be employed is the requirement that these MAP packages be integrated (stacked) for shipping and disposal. The structural constraint determines the outer carton or boxThe entire supply chain can be closed and stacked around the bags/packages and easily disposed of. Thus, designing "excess" headspace into these frameworks is not sufficient to prevent CO₂A decrease in partial pressure over time and a corresponding increase in oxygen.

In addition to the conventional MAP system discussed above, systems for transporting perishable food using an external fuel cell to remove oxygen have been developed, such as disclosed by U.S. patent No. 6,179,986. This patent does not address the use of fuel cells, but rather discloses the use of a solid polymer Electrolyte (EOC) electrochemical oxygen control system based on Proton Exchange Membrane (PEM) stacks, which operate differently from fuel cells and require the application of a DC power source. The PEM is operated outside the sealed container such that it requires the discharge of at least one reaction product of the fuel cell outside the sealed container. In addition, the system described in the' 986 patent requires the use of a dedicated power source to power the fuel cell.

The system set forth above has a number of disadvantages which make it undesirable for long term transport or storage of oxidatively degradable foodstuffs. Accordingly, there is a need for an improved system that will increase the shelf life of the oxidatively decomposable material during transportation and storage that can avoid the disadvantages of conventional shipping and storage techniques. In addition, it advantageously has the ability to transport and then retrieve modular packages of transported food at different destinations without disrupting the preservation environment of the package.

Moreover, these configurations, which are generally small in size, are typically defined as being disposable (multiple gas flushing events) because they do not have any valves or fittings that facilitate the initial gas flushing or additional gas flushing after the initial gas flushing process. Furthermore, multiple gas flushes are not economically feasible due to the necessity of reasonable throughput requirements. Since these configurations are typically small packages (typically 40 pounds or less) that are easy to handle, the cost per pound with a MAP process is extremely high and the resulting MAP gas mixture is not ideal for maximizing shelf life.

An improvement over the above configuration is disclosed in U.S. patent No. 11/769,944, wherein a fuel cell is integrated with a shipping bag containing an oxidatively decomposable food and an internal hydrogen source. The fuel cell is operated to convert excess oxygen in the shipping bag to water by reaction with hydrogen.

Thus, the technology to date can generally be characterized as a sealed system that removes or does not remove residual oxygen from within the system by chemical, electrical, or catalytic methods.

Avoiding the functional and economic drawbacks of existing methods would be beneficial for removing oxygen from the storage system. There is also a need in the art to remove residual oxygen from such storage systems.

Disclosure of Invention

In one aspect, the present invention provides shipping bags, packaging modules, systems, and methods useful for extending the shelf life of carbon dioxide-absorbing foods (e.g., fresh fish). One aspect of the present invention provides a pressure stable sealable shipping bag for transporting and/or storing oxidatively degradable foodstuffs having limited oxygen permeability. The shipping bag includes one or more fuel cells contained within the interior of the shipping bag capable of converting hydrogen and oxygen into water. The tote optionally further comprises a holding element adapted to maintain a hydrogen source inside the tote. The hydrogen source holding element in the shipping bag is preferably a box or bladder configured to hold a hydrogen source and in some embodiments a fuel cell. In a preferred embodiment, the shipping bag is selected from the group consisting of a shipping bag comprising a flexible, collapsible, or expandable material that does not tear when collapsed or expanded. In other embodiments, the one or more fuel cells and/or hydrogen source may be located outside the tote. When located outside the shipping bag, the fuel cell is in gaseous communication with the shipping bag.

This aspect of the invention is based on the following findings: carbon dioxide absorbing foods (e.g. fresh fish) can significantly adversely affect the gas composition of the atmosphere above the fish. In such an embodiment, the initially acceptable low level of (for example) oxygen will increase as more and more carbon dioxide is absorbed, resulting in a higher level of oxygen in the remaining gas. This can also cause "vacuuming" situations that can potentially damage the product and shipping bags, causing structural damage or reducing the carbon dioxide concentration below a level effective to inhibit microbial spoilage.

In extreme cases, sufficient carbon dioxide is absorbed such that little or no headspace remains after storage or shipment, creating a harmful vacuum condition.

This aspect of the invention is further based on the discovery that: the above problems are solved by a packaging module for transporting and/or storing carbon dioxide absorbing food, comprising a pressure stable sealed shipping bag having limited oxygen permeability and defining a headspace, wherein the shipping bag is composed of a flexible, collapsible or expandable material that does not crack upon collapse or expansion; an oxidatively decomposable carbon dioxide-absorbing food; a fuel cell for use in combination with a shipping bag capable of converting hydrogen and oxygen into water; a hydrogen source contained, preferably inside the shipping bag, and further wherein the initial headspace comprises at least 30% by volume of the shipping bag and the gas in the headspace comprises at least 99% by volume of a gas other than oxygen. In one embodiment, the headspace comprises at least 50% by volume of the shipping bag. In one embodiment, the headspace comprises about or at least 69% by volume of the shipping bag. In one embodiment, the gas in the headspace comprises at least 60% by volume carbon dioxide. In another embodiment, the gas in the headspace comprises at least 90% by volume carbon dioxide.

In this embodiment, the initial carbon dioxide in the headspace greatly exceeds the amount of carbon dioxide that will be absorbed by the food, thereby providing compensation for its absorption. The amount of carbon dioxide that can be absorbed by the food during storage and/or transportation can be determined empirically or is known in the art.

Another aspect of the invention provides a system useful for transporting and/or storing carbon dioxide-absorbing oxidatively-decomposable foods comprising one or more shipping bags. Each packaging module comprises a pressure-stable, sealed shipping bag having limited oxygen permeability, wherein the shipping bag is comprised of a flexible, collapsible, or expandable material that does not breach upon collapse or expansion; an oxidatively decomposable carbon dioxide-absorbing food; a fuel cell capable of converting hydrogen and oxygen into water; a hydrogen source, and further wherein the initial headspace comprises at least 30 volume% of the shipping bag. In one embodiment, the initial headspace comprises at least 50% by volume of the shipping bag. In another embodiment, the initial headspace comprises about or at least 69% by volume of the shipping bag. In some embodiments, the gas in the headspace comprises at least 99% by volume of a gas other than oxygen. In one embodiment, the gas in the headspace comprises at least 60% by volume carbon dioxide. In another embodiment, the gas in the headspace comprises at least 90% by volume carbon dioxide.

In some embodiments, the fuel cell and/or hydrogen source is located inside the tote. In some embodiments, the packaging module further comprises a holding element adapted to maintain the hydrogen source inside the tote; preferably, the hydrogen source holding element in the tote is configured to hold a cartridge or bladder of the hydrogen source and optionally a fuel cell. In some embodiments, the fuel cell and/or the hydrogen source are located outside the tote. When the fuel cell is located outside the tote, it is in gaseous communication with the tote and one fuel cell can be in gaseous communication with one or more tote and the product of the fuel cell can be located inside or outside the tote.

In some embodiments, the oxidatively decomposable carbon dioxide-absorbing food to be transported and/or stored is preferably fish. More preferably, the fish is fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike. Most preferably, the fresh fish to be transported and/or stored is salmon or tilapia. Freshly cooked perishable food would also be beneficial in a hypoxic environment.

Additionally, in some embodiments, the hydrogen source is a gas-bag hydrogen source, a rigid container hydrogen source, or a gas mixture comprising carbon dioxide and less than 5% hydrogen by volume. In some embodiments, the packaging module further comprises a fan. In some embodiments, the fan is powered by a fuel cell. In some embodiments, the fan is powered by another power source.

In some embodiments, the system further includes a temperature control system that can be located inside or outside the packaging module to maintain the temperature inside the module at a level sufficient to maintain food freshness.

Another aspect of the invention provides a method for transporting and/or storing oxidatively degradable foodstuff using the packaging module set forth above. The method comprises the following steps: removing oxygen from the packaging module containing the oxidatively decomposable carbon dioxide absorbing food to create an oxygen reduced environment within the packaging module; filling a shipping bag with a low oxygen gas to provide an initial gaseous headspace, wherein the initial headspace comprises at least 30 volume percent of the shipping bag and the gas in the headspace comprises at least 99 volume percent of a gas other than oxygen; sealing the shipping bag; operating a fuel cell during transport or storage to convert oxygen in the tote to water by reaction with hydrogen so as to maintain a reduced oxygen environment within the tote; and transporting or storing the material in the shipping bag. The packaging module comprises a pressure-stable sealable shipping bag having limited oxygen permeability, wherein the shipping bag is comprised of a flexible, collapsible, or expandable material that does not rupture when collapsed or expanded; a fuel cell and a source of hydrogen. In one embodiment, the gas in the headspace comprises at least 60% by volume carbon dioxide. In another embodiment, the gas in the headspace comprises at least 90% by volume carbon dioxide.

In one embodiment, the oxygen removal process is performed prior to adding food to the shipping bag; in another embodiment, after food is added to the shipping bag. In some embodiments, the shipping bag includes plumbing valves and fittings inside the shipping bag for flushing the shipping bag with a hypoxic gas source to fill the headspace. In some embodiments, the shipping bag is flushed and the fuel cell is then turned on. The fuel cell then continues to remove residual oxygen.

The method may be used to transport or store food for a period of up to 100 days. For example, the storage period is between 5 days and 50 days, or between 5 days and 45 days, or between 15 days and 45 days. In some embodiments, the method further comprises maintaining a temperature in the shipping bag sufficient to maintain freshness of materials during transport or storage.

In a preferred embodiment, the method is carried out such that the reduced oxygen environment comprises less than 1% oxygen, or the reduced oxygen environment comprises less than 0.1% oxygen, or the reduced oxygen environment comprises less than 0.01% oxygen.

The reduced oxygen environment comprises carbon dioxide and hydrogen; comprising carbon dioxide and nitrogen; containing nitrogen; or contain carbon dioxide, nitrogen and hydrogen.

Yet another aspect of the present invention provides a method of removing oxygen from the interior of a shipping bag containing oxidatively decomposable food without the use of any chemical, electrical and/or catalytic methods.

In particular, this aspect of the invention is based on the following findings: a properly configured shipping bag will allow the shipping bag to be flushed with a source of hypoxic gas so as to flush out of the shipping bag before any oxygen that accumulates in the shipping bag reaches a concentration level that adversely affects food. Accordingly, in one aspect of the method, there is provided a method of removing oxygen from a shipping bag having oxidatively degradable foodstuff, the method comprising:

a) a shipping bag having a sealable gas inlet port and a sealable gas outlet port, both ports located in a headspace of the shipping bag, wherein the shipping bag comprises a flexible, collapsible, or expandable material that does not breach upon collapse or expansion;

b) adding oxidatively degradable foodstuff to the shipping bag in an amount that does not block the inlet and outlet ports;

c) sealing the shipping bag;

d) injecting a sufficient source of hypoxic gas into a tote through an inlet port while venting gas through an outlet port, in such a way as to effect one or more initial flushes of the tote with the gas source to provide a hypoxic atmosphere and a gas headspace with sufficient volume in the tote to allow gas to be absorbed into the food without increasing the oxygen content in the remaining gas headspace in the tote to a level above about 1500 ppm;

e) sealing the inlet and outlet ports; and

f) optionally periodically flushing the shipping bag with a source of hypoxic gas so as to maintain sufficient gas headspace after flushing to compensate for gas absorbed into the food so that the oxygen concentration in the remaining gas headspace does not exceed 1500ppm at any given time.

In a preferred embodiment, the shipping bag does not contain any internal components to remove oxygen from the shipping bag, such as fuel cells, catalysts, and the like.

The oxidatively degradable foodstuff to be transported and/or stored is preferably fish. More preferably, the fish is fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike. Most preferably, the fresh fish to be transported and/or stored is salmon or tilapia.

The vertical configuration of the shipping bag disclosed herein facilitates minimizing horizontal space requirements to ship the maximum number of trays side-by-side. Embodiments with horizontal expansion of the headspace may not be economically viable on a large scale and furthermore, as long as the headspace is kept at a positive pressure, it is not leak resistant. In certain embodiments, the shipping bag expands no more than about 20% in the horizontal direction, with the remaining gas expansion being in the vertical direction, thereby resulting in a "head pressure" and head space height of the shipping bag. The shipping bag is configured to expand in a vertical manner, causing an initial "top pressure". The initial shipping bag top pressure can range from about 0.1 inches to about 1.0 inches of water or more above atmospheric pressure. The flexible carrier bag can be made more flexible in the vertical direction than in the horizontal direction by conventional methods, such as using a more flexible material in the vertical direction.

Additionally, in some embodiments, the hypoxic gas source is any external gas source that can be adapted to provide a gas source to the inlet port of the shipping bag. Preferably, the gas source is carbon dioxide and, more preferably, the carbon dioxide contains less than about 1500ppm oxygen. Even more preferably, the carbon dioxide to be injected into the shipping bag contains less than about 100ppm oxygen.

In some embodiments, the shipping bag further comprises a temperature control system external to the packaging module to maintain the temperature inside the module at a level sufficient to maintain food freshness.

Another aspect of the invention provides a method for transporting and/or storing oxidatively degradable foodstuff within a shipping bag as set forth above. The method comprises the following steps: flushing oxygen from a shipping bag with carbon dioxide containing less than 1500ppm oxygen, wherein the shipping bag contains oxidatively decomposable food, thereby creating an oxygen-reduced environment within the shipping bag; sealing the shipping bag; and optionally periodically flushing the shipping bag with carbon dioxide to maintain a reduced oxygen environment within the shipping bag; and transporting and/or storing food in the shipping bag, wherein the shipping bag comprises a flexible, collapsible, or expandable material that does not breach upon collapse or expansion.

In one embodiment, the oxygen removal process is performed prior to adding the food to the shipping bag; in addition toIn one embodiment, this is done after the food is added to the shipping bag. In one embodiment, oxygen removal may be accomplished by gas scouring through inlet and outlet ports, which are preferably installed in the headspace of the shipping bag. In some embodiments, multiple periodic gas flushes can be implemented. The inlet and outlet ports are sealable to isolate the interior of the shipping bag after flushing the bag with the hypoxic gas source. In one embodiment, the inlet and outlet ports are holes, wherein the holes can simply be covered and uncovered when a gas flush is required. In such an embodiment, the apertures (inlet and outlet ports) may be covered with adhesive tape. This allows the inlet and outlet ports to be periodically sealed and unsealed. This configuration facilitates multiple gas flushes over time to remove oxygen and increase low oxygen gases (e.g., nitrogen and/or CO)₂) Horizontal economic practice.

The method may be used to transport and/or store food for a period of up to 100 days. In certain embodiments, the methods may be used to transport and/or store food for a period of time exceeding 100 days. For example, the storage period is between 5 days and 50 days, or between 15 days and 45 days. In some embodiments, the method further comprises maintaining a temperature in the shipping bag sufficient to maintain freshness of the material during transport or storage.

In a preferred embodiment, the method is carried out such that the reduced oxygen environment comprises less than 2% oxygen, or the reduced oxygen environment comprises less than 1.5% oxygen, or the reduced oxygen environment comprises less than 1% oxygen, or the reduced oxygen environment comprises less than 0.1% oxygen, or the reduced oxygen environment comprises less than 0.01% oxygen. The level of oxygen can be monitored.

The reduced oxygen environment comprises carbon dioxide, or in some cases carbon dioxide and nitrogen.

Drawings

The invention will be further elucidated with reference to the drawing.

Fig. 1 is a schematic view of a packaging module for transporting or storing an oxidatively decomposable material.

Fig. 2 is a schematic diagram of a system including a plurality of packaging modules in a container.

Fig. 3 is a schematic diagram of an embodiment of a fuel cell with an oxygen scavenger.

Fig. 4 is a graph showing the increase in duration of low oxygen levels using the packaging module compared to a standard MAP system.

Figure 5 is a photograph of fresh salmon grown in the Atlantic Chilean (Chilean Atlantic) stored in a packaging module compared to a standard MAP storage system.

Fig. 6 is a schematic diagram of an embodiment of a fuel cell having an oxygen remover with a carbon dioxide remover.

FIG. 7 is a photograph of an embodiment of a packaging module prior to shipping.

FIG. 8 is a photograph of an embodiment of a packaging module after shipping.

Fig. 9 shows an exemplary shipping bag.

Fig. 10 is a schematic view of a shipping bag for transporting or storing an oxidatively-decomposable material.

Fig. 11 is a schematic diagram of a system including a plurality of shipping bags in a vehicle connected to a hypoxic gas source.

Fig. 12 is a photograph of a shipping bag with an oxidizable decomposition material carried in a transport.

Detailed Description

The present invention encompasses systems and methods useful for transporting and storing oxidatively degradable foodstuffs. The systems and methods described herein allow for periodic or continuous removal of oxygen from the atmospheric environment surrounding the oxidatively degradable foodstuffs stored in individual shipping bags, for example, within a shipping container. In some embodiments, the food is an oxidatively decomposable food that absorbs carbon dioxide.

As described more fully below, the shipping bag or packaging module used in the present invention preferably does not incorporate an integrated temperature control system, but rather relies on the temperature control system of the shipping container from which it is shipped. In addition, the shipping bag or packaging module is designed to withstand or compensate for internal pressure losses (or gains) caused, for example, by food absorption of non-oxygen (carbon dioxide) gases during shipping and/or transport by, for example: a flexible, collapsible or expandable material is employed that does not breach upon collapse or expansion and further employs a gaseous headspace within the shipping bag to compensate for the absorption without creating vacuum conditions and/or not allowing the oxygen content of the gas in the shipping bag to exceed 1500 ppm.

Periodic or continuous removal of oxygen during transport and/or storage allows for a controlled oxygen-reduced environment suitable for maintaining freshness of the material over a long period of time. Accordingly, the oxidatively-decomposable material can be transported and/or stored for a longer period of time than is currently possible using conventional shipping and storage techniques. The systems and methods set forth herein allow for the transportation of oxidatively degradable materials (e.g., carbon dioxide absorbing oxidatively degradable foodstuffs such as fish), for example, using transportation vehicles to markets that can typically only be served by more expensive aerial transportation.

In one embodiment, the present invention provides a system and method for extending the storage life of oxidatively degradable foodstuffs. In a preferred embodiment, the oxidatively degradable foodstuff is non-respirable. Non-absorbent foods do not breathe. That is, these foods do not inhale oxygen, with concomitant release of carbon dioxide. Examples of non-respiratory foods include fresh or treated fish, meats (e.g., beef, pork, and lamb), poultry (e.g., chicken, turkey, and other wild and poultry), and baked goods (e.g., bread, tortillas, and pastries, packaged mixes for producing bread and pastries, and grain-based snack foods). Preferred non-respiratory foods to be transported and/or stored by the present systems and methods include fresh or treated fish, such as salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, pollack, walleye, halibut, atlantic cod, redspot salmon, shellfish, and other seafood. More preferably, the non-respiratory food is fresh salmon or fresh tilapia, and most preferably, the non-respiratory food is fresh salmon cultivated in the atlantic chile.

In general, the systems and methods of the present invention relate to a tote, oxidatively decomposable food to be transported and/or stored, and a hypoxic gas source that periodically flushes the tote with a hypoxic gas (e.g., carbon dioxide) to remove any available oxygen from inside the tote so as to control the gas environment around the food during at least a portion of the storage and/or transport. In a preferred embodiment, the reduced oxygen environment within the shipping bag is created by: applying a vacuum through the inlet port and/or introducing a source of hypoxic gas flushes the environment inside the tote while venting gases present inside the tote through the outlet port. After the tote is flushed, the inlet and outlet ports are sealed and the environment within the tote is a reduced oxygen environment. Optionally, when oxygen is present, the shipping bags are then flushed periodically with carbon dioxide, as needed, throughout the duration of transport and/or storage, to maintain an oxygen-reducing environment within the packaging module, thereby maintaining freshness of the oxidatively-decomposable material. In certain embodiments, an oxygen sensor is present inside the shipping bag to signal the need for a carbon dioxide flush.

In some embodiments, the systems and methods of the present invention relate to a packaging module comprising: a shipping bag for transporting and/or storing carbon dioxide absorbing oxidatively decomposable food; and means for continuously removing any available oxygen from the interior of the pouch when oxygen is present, so as to control the gaseous environment surrounding the food during at least a portion of storage and/or transport. This device is also called a deaerator. In some cases, it will be desirable to employ more than one oxygen scavenger to more effectively remove oxygen from the shipping bag environment. The carbon dioxide absorbing oxidatively decomposable food is inserted into the shipping bag and the environment within the shipping bag is manipulated to create an oxygen reduced environment within the shipping bag. In a preferred embodiment, the reduced oxygen environment within the pouch is created by applying a vacuum and/or introducing a source of hypoxic gas to flush the environment within the pouch. After the pouch is flushed, the environment within the pouch is a reduced oxygen environment. The shipping bag is filled with a low oxygen gas to provide a gas headspace such that the volume of the gas headspace is greater than the volume of gas absorbed by the oxidatively decomposable food that absorbs carbon dioxide. In one embodiment, the shipping bag is filled with carbon dioxide such that the gas headspace comprises at least 30 volume percent of the total volume of the shipping bag and the gas in the headspace comprises at least 99 volume percent carbon dioxide. The pouches are then sealed. When oxygen is present, the oxygen scavenger is operated throughout the duration of transport and/or storage to maintain an oxygen reducing environment within the packaging module, thereby maintaining freshness of the oxidatively decomposable material that absorbs carbon dioxide. However, when the amount of carbon dioxide used is significantly greater than the amount to be absorbed by the food, i.e., limiting the amount of oxygen in the headspace in volume%, the shipping bag may collapse if the gaseous headspace is insufficient to compensate for the absorption of carbon dioxide.

The term "reduced oxygen gas source" refers to a gas source containing less than 1000ppm oxygen, preferably less than 100ppm oxygen, and more preferably less than 10ppm oxygen. The hypoxic gas source preferably comprises CO₂Or containing CO₂A gas mixture as one of its components. CO 2₂Colorless, odorless, nonflammable and bacteriostatic, and it does not leave toxic residues on food products. In one embodiment, the hypoxic gas source is 100% CO₂. In another embodiment, the hypoxic gas source is CO₂With nitrogen or another inert gas. Examples of inert gases include, but are not limited to, argon, krypton, helium, nitric oxide, nitrous oxide, and xenon. The composition of the hypoxic gas source can be varied to suit the food, and is well known in the art. For example, a hypoxic gas source for transporting and storing salmon is preferably 100% CO₂. Other fish such as tilapia preferably use 60% CO₂And 40% nitrogen as a source of hypoxic gas for storage or transport.

As set forth above, a pressure stable sealable tote having limited oxygen permeability is a tote comprising a flexible, collapsible, or expandable material that does not breach upon collapse or expansion, or a tote comprising a rigid material. Typically, shipping bags are constructed from flexible cast or extruded plastic sheets.

Flexible, collapsible or expandable pouch materials for use in the present invention are those having limited oxygen permeability. The material having limited oxygen permeability preferably has an Oxygen Transport Rate (OTR) of less than 10 cubic centimeters per 100 square inches per 24 hours per atmosphere, a more preferred material having limited oxygen permeability is a material having an OTR of less than 5 cubic centimeters per 100 square inches per 24 hours per atmosphere, an even more preferred material having limited oxygen permeability is a material having an OTR of less than 2 cubic centimeters per 100 square inches per 24 hours per atmosphere, and a most preferred material having limited oxygen permeability is a material having an OTR of less than 1 cubic centimeter per 100 square inches per 24 hours per atmosphere. A non-exhaustive list of materials that can be used to make flexible, collapsible, or expandable shipping bags is shown in table 1.

TABLE 1

The tote can further include one or more sources of hypoxic gas external to the tote and in gaseous contact with the tote through the inlet port to periodically flush the tote, thereby removing any oxygen from the environment within the tote through the one or more outlet ports. During use of the shipping bag, oxygen may accumulate in the shipping bag, for example, by diffusing through the shipping bag or at the shipping bag seal, through materials having limited oxygen permeability. Containers within the shipping bag that can oxidize and decompose the food or package the food can also release oxygen. In a preferred embodiment, the carbon dioxide is carbon dioxide gas having less than 10ppm oxygen.

In some embodiments, the shipping bag further comprises one or more oxygen scavengers to continuously remove oxygen from the environment within the shipping bag as long as oxygen is present. The oxygen scavenger maintains the reduced oxygen environment within the shipping bag by continuously removing oxygen that may be introduced into the system after the bag is sealed. For example, oxygen may be introduced as a result of diffusion through the shipping bag or at the shipping bag seal by a material having limited oxygen permeability. The carbon dioxide absorbing oxidatively decomposable food or the container packaging the food within the shipping bag may also release oxygen.

In a preferred embodiment, the oxygen remover is a fuel cell that consumes molecular oxygen. Preferably, the fuel cell is a hydrogen fuel cell. As used herein, a "hydrogen fuel cell" is any device capable of converting oxygen and hydrogen into water. In a preferred embodiment, the entire fuel cell is located inside the shipping bag. This may be achieved by having a source of hydrogen either internal or external to the tote or packaging module. The anode of the fuel cell is in communication with a hydrogen source. The hydrogen source produces protons and electrons. The cathode of the fuel cell is in communication with the environment (oxygen source) in the shipping bag. In the presence of oxygen, protons and electrons produced at the anode interact with oxygen present at the cathode to produce water. In a preferred embodiment, the fuel cell does not require the use of an external power source to convert oxygen and hydrogen into water. In yet another embodiment, the fuel cell is connected to an indicator that indicates when the fuel cell is operating and when hydrogen is available.

In another embodiment, the physical fuel cell is external to the shipping bag, but in direct communication with the gas environment of the shipping bag in a manner such that the products produced at the anode and cathode are maintained inside the shipping bag. One fuel cell may be in gaseous communication with one or more shipping bags. In this embodiment, the fuel cell is considered to be inside the tote because its products remain inside the tote. When the fuel cell is physically located outside the shipping bag, water produced by the fuel cell may be released outside the shipping bag.

In a preferred embodiment, the hydrogen source is pure hydrogen. The hydrogen source is preferably housed within the bladder and the bladder is housed inside the tote bag so that the entire process is housed within the tote bag. The hydrogen source is preferably in direct communication with the anode of the hydrogen fuel cell in a manner that provides hydrogen during the duration of the transport or storage period. The bladder is made of any material capable of containing hydrogen. For example, the materials listed in table 1 may be used as the airbag material.

In a preferred embodiment, the balloon contains an uncompressed hydrogen source, but a compressed hydrogen source can be used, so long as the balloon can contain a compressed source therein.

In another embodiment, the hydrogen source is contained within a rigid container (e.g., a gas cylinder) that is contained within a tote bag, such that the entire process is performed within the tote bag. In this embodiment, the hydrogen source is a compressed or uncompressed hydrogen source. The rigid container is in direct communication with the hydrogen fuel cell in a manner that provides hydrogen for the duration of the transport or storage period. The compressed hydrogen source is preferably maintained at a pressure of no greater than 10,000 psia. Preferably, the hydrogen source is uncompressed, for example, having a pressure of no greater than 40 psia.

In other embodiments, the hydrogen source is produced by a chemical reaction. Examples of chemical hydrogen generation processes are well known in the art and include hydrogen generation by electrolytic processes, including processes using PEM electrolyzers, alkaline electrolyzers using sodium or potassium hydroxide, solid oxide electrolyzers, and processes generating hydrogen from sodium borohydride. In each case, the hydrogen produced makes available to the anode of the fuel cell.

In another embodiment, the hydrogen source is a gas mixture comprising hydrogen present in the environment of the tote. In this embodiment, the gas mixture preferably comprises carbon dioxide and hydrogen. In other embodiments, the gas mixture comprises nitrogen and hydrogen. In other embodiments, the gas mixture comprises hydrogen, carbon dioxide, and nitrogen. It is contemplated that other inert gases may be present in the gas mixture. The amount of hydrogen present in the gas mixture is preferably less than 10% by volume hydrogen, more preferably less than 5% by volume hydrogen, most preferably less than 2% by volume hydrogen. This gas mixture is introduced into the shipping bag before, during or after the introduction of the oxidatively decomposable material and before sealing the shipping bag.

In some embodiments, a fuel cell includes a carbon dioxide remover in direct communication with a sealed anode assembly of the fuel cell. Carbon dioxide may permeate through the PEM to the anode, interfering with the passage of hydrogen to the anode plate. Removing some or all of the carbon dioxide from the anode plate of the fuel cell by the carbon dioxide remover may increase the hydrogen reaching the fuel cell and thereby increase the ability of the fuel cell to remove oxygen from the shipping bag environment.

Many processes are known in the art that can use a carbon dioxide remover. These include absorption processes, adsorption processes (e.g., pressure-swing adsorption (PSA) and Thermal Swing Adsorption (TSA) processes), and membrane-based carbon dioxide removal. Compounds that can be used in the carbon dioxide remover include, but are not limited to, slaked lime, activated carbon, lithium hydroxide, and metal oxides (e.g., silver oxide, magnesium oxide, and zinc oxide). Carbon dioxide may also be removed from the anode by purging the anode with a gas (e.g., hydrogen or water vapor).

In one embodiment, the carbon dioxide remover comprises slaked lime. In this embodiment, for example, the slaked lime is contained in a cartridge that is in vapor communication with the fuel cell anode such that carbon dioxide present at the anode plate of the fuel cell contacts and is absorbed into the slaked lime. Particular embodiments include two slaked lime cartridges, each in communication with the anode outlet vapor. The slaked lime filter facilitates the removal of carbon dioxide from the anode plate of the fuel cell (fig. 6).

The shipping bag may be configured to provide access to tubing, lines, etc. so that an external gas, such as carbon dioxide, may be introduced through the inlet port. The inlet port is provided using a fitment that is sealable and can maintain a hypoxic environment within the pouch. In some embodiments, an external power source may be used to operate the fan and deaerator. In one particular embodiment, the shipping bag is configured to allow hydrogen from an external source to be introduced into an internal fuel cell hydrogen supply system. In yet another embodiment, the external hydrogen source is intended to assist in purging the fuel cell with hydrogen.

Oxygen scavengers other than hydrogen fuel cells may be used to remove oxygen from the shipping bag. For example, an oxygen absorber such as an iron-containing absorbent and an oxygen adsorbent may be used. Oxygen absorbers and adsorbents are known in the art and are commercially available. Deaerators also include deaerators that utilize Pressure Swing Adsorption (PSA) processes and membrane separation processes.

Catalytic systems, such as those utilizing elemental metals such as platinum or palladium catalysts, may be used as oxygen scavengers, but the use of powders required to provide high catalytic surface areas presents a contamination risk. However, these catalytic systems can also be used when appropriate precautions are taken. The safeguards include embedding the metal catalyst within a membrane electrode assembly, such as a membrane electrode assembly found in a PEM fuel cell.

The tote preferably further comprises a holding element adapted to maintain the hydrogen source so as to stably hold the hydrogen source within the tote. In a preferred embodiment, the holding element is a cartridge configured to stably hold the hydrogen source. In a further preferred embodiment, the holding element is configured to hold both the hydrogen source and the fuel cell. In other embodiments, the retaining element is a sleeve secured to the inner wall of the shipping bag. The sleeve is capable of holding a gas-containing hydrogen source or a rigid container hydrogen source and other containers suitable for holding the hydrogen source. In either case, the hydrogen source is in direct communication with the anode of the fuel cell.

When the oxygen scavenger used in the packaging module is a hydrogen fuel cell, then there will be a certain amount of water in liquid or gaseous form due to the reaction of hydrogen with oxygen. In some embodiments, the water produced thereby is released into the shipping bag. It may be desirable to include a means for containing or removing water within the shipping bag. For example, the shipping bag may further include a water holding apparatus, such as a tray or water tank, configured to collect water as it is produced at the fuel cell. Alternatively, the shipping bag may contain a desiccant or absorbent material for absorbing and containing water. Suitable desiccant and absorbent materials are well known in the art. Alternatively, the water may be discharged outside the shipping bag, thereby providing a suitable environment for storage and transportation of the goods optimally stored in a dry environment.

The shipping bag is configured to maintain an oxygen-reduced environment around the material. The reduced oxygen environment allows for the storage and/or transport of materials for long periods of time while maintaining the freshness of the materials. After introducing the material but before sealing the tote, the environment within the tote is optionally flushed by applying a vacuum and/or introducing a source of low oxygen free gas. At this time, the environment inside the shipping bag is a reduced oxygen environment. In particular embodiments, the oxygen level in the reduced oxygen environment is less than 1% oxygen, or the oxygen level in the reduced oxygen environment is less than 0.1% oxygen, or the oxygen level in the reduced oxygen environment is less than 0.01% oxygen.

After a period of time, the oxygen level present in the shipping bag or packaging module is still at a reduced level because the exchange of gas between the food and the shipping bag environment is naturally minimized or stopped. At this time, the fuel cell will stop operating. In one embodiment, the fuel cell may be programmed to cease operation after an initial period of time sufficient to naturally minimize or cease gas exchange. Preferably, the fuel cell may be programmed to cease operation after a period of between about 0.5 hours and 50 hours; more preferably, the fuel cell may be programmed to cease operation after a period of between about 1 hour and 25 hours; more preferably, the fuel cell may be programmed to cease operation after a period of between about 2 hours and 15 hours; even more preferably, the fuel cell may be programmed to cease operation after a period of between about 3 hours and 10 hours.

In some embodiments, the source of hypoxic gas is introduced into the shipping bag prior to sealing the shipping bag. The hypoxic gas source preferably comprises CO₂Or containing CO₂A gas mixture as one of its components. CO 2₂Colorless, odorless, nonflammable and bacteriostatic, and it does not leave toxic residues on food products. In one embodiment, the hypoxic gas source is 100% CO₂. In another embodiment, the hypoxic gas source is CO₂With nitrogen or another inert gas. Examples of inert gases include, but are not limited to, argon, krypton, helium, nitric oxide, nitrous oxide, and xenon. The composition of the hypoxic gas source can be varied to suit the food, and is well known in the art. For example, a hypoxic gas source for transporting and storing salmon is preferably 100% CO₂. Other fish such as tilapia preferably use 60% CO₂And 40% nitrogen as a source of hypoxic gas for storage or transport.

To compensate for pressure differentials created during long term transport or storage, the shipping bag contains an initial headspace volume to allow for the absorption of gases (e.g., oxygen), a low oxygen gas source (e.g., carbon dioxide). The term "initial headspace" means the amount of excess gas volume of the shipping bag after it has been filled with the oxidatively degradable food that absorbs carbon dioxide. In some embodiments, the initial headspace comprises from about 30% to about 95% of the volume of the interior of the shipping bag. In other embodiments, the initial headspace comprises from about 35% to about 40% of the internal volume of the shipping bag, or the initial headspace comprises from about 30% to about 35% of the internal volume of the shipping bag, or the initial headspace comprises about 35% of the internal volume of the shipping bag.

Finally, the shipping bag is filled with a sufficient amount of low oxygen gas to provide an initial gas headspace such that the volume of the gas headspace is greater than the volume of gas absorbed by the oxidatively decomposable food, thereby compensating for the pressure differential created during long term transportation or storage. The result of the pressure difference can be seen in fig. 7 and 8. Figure 7 shows the flexible shipping bag of the present invention that has been filled with sufficient carbon dioxide to accommodate the absorption of carbon dioxide by food throughout the shipping and handling cycle of the shipping bag and to prevent negative pressure from the oxygen removal process. Fig. 8 shows the same shipping bag of fig. 7 after 17 days of transport with a reduced amount of gas headspace. Although the photograph of fig. 8 shows that it appears that the right side shipping bag expands more (or contracts less) than the left side shipping bag, in practice the two shipping bags contract equally when viewed from all sides. The amount of headspace remaining after transport should be sufficient so that a negative pressure is not created, as this "vacuum" can potentially damage the product, reduce the carbon dioxide concentration below a level effective to inhibit microbial spoilage, and/or increase the residual oxygen concentration and increase the likelihood of leakage. In certain embodiments, the concentration of carbon dioxide in the shipping bag after transport or storage is at least 90%.

The shipping bag is configured to communicate the interior shipping bag environment with an oxygen scavenger so as to allow for continuous removal of molecular oxygen from the interior shipping bag environment as long as oxygen is present in the shipping bag environment. An oxygen scavenger in the shipping bag is configured to remove oxygen from the internal shipping bag environment in order to maintain oxygen levels below a level that would cause a reduction in freshness or spoilage of the material. This reduced oxygen level is maintained during transport and/or storage by the oxygen scavenger. Oxygen in the reduced oxygen environment is at a level of less than 1% oxygen, more preferably less than 0.1% oxygen, and most preferably less than 0.01% oxygen.

The efficiency of the deaerator may be enhanced by using a fan to circulate air within the shipping bag, thereby promoting contact of the deaerator with oxygen in the environment of the shipping bag. In certain embodiments, when a fuel cell is used, the fan may be configured to run on the energy generated when the fuel cell converts hydrogen and oxygen into water.

In the event that the integrity of the shipping bag is compromised and a large volume of oxygen-containing air is accidentally introduced into the shipping bag environment, the oxygen scavenger will not be able to remove all of the introduced oxygen. In a preferred embodiment, the shipping bag further contains an oxygen indicator that will alert the shipping bag to the fact that the oxygen level has exceeded a level set forth as a reduced oxygen environment.

In some embodiments, it is expected that multiple flushes with hypoxic gas will allow the food to absorb the gas, thereby alleviating the need for a larger initial headspace. However, it is also expected that headspace may be required in large scale shipping (i.e., 2,000 pounds of food packaged in multiple cartons), which is impractical for shipping purposes because the number of days required for gas absorption is too large.

In certain embodiments, the shipping bag is capable of accommodating extremely large head spaces (primarily accommodating CO)₂Absorb and protect against/delay air leakage) so that the combination of headspace and multiple initial gas flushes will not require continuous oxygen monitoring or further periodic gas flushes in addition to the initial multiple gas flushes. It is contemplated that the initial gas flush may be performed periodically during the first 72 hours of the shipping bag being sealed and containing the oxidatively degradable foodstuff. Alternatively, the initial gas flush may be performed during the first 72 hours or less of sealing the shipping bag, or the first 60 hours, or the first 48 hours, or the first 24 hours.

The vertical configuration of the shipping bag disclosed herein facilitates minimizing horizontal space requirements to ship the maximum number of trays side-by-side. Embodiments with horizontal expansion of the headspace may not be economically viable on a large scale and furthermore, as long as the headspace is kept at a positive pressure, it is not leak resistant. In certain embodiments, the inflation of the shipping bag in the horizontal direction is no more than about 20%, with the remaining gas inflation being in the vertical direction, thereby resulting in a "head pressure" and head space height of the shipping bag. The shipping bag is configured to expand in a vertical manner, causing an initial "top pressure". The initial shipping bag top pressure can range from about 0.1 inches to about 1.0 inches of water or more above atmospheric pressure.

In certain embodiments, the hypoxic gas source is programmed to flush the internal environment of the shipping bag at predetermined intervals throughout the duration of transportation and/or storage. In other embodiments, the hypoxic gas source is programmed to flush the internal environment of the shipping bag when the oxygen level of the internal shipping bag environment exceeds a level that is harmful to food. At the beginning of transport and/or storage, oxygen may be released from the oxidatively decomposable food within the shipping bag or from the container in which the food is packaged.

In a preferred embodiment, the shipping bag further includes an indicator that will alert the fact that the oxygen level in the shipping bag has exceeded a level set forth as a reduced oxygen environment. In certain embodiments, the hypoxic gas source is programmed to flush the internal environment of the shipping bag when the oxygen level in the reduced oxygen environment is about 2% oxygen, more preferably about 1.5%, more preferably about 1%, more preferably about 0.1%, most preferably about 0.01% oxygen, or when the oxygen level exceeds about 1500ppm oxygen. In a particular embodiment, an oxygen sensor, such as a trace oxygen sensor (Teledyne), is used to monitor the level of oxygen present in the shipping bag environment.

The shipping bag optionally contains monitors to monitor oxygen levels, hydrogen levels, fuel cell operation and temperature. In a particular embodiment, an oxygen sensor, such as a trace oxygen sensor (terlidan corporation), is used to monitor the level of oxygen present in the shipping bag environment.

In some embodiments, the shipping bag comprises a cartridge (see fig. 9) containing a device comprising a fuel cell; an oxygen indicator that alerts when the oxygen level in the shipping bag exceeds a level set forth as a reduced oxygen environment; and/or monitors to monitor oxygen levels, hydrogen levels, fuel cell operation, and temperature. The cassette further optionally includes a visual indicator (e.g., an LED light) that indicates a problem with the device in the cassette so that the problematic device or cassette can be replaced immediately prior to sealing the shipping bag. This facilitates rapid detection of any fault caused by unskilled personnel and allows the cassette to be quickly returned for servicing with minimal testing. The cartridge also preferably alerts the user when the system arrives, if oxygen or temperature (time and temperature) exceed limits, using wireless communication (e.g., radio frequency transmission) and visual indicators (e.g., red LED lights).

Another aspect of the invention provides a packaging module that can be used to transport and/or store an oxidatively-decomposable material. The packaging module comprises a shipping bag configured as described above. In the packaging module, the shipping bag is sealed and contains carbon dioxide absorbing oxidatively-decomposable material to be transported and/or stored and a device that removes oxygen from the ambient environment of the material so long as oxygen is present. The device is located within a sealed shipping bag. Temperature control means such as air conditioning, heating and the like are preferably not integrated into the packaging module, and the module is sized so that a freight container containing a single temperature control means may contain a plurality of modules. In such a case, each shipping bag may be made to have a different gas environment and a different packaging material.

Another aspect of the invention provides a system for transporting and/or storing carbon dioxide absorbing oxidatively-degradable foodstuffs. The system includes one or more packaging modules, each packaging module including a shipping bag, an oxidatively decomposable food that absorbs carbon dioxide, and a deaerator. The packaging module and its components are as set forth above.

The system or shipping bag is configured to be suitable for transport or storage in a vehicle. By vehicle is meant any container that can be used to transport and/or store the system, including, but not limited to, marine vehicles, truck vehicles (e.g., tractor-trailers), railroad cars, and aircraft capable of transporting cargo loads. In some embodiments, the shipping bag further comprises means for monitoring and/or recording the temperature of the system or container. Devices are commercially available from manufacturers including Xinde corporation (Sensitiech), Temple, Rogtaige corporation (Logitag), Dickson corporation (Dickson), Marathon corporation (Marathon), Deutsche corporation (Testo), and Hobo.

As noted above, one or more totes or packaging modules may be used in a single conveyance, and thus, each packaging module may be configured to have a different gas environment and different food. Furthermore, opening the conveyance does not disrupt the internal atmosphere of any one tote or packaging module at the time of delivery, and thus, one or more totes or packaging modules may be delivered at one location and the other totes or packaging modules at a different location. The size of each shipping bag or packaging module may be configured prior to shipment to conform to the amount of food desired by each buyer. Thus, the shipping bags or packaging modules may preferably be sized to hold as little as several ounces of food to as much as or greater than 50,000 pounds or 1 ton of food. In addition, the vertical configuration facilitates minimizing horizontal space requirements to transport the maximum number of trays side-by-side. Embodiments with horizontal expansion of the headspace may not be economically viable on a large scale and furthermore, as long as the headspace is kept at a positive pressure, it is not leak resistant. The number of packing modules in each system depends on both the size of the vehicle used to transport and/or store the system and the size of the packing modules. Specific examples of the number of packaging modules in each system are set forth in the description of specific embodiments below.

Each packaging module may be sized large enough to package a load of about 500 pounds or more of the carbon dioxide absorbing oxidatively decomposable food into a single shipping bag. In some embodiments, about 500 pounds, or about 1000 pounds, or about 2000 pounds, or more than about 2000 pounds of the carbon dioxide absorbing oxidatively decomposable food can be packaged into a single shipping bag. This larger size allows the vehicle to be filled to full load without the need to stack the totes, thereby allowing a gas headspace to exist. If the packaging modules are smaller than the inside dimensions of the conveyance, scaffolding can be employed to hold the packaging modules and allow stacking.

In another embodiment, the system comprises one or more shipping bags, each containing an oxidatively decomposable food that absorbs carbon dioxide. In this embodiment, the shipping bag is removably attached to a separate module containing an oxygen scavenger. When the oxygen scavenger is a hydrogen fuel cell, the individual modules also contain a source of hydrogen. The deaerator is used to remove oxygen from all shipping bags connected to the individual modules. In this embodiment, the physical fuel cell is located outside the shipping bag, but in direct communication with the gas environment of the shipping bag. In some embodiments, the products produced at the anode and cathode are maintained inside the shipping bag. In this embodiment, the fuel cell is considered to be inside the shipping bag because its products are maintained inside the shipping bag. In another embodiment, water produced by the fuel cell is released outside the shipping bag. In another embodiment, the shipping bag is a rigid shipping bag and the separate modules further contain a source of gas to maintain positive pressure in the connected shipping bag. The container optionally contains monitors to monitor the oxygen level, hydrogen level and temperature within the bag; and an indicator to indicate operation of the fuel cell. In one embodiment, the module is a box that is sized to be similar to the packaging module. In another embodiment, the module is secured to a wall, lid or door of a conveyance for a transport and/or storage system.

In some embodiments, the system and/or conveyance further comprises a cooling system for maintaining the packaging module at a temperature sufficient to maintain freshness of the carbon dioxide-absorbing oxidatively-decomposable food. The temperature required to maintain the freshness of the oxidatively decomposable food that absorbs carbon dioxide depends on the nature of the food. Those skilled in the art will know of, or be able to determine, the appropriate temperature required for the material being transported or stored in the system or conveyance. For the transport and/or storage of food, the temperature will typically be about 30 ° F (degrees fahrenheit). The temperature is typically maintained in the range of 32 ° F to 38 ° F, more preferably in the range of 32 ° F to 35 ° F, and most preferably in the range of 32 ° F to 33 ° F or 28 ° F to 32 ° F. For example, a suitable temperature for preserving fish during transportation or storage is between 32 ° F and 35 ° F. The temperature is allowed to vary as long as the temperature is maintained within a range in which food is preserved. In some embodiments, the shipping bag further comprises means for monitoring and/or recording the temperature of the system or container. Devices are commercially available from manufacturers including Xinde, Teplerian, Rogotigger, Dickson, Marathon, Deutsche, and Hobo.

In one embodiment, the system is capable of maintaining the packaging module at a food preservation and refrigeration temperature. Alternatively, the transport for the transport and/or storage system is a refrigerated transport capable of maintaining the packaging module at a food holding refrigeration temperature.

It is expected that it may be desirable to limit the exposure of food to excess hydrogen during transport or storage. Thus, in some embodiments, the shipping bag or system is configured to minimize exposure of the food to hydrogen present in the shipping bag environment. This can be accomplished by removing excess hydrogen from the shipping bag or system by mechanical means, chemical means, or a combination thereof. Examples of chemical methods of removing hydrogen include the use of hydrogen traps containing hydrogen-absorbing polymers or other compounds. Compounds suitable for use as Hydrogen absorbers are known in the art and are commercially available ("Hydrogen absorbers" (hydrogens) "National Laboratories, New Mexico, New Sangia, ReB Research & Consulting, Ferndale, Mich.). The compound may be present in the shipping bag or may be in direct communication with the cathode of the fuel cell.

Excess hydrogen can be limited by employing mechanical means, including the use of a shut-off valve or flow restrictor to modulate or shut off the flow of hydrogen into the shipping bag environment. Modulation of the hydrogen may be controlled by using an oxygen sensor connected to the hydrogen source to minimize or stop the hydrogen flow when the oxygen level falls below a minimum set point.

Yet another aspect of the invention provides a method for transporting and storing carbon dioxide absorbing oxidatively-degradable foodstuffs. The method utilizes a packaging module and system as described above. In a preferred embodiment, the method includes removing oxygen from the packaging module after inserting the carbon dioxide absorbing oxidatively decomposable food to create an oxygen reduced environment within the packaging module. In addition to the oxidatively decomposable food that absorbs carbon dioxide, the packaging module also contains a pressure-stable sealable shipping bag having limited oxygen permeability and an oxygen scavenger. The reduced oxygen environment within the packaging module is created by flushing the environment within the shipping bag, for example, by applying a vacuum and/or introducing a source of hypoxic gas for flushing the shipping bag. After flushing the shipping bag, the environment inside the shipping bag is a hypoxic environment. The shipping bag is filled with a low oxygen gas to provide an initial gaseous headspace such that the initial headspace comprises at least 30 volume percent of the shipping bag and the gas in the headspace comprises at least 99 volume percent of a gas other than oxygen. The pouches are then sealed.

In another aspect, the present invention provides a method for transporting and/or storing oxidatively degradable foodstuffs. This aspect provides the methods described herein to allow for the optional periodic removal of oxygen from the air environment surrounding the oxidatively degradable foodstuffs stored in individual shipping bags within the shipping container.

In a preferred embodiment, the invention comprises a method for removing oxygen from shipping bags having oxidatively decomposable foods, the method comprising:

a) a shipping bag having a sealable gas inlet port and a sealable gas outlet port, both ports being located in a headspace of the shipping bag, wherein the shipping bag comprises a flexible, collapsible, or expandable material that does not breach upon collapse or expansion;

b) adding oxidatively degradable foodstuff to the shipping bag in an amount that does not block the inlet and outlet ports;

c) sealing the transport bags;

d) injecting a sufficient source of hypoxic gas into the tote through the inlet port while venting gas through the outlet port in such a way as to effect one or more initial flushes of the tote with the gas source to provide a hypoxic atmosphere and a gas headspace with sufficient volume in the tote to allow gas to be absorbed into the food without increasing the oxygen content in the remaining gas headspace in the tote to a level above about 1500 ppm;

e) sealing the inlet and outlet ports; and

f) the shipping bags are optionally periodically flushed with a source of hypoxic gas so that sufficient gas headspace remains after flushing to compensate for gas absorbed into the food so that the oxygen concentration in the remaining gas headspace does not exceed 1500ppm at any given time.

The hypoxic gas source preferably comprises CO₂Or containing CO₂A gas mixture as one of its components. In a particular embodiment of the method of the present invention,the low oxygen gas source is 100% CO₂. In another embodiment, the hypoxic gas source is CO₂With nitrogen or another inert gas. Examples of inert gases include, but are not limited to, argon, krypton, helium, nitric oxide, nitrous oxide, and xenon. The composition of the hypoxic gas source can be altered to suit the food. For example, a hypoxic gas source for transporting and storing salmon is preferably 100% CO₂. Other fish such as tilapia preferably use 60% CO₂And 40% nitrogen as a source of hypoxic gas for storage or transport.

During transport and/or storage, the deaerator in the packaging module is operated so long as oxygen is present, so that the oxygen level is maintained below a level that would result in reduced freshness or spoilage of the material. This reduced oxygen level may be maintained during transport and/or storage by an oxygen scavenger. The oxygen level in the reduced oxygen environment is less than 1% oxygen, more preferably less than 0.1% oxygen, most preferably less than 0.01% oxygen.

After a period of time, the oxygen levels present in the shipping bag are still at reduced concentrations because the exchange of gas between the food and the environment of the shipping bag is naturally minimized or stopped. In one embodiment, the hypoxic gas source can be programmed to cease operation after an initial period of time sufficient to naturally minimize or cease gas exchange. Preferably, the hypoxic gas source is programmed to cease operation after a period of time of between about 0.5 hours and 50 hours; more preferably, the hypoxic gas source is programmed to cease operation after a period of time of between about 1 hour and 25 hours; more preferably, the hypoxic gas source is programmed to cease operation after a period of time of between about 2 hours and 15 hours; even more preferably, the hypoxic gas source is programmed to cease operation after a period of time of between about 3 hours and 10 hours.

Alternatively, the hypoxic gas source can be programmed to stop operating when the oxygen level reaches and remains below a predetermined concentration. In one embodiment, the oxygen level reaches and is maintained below 5% oxygen v/v, or the oxygen level reaches and is maintained below 1% oxygen v/v, or the oxygen level reaches and is maintained below 0.1% oxygen v/v, or the oxygen level reaches and is maintained below about 1500ppm oxygen.

In some embodiments, the initial flushing with the hypoxic gas source is sufficient to maintain a hypoxic environment during transport and/or storage of the oxidatively degradable foodstuff.

In embodiments where the fuel cell is present outside of the shipping bag, the module may be removed after an initial period of time sufficient to allow gas exchange to naturally minimize or cease, or when the oxygen level reaches and remains below a predetermined level according to the parameters discussed above. After the natural minimization or cessation of gas exchange between the food and the bag environment, any external source of gas to maintain positive pressure within the bag may also be eliminated, as the need to compensate for pressure variations within the bag is minimized.

In a preferred embodiment, the method relates to a system for transporting or storing an oxidatively decomposable material that absorbs carbon dioxide as described above. Thus, in a preferred embodiment, the method comprises transporting or storing one or more packaging modules in a single shipping container. In this embodiment, the individual packaging modules or shipping bags are individually removed from the system. This feature allows individual packing modules, or shipping bags of packing modules, to be delivered without disturbing the integrity of the remaining packing modules or shipping bags in the system.

The shipping bag, packaging module and/or system is then used to transport and/or store the oxidatively degradable material, such as oxidatively degradable food that absorbs carbon dioxide, for an extended period of time. Preferably, the long period is between 1 and 100 days; more preferably, the long period is between 5 and 50 days, even more preferably, the long period is between 15 and 45 days.

The methods set forth herein allow for the transport or storage of the oxidatively-degradable material for long periods of time that are not possible using standard MAP techniques or other standard food storage methods. The long period will vary depending on the nature of the oxidatively decomposable material. It is contemplated that fresh salmon may be stored or transported in a preserved manner for an extended period of at least 30 days using the methods disclosed herein. In contrast, fresh salmon can only be stored or transported in a preserved manner for a period of 10 to 20 days in the absence of an oxygen-reduced environment. (see examples).

Description of the specific embodiments

The following description sets forth specific embodiments that may be used in connection with the present invention. The specific embodiment is but one of the possible configurations and applications of the present invention and should not be taken as limiting in any way.

The invention is particularly suitable for transporting and storing fish, such as salmon. In particular, the present invention allows cultivated chile salmon to be transported to a destination in the united states by a transportation means. This length of transport (about 30 days) requires the use of the present invention to preserve the freshness of the salmon. Traditionally, chile salmon must be transported by air to reach the united states' destination before the salmon can spoil.

The salmon is prepackaged in a box. Each tank contains about 38.5 pounds of salmon. Sixty-four such cases are placed in a single shipping bag. The shipping bag is about 50 "X42" X130 ", 2" X50 "X130" or 48 "X46" X100 "in size and is made of a polyester/Nylon (poly/Nylon) blend material. The shipping bag size is increased by about 35% or 50% to provide sufficient gas headspace and allow for CO₂(and oxygen) absorption. The shipping bag has a pre-sealed end and a sealable end. The bag is placed on the tray with the pre-sealed end facing down. The tray is preferably covered with a protective sheet to protect and stabilize the shipping bags. Fifty-four cases of salmon are stacked in shipping bags. A schematic of a shipping bag is shown in fig. 1.

Another box, ideally of the same size as the salmon box, is added to the shipping bag. The cartridge contains one or more hydrogen fuel cells and a source of hydrogen. The hydrogen source is a balloon containing pure hydrogen. The bladder is configured to be in direct communication with the anode of the fuel cell such that the hydrogen fuel cell converts any oxygen present in the shipping bag to water for the duration of transport and/or storage.

The box also contains a fan to circulate air within the shipping bag, thereby promoting contact between the oxygen scavenger and the oxygen in the environment of the shipping bag. The fan is powered by the energy generated when the fuel cell converts oxygen to water or by a separate battery.

Furthermore, the cartridge contains a temperature recorder so that temperature changes can be recorded over the duration of transport and/or storage. Similarly, the cartridge contains an oxygen level recorder so that oxygen levels can be recorded for the duration of transport and/or storage. The cassette also contains an indicator that warns when the oxygen level within the pouch exceeds a prescribed maximum level or the temperature reaches a prescribed maximum level. In this particular embodiment, the indicator will issue a warning if the oxygen level exceeds 0.1% oxygen and if the temperature exceeds 38 ° F. The cartridge may further contain a monitor to monitor the level of hydrogen and fuel cell operation. The cartridge further optionally includes a visual indicator (e.g., an LED light) that indicates a problem with the device in the cartridge, and upon system arrival, if oxygen or temperature exceed limits, the cartridge preferably alerts the user using wireless communication (e.g., radio frequency transmission) as well as the visual indicator (e.g., an LED light).

Next, the salmon box is integrated with the box (stacked and taped) and the carrying bag is pulled upwards about all four sides of the integrated stack, gathering the open end of the carrying bag in a heat sealer. Gas scouring is carried out up to 100% carbon dioxide until the residual oxygen is less than about 5% v/v, and preferably less than about 1% v/v. The shipping bag is overfilled with carbon dioxide such that the initial headspace comprises about 50% or 30% by volume of the shipping bag. After the environment in the shipping bag has been so modified, a heat sealing cycle is initiated and the shipping bag is sealed to form a packaging module. The fuel cell is operated for the duration of transport and storage to remove any oxygen introduced into the packaging module by diffusion through the shipping bag material or at the shipping bag seal. The fish and packaging material within the packaging module also release small amounts of oxygen. The type of fuel cell used is a PEM fuel cell which does not require the use of any external power source to convert oxygen and hydrogen into water. See fig. 3.

The packaging module is loaded into the refrigerated transport along with other packaging modules configured as described. See fig. 2. The packaging module system is loaded onto a refrigerated transport. The transport vehicle transports salmon from Chile to the United States. Upon reaching the first destination in the united states, a number of packaging modules are removed from the delivery vehicle. Since each shipping bag contains a fuel cell for oxygen removal, the remaining packaging modules on the vehicle can be transported to other destinations by sea or by auxiliary land or air vehicles under reduced oxygen conditions.

Example 1

Two platform-type rigid containers were constructed, one with and one without a fuel cell. Two 9-liter plastic food storage containers with sealable lids were modified so that gas could be flushed and continuously introduced (at very low pressure) into each container. Commercially available fuel cell (hydro-Genius)^TMA removable Fuel Cell Extension Kit (manufactured by Fuel Cell Store) is installed into the lid of a 1-liter, 9-liter rigid container so that hydrogen can also be introduced directly from the outside of the rigid container to the (dead-end) anode side of the Fuel Cell. The cathode side of the fuel cell is fitted with a convection plate to allow the gas in the container to freely enter the fuel cell cathode. Sodium borohydride is purchased from a fuel cell website as a chemical source of hydrogen gas (when mixed with water). Sodium borohydride (NaBH)₄) The reactor was constructed from two plastic bottles so that hydrostatic pressure could be applied to constantly push hydrogen into the fuel cell and adjust for excess hydrogen production and consumption. This allows hydrogen to be generated and introduced into the fuel cell for long periods of time (days) without human supervision.

Carbon dioxide cylinders (gas), regulators, valves and pipes, and large household refrigerators were purchased. The refrigerator is provided with a pipe for continuously introducing external carbon dioxide into the rigid container and hydrogen into the fuel cell.

Testing a platform-based system in the following manner: with CO₂The initial oxygen level flush was reduced to around 1%, the outflow valve was closed with the inflow valve open, and both vessels were maintained at very low constant CO₂Under pressure. Use of (Dansheng (Dansensor)) CO₂Oxygen analyzer for measuring oxygen and CO over time₂Concentration while the fuel cell consumes the remaining oxygen from one vessel. It was determined that the container with the fuel cell was able to maintain oxygen levels below 0.1%, whereas the container without the fuel cell was unable to maintain oxygen levels below 0.3%.

On day 1, fresh atlantic chil salmon fillets were purchased directly from local (san City, CA) retail stores. Salmon were taken out of polystyrene foam (Styrofoam) containers with labels indicating that the (fat-free loin) was packed in chile 6 days ago. Retail personnel place 6 fish filets into retail display trays (2 filets per tray), wrap with stretch wrap, weigh and label each of the three trays.

The three packages were transported on ice to a laboratory where each tray was cut in half so that one half of each package could be directly compared to the other half for a different treatment. Placing the half-packs in three treatment groups; 1.) air control, 2.) 100% CO₂Without a fuel cell deaerator, 3) 100% CO₂There is a fuel cell deaerator. All three treatments were stored in the same refrigerator at 36 ° F for the duration of the test. Daily monitoring of oxygen and CO₂Levels, and sensory evaluations were performed as described below. After the initial removal of oxygen, the oxygen level is maintained at a level that is undetectable using the meter. The results are shown in table 2.

TABLE 2

The level of oxygen over the duration of the experiment is shown graphically in figure 4.

Sensory evaluation:

seven days after the three treatments were placed in the refrigerator, the air control was judged by odor to be slightly rancid and the level of rancid had been unacceptable at 36 ° F on day 8. Thus, starting with the air-control fillets, the total shelf life was approximately 13 days, and 7 days at 36 ° F (after storage at unknown temperature for the first 6 days).

At high CO₂After 22 days of ambient storage (plus 6 days before the start of the test), the fillets from both fuel cell and non-fuel cell treatments were removed from the container and evaluated by 4 sensory evaluators. The rating scale was 5-freshest, 4-freshest, 3-slightly freshess, 2-freshess, and 1-unacceptable. The raw sensory evaluation results are shown in table 3.

TABLE 3

6+22 days

After storage at 36 ° F for an additional 6 days, the remaining samples were photographed under natural conditions and the "no fuel cell" samples were considered unsuitable for consumption, mainly due to rancid odor (non-microbial spoilage) and extremely yellow meat color. The "fuel cell" samples were rated fresh for original color and odor (4). These samples were then cooked and evaluated for flavor and texture by 4 evaluators and rated fresh in both attributes (4). A visual comparison of salmon samples is presented in fig. 5.

In summary, after a total 34 day shelf life, the "fuel cell" samples were still rated fresh, while the "no fuel cell" samples were unacceptable.

Example 2

Fig. 7 shows a flexible shipping bag (as disclosed above) with an initial headspace of about 30% by volume shortly after gas flushing with carbon dioxide. Each of the shipping bags is approximately 42 "x 50" x 130 "and contains approximately 2,000 to 2,200 pounds of fish contained in 54 individual cartons. Other sizes of shipping bags may also be used, such as 50 "X42" X130 "or 48" X46 "X100" sized shipping bags. The shipping bag was first flushed with nitrogen (via valves and tubing). After about 8 hours or more, the shipping bag is flushed with carbon dioxide to achieve a very low oxygen level, followed by turning on the fuel cell. It is contemplated that nitrogen scouring may use only a single CO₂A flush event and a fuel cell. Holes (inflow and outflow) are cut (or installation piping may be used) to start the CO injection₂Flushed into shipping bags to obtain greater than 90% CO₂. Alternatively, a nitrogen flush may be used to reduce the oxygen level to about 1% oxygen, after which the valve is closed and waits at least 9 hours for the trapped oxygen to be released from the package and product. At this point (after 9 hours), the oxygen is typically raised to 1.5% to 2% and CO is used up to at least 90% (less than 1,500ppm oxygen)₂Flushing the shipping bag and closing the valve for shipping. Combining the following two facts makes it economically feasible to perform multiple gas flushes over a longer period of time: the process is performed "off-line" with 2,000 pound packages (rather than 40 pound packages) processed, while most MAP processes are performed "on-line".

Fig. 8 shows the same flexible shipping bag after 17 days of shipping and storage. The shipping bag allows for the initial presence of a high volume of CO within its interior₂To accommodate fish versus CO for the entire transport and handling/storage duration of the tote₂Absorption of (2). In addition, the initial gas headspace prevents the formation of negative pressure due to oxygen removal. It is important to note that these shipping bags did not leak and the degree of shrinkage seen in fig. 8 (relative to fig. 7) was due primarily to CO during 17 days of transport₂Absorption of (2). CO throughout transportation and storage₂Concentration maintenanceHigher than 90%. The freshness of the fish is then assessed.

FIG. 9 illustrates a shipping bag containing about 1 ton of fish, a hydrogen bladder, and a cartridge containing a fuel cell; an oxygen indicator that indicates whether the oxygen level in the shipping bag exceeds a level set forth as a reduced oxygen environment; and a monitor to monitor oxygen levels, hydrogen levels, fuel cell operation, and temperature. The cartridge further contains an LED light indicating a problem with any device in the cartridge; and a wireless warning system for warning the user if oxygen or temperature (time and temperature) exceeds a limit when the system arrives.

In summary, each shipping bag contained about 30% by volume of an initial headspace containing carbon dioxide. The gas in the shipping bag remains CO throughout transport and disposal₂Between 90% and 100%, thereby inhibiting microbial spoilage.

Example 3

Referring to fig. 10, wherein the shipping bag 1 includes a flexible oxygen impermeable barrier layer 3, an inlet port 5 and an outlet port 7, wherein the inlet port 5 is connected to a hypoxic gas source 9. The carrying bag 1 contains food (e.g. fish) 11 and a headspace 13. The headspace 13 allows the size of the carrying bag to be significantly increased relative to the food 11 contained therein. In one embodiment, the enlarged size provides up to 40% of the shipping bag's headspace by volume.

This unique configuration disclosed herein includes a shipping bag 1 and headspace 13 (see fig. 12) of significantly larger size, an inflow port (inlet) and an exhaust port (outlet), and gas scouring (as opposed to vacuum, followed by gas injection). Further, the shipping bag is loaded by placing the oxidatively decomposable food inside the shipping bag with the shipping bag on the pallet and the factory sealed end (closed end) at the bottom (rather than the factory sealed at the top as if the shipping bag were placed over the top of the food). Then, after the food is stacked or placed "inside" the shipping bag on the tray, the shipping bag is heat sealed at the top of the shipping bag (above the food). Gas scouring shipments using inflow ports (inlets) and exhaust ports (outlets) in the toteBag, thereby reducing oxygen. The gas inlet is located at the bottom of the tray and the gas outlet is located at the top of the opposite side (to facilitate top-to-bottom flushing). Valves or holes (taped) may be used for the inflow and/or outflow. When using CO₂(which is much heavier than air) can make CO₂Slowly flows into the bottom of the shipping bag to fill the shipping bag like a swimming pool, wherein the CO₂Pushing the air up and out of the exhaust. The final step after flushing is to inflate the headspace area of the shipping bag to maximize the head pressure and headspace of the shipping bag, then close the vent (outlet port) and shut off the hypoxic gas flow inlet (inlet). In CO₂After the concentration reaches 90 +% the gas flow is terminated and the shipping bag is held for hours to as long as one day or more to allow diffusion of the trapped oxygen out of the packaging and perishable contents so that subsequent flushing/filling will remove a substantial portion of the residual oxygen. A significant headspace increase in size is still required because of the CO₂The long duration of complete absorption and the additional reservoir (and slight positive pressure) created by the additional headspace can impede air leakage into the shipping bag (if there is a leak).

As shown in fig. 12, the shipping bag 1 also utilizes "top pressure," which is formed by the maximized headspace 13 height of the flexible shipping bag. CO believed to be confined in vertical shipping bags₂The altitude creates a positive pressure, as does an inflated balloon. Although the carrying bag is pressurized in fig. 12 not literally by stretching, it can be accomplished by constructing the carrying bag from a suitable material. In one example, the shipping bag is inflated to a pressure of about 2.2 inches of water or more above atmospheric pressure and the time to decay to about 1.8 inches of water is recorded to detect a leak. After the shipping bag passes the leak test (6 minutes or longer), then a gas flush is performed on the shipping bag and it is expected that the final gas flush may generate a pressure of about 0.5 inches of water or less. The shipping bag is "bulged" at this time. The plastic is configured to expand in a vertical manner and the methods and materials are known in the art. The initial shipping bag top pressure may be in the range of about 0.1 inches to about 1.0 inches of water or more above atmospheric pressure. In addition, the vertical constructionMinimizing horizontal space requirements is facilitated to carry the maximum number of trays side-by-side. The pouch expands no more than 20% in the horizontal direction, with the remaining gas expansion being in the vertical direction, thereby creating a "head pressure" and head space height.

In certain embodiments, the shipping bag is capable of accommodating extremely large head spaces (primarily accommodating CO)₂Absorb and protect against/delay air leakage) so that the combination of headspace and multiple initial gas flushes will not require continuous oxygen monitoring or further periodic gas flushes after the initial multiple gas flushes. It is contemplated that the initial gas flush may be performed periodically during the first 72 hours of the shipping bag being sealed and containing the oxidatively degradable foodstuff. Alternatively, the initial gas flush may be performed during the first 72 hours or less of sealing the shipping bag, or the first 60 hours, or the first 48 hours, or the first 24 hours.

Claims (77)

1. A packaging module useful for transporting and/or storing carbon dioxide-absorbing oxidatively-decomposable foodstuffs, comprising:

a) a pressure-stable, sealed shipping bag having limited oxygen permeability and defining a headspace, wherein said shipping bag is comprised of a flexible, collapsible, or expandable material that does not breach upon collapse or expansion;

b) an oxidatively decomposable food that absorbs carbon dioxide;

c) a fuel cell capable of converting hydrogen and oxygen into water;

d) a source of hydrogen; and

e) further wherein the initial headspace comprises at least 30 volume percent of the shipping bag and the gas in the headspace comprises at least 99 volume percent of a gas other than oxygen.

2. The packaging module of claim 1, wherein the gaseous headspace comprises at least about 90% carbon dioxide.

3. The packaging module of claim 1, wherein the gaseous headspace comprises from about 30% to about 35% of the interior volume of the shipping bag.

4. The packaging module of claim 1, wherein the gaseous headspace comprises about 35% of the total interior volume of the shipping bag.

5. The packaging module of claim 1, further comprising a holding element adapted to maintain a hydrogen source inside the tote.

6. The packaging module of claim 5, wherein the holding element for the hydrogen source in the tote is a cassette configured to hold the hydrogen source and the fuel cell.

7. The packaging module of claim 1, wherein the packaging module does not contain a gas source for maintaining a positive pressure within the packaging module during transport or storage.

8. The packaging module of claim 1, wherein the food is fish.

9. The packaging module of claim 8, wherein the fish is a fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike.

10. The packaging module of claim 9, wherein the fresh fish is salmon or tilapia.

11. The packaging module of claim 1, wherein the hydrogen source is selected from the group consisting of a gas-bag hydrogen source or a rigid container hydrogen source.

12. The packaging module of claim 1, wherein the hydrogen source is a gas mixture comprising carbon dioxide and less than 5 vol% hydrogen.

13. The packaging module of claim 1, further comprising a fan.

14. The packaging module of claim 12, wherein the fan is powered by the fuel cell.

15. A system useful for transporting and/or storing carbon dioxide-absorbing oxidatively-decomposable foodstuffs comprising one or more packaging modules, each packaging module comprising:

i) a pressure-stable, sealed shipping bag having limited oxygen permeability and defining a headspace, wherein said shipping bag is comprised of a flexible, collapsible, or expandable material that does not breach upon collapse or expansion;

ii) an oxidatively decomposable food that absorbs carbon dioxide;

iii) a fuel cell capable of converting hydrogen and oxygen into water;

iv) a source of hydrogen; and

v) additionally, wherein the initial headspace comprises at least 30% by volume of the shipping bag and the gas in the headspace comprises at least 99% by volume of a gas other than oxygen.

16. The system of claim 15, wherein the initial gaseous headspace comprises at least about 90% carbon dioxide.

17. The system of claim 15, wherein the initial gas headspace comprises from about 30% to about 35% of the interior volume of the shipping bag.

18. The system of claim 16, further comprising a temperature control system external to the packaging module, wherein the system maintains the temperature inside the module at a level sufficient to maintain freshness of the food.

19. The system of claim 16, wherein the packaging module further comprises a holding element adapted to maintain a hydrogen source inside the tote.

20. The system of claim 16, wherein the holding element for the hydrogen source in the tote is a cartridge configured to hold the hydrogen source and the fuel cell.

21. The system of claim 16, wherein the packaging module does not contain a gas source for maintaining a positive pressure within the packaging module during transport or storage.

22. The system of claim 16, wherein the food is fish.

23. The system of claim 22, wherein the fish is a fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike.

24. The system of claim 23, wherein the fresh fish is salmon or tilapia.

25. The system of claim 15, wherein the hydrogen source is a hydrogen-containing balloon.

26. The system of claim 15, wherein the hydrogen source is a gas mixture comprising carbon dioxide and less than 5% hydrogen by volume.

27. The system of claim 15, wherein the packaging module further comprises a fan.

28. The system of claim 27, wherein the fan is powered by the fuel cell.

29. A method for transporting and/or storing an oxidatively decomposable food that absorbs carbon dioxide, comprising:

a) removing oxygen from a packaging module containing an oxidatively decomposable food that absorbs carbon dioxide to create an oxygen-reduced environment within the packaging module, the packaging module comprising: a pressure stable sealable shipping bag having limited oxygen permeability and defining a headspace, wherein said shipping bag is comprised of a flexible, collapsible or expandable material that does not rupture upon collapse or expansion; a fuel cell; and a source of hydrogen;

b) flushing the shipping bag with an inert gas such that the shipping bag comprises an initial gaseous headspace, wherein the initial headspace comprises at least 30 volume percent of the shipping bag and the gas in the headspace comprises at least 99 volume percent of a gas other than oxygen;

c) sealing the shipping bag;

d) operating the fuel cell during transport or storage to convert oxygen to water by hydrogen present in the shipping bag to maintain the reduced oxygen environment within the shipping bag; and

d) transporting or storing the material in the shipping bag.

30. The method of claim 29, wherein the initial gaseous headspace comprises at least about 90% carbon dioxide.

31. The method of claim 29, wherein the initial gas headspace comprises from about 30% to about 35% of the total interior volume of the shipping bag.

32. The method of claim 29, wherein the transporting or storing is for a period of between 5 days and 50 days.

33. The method of claim 32, wherein the transporting or storing is for a period of between 15 days and 45 days.

34. The method of claim 32, further comprising maintaining a temperature in the shipping bag sufficient to maintain freshness of the material during transport or storage.

35. The method of claim 29, wherein the packaging module further comprises a holding element adapted to maintain a hydrogen source inside the tote.

36. The method of claim 35, wherein the holding element for the hydrogen source in the tote is a cartridge configured to hold the hydrogen source and the fuel cell.

37. The method of claim 29, wherein the reduced oxygen environment comprises less than 1% oxygen.

38. The method of claim 37, wherein the reduced oxygen environment comprises less than 0.1% oxygen.

39. The method of claim 29, wherein the reduced oxygen environment comprises carbon dioxide.

40. The method of claim 29, wherein the reduced oxygen environment comprises carbon dioxide and hydrogen.

41. The method of claim 29, wherein the reduced oxygen environment comprises nitrogen.

42. The method of claim 29, wherein the reduced oxygen environment comprises carbon dioxide, nitrogen, and hydrogen.

43. The method of claim 29, wherein the food is fish.

44. The method of claim 43, wherein the fish is a fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike.

45. The method of claim 44, wherein the fresh fish is salmon or tilapia.

46. The method of claim 29, wherein the hydrogen source is a balloon containing hydrogen.

47. The method of claim 29, wherein the hydrogen source is a gas mixture comprising carbon dioxide and less than 5 vol% hydrogen.

48. The method of claim 29, wherein the fuel cell is programmed to cease operation after an initial period of time sufficient to allow gas exchange to naturally minimize or cease.

49. The method of claim 48, wherein the initial period of time is between about 0.5 and 50 hours.

50. The method of claim 48, wherein the fuel cell is programmed to stop operating when oxygen levels reach and remain below a predetermined level.

51. The method of claim 50, wherein the predetermined oxygen level is less than 5% oxygen v/v.

52. The method of claim 50, wherein the predetermined oxygen level is less than 1% oxygen v/v.

53. A method for transporting and/or storing an oxidatively decomposable food that absorbs carbon dioxide, comprising:

a) obtaining a pressure stable sealed shipping bag having limited oxygen permeability and defining a headspace containing an oxidatively decomposable material that absorbs carbon dioxide, wherein the initial headspace comprises at least 30 volume percent of the shipping bag and the gas in the headspace comprises at least 99 volume percent of a gas other than oxygen, further wherein the shipping bag is comprised of a flexible, collapsible or expandable material that does not breach upon collapse or expansion, and further wherein the shipping bag is connected to a module comprising a fuel cell and a hydrogen source such that the anode of the fuel cell is in direct communication with the environment of the shipping bag;

b) operating the fuel cell during transport or storage to convert oxygen in the shipping bag to water by the fuel cell; and

c) transporting or storing the material in the shipping bag.

54. The method of claim 53, wherein the initial gaseous headspace comprises at least about 90% carbon dioxide.

55. The method of claim 53, wherein the initial gaseous headspace comprises from about 30% to about 35% of the interior volume of the shipping bag.

56. The method of claim 53 wherein the module is disconnected from the shipping bag after an initial period of time sufficient to allow gas exchange to naturally minimize or cease.

57. The method of claim 56, wherein the initial period of time is between about 0.5 and 50 hours.

58. The method of claim 53 wherein the module is disconnected from the shipping bag when oxygen levels reach and remain below a predetermined level.

59. The method of claim 58, wherein the predetermined oxygen level is less than 5% oxygen v/v.

60. The method of claim 59, wherein said predetermined oxygen level is less than 1% oxygen v/v.

61. A method for removing oxygen from shipping bags having oxidatively-degradable foodstuffs, the method comprising:

a) a shipping bag having a sealable gas inlet port and a sealable gas outlet port, the two ports being located in a headspace of the shipping bag, wherein the shipping bag comprises a flexible, collapsible, or expandable material that does not breach upon collapse or expansion;

b) adding oxidatively decomposable food to the shipping bag in an amount that does not block the inlet and outlet ports;

c) sealing the shipping bag;

d) injecting a sufficient source of hypoxic gas into the tote through the inlet port while venting gas through the outlet port in such a way as to effect one or more initial flushes of the tote with the gas source to provide a hypoxic atmosphere and a gas headspace with sufficient volume in the tote to allow gas to be absorbed into the food without increasing the oxygen content in the remaining gas headspace in the tote to a level above about 1500 ppm;

e) sealing the inlet and outlet ports; and

f) optionally periodically flushing the shipping bag with a source of hypoxic gas so as to maintain sufficient gas headspace after flushing to compensate for gas absorbed into the food so that the oxygen concentration in the remaining gas headspace does not exceed 1500ppm at any given time.

62. The method of claim 61, wherein the headspace of the shipping bag comprises from about 20% to about 40% of the interior volume of the shipping bag.

63. The method of claim 61, wherein the tote further comprises an oxygen sensor.

64. The method of claim 61, wherein the hypoxic gas comprises carbon dioxide.

65. The method of claim 61, wherein the reduced oxygen environment comprises carbon dioxide.

66. The method of claim 61, wherein the reduced oxygen environment comprises nitrogen.

67. The method of claim 61, wherein the reduced oxygen environment comprises carbon dioxide and nitrogen.

68. The method of claim 61, wherein the food is fish.

69. The method of claim 68, wherein the fish is a fresh fish selected from the group consisting of: salmon, tilapia, tuna, shrimp, trout, catfish, sea bream, sea bass, striped bass, red drum, pompano, haddock, dog cod, halibut, Atlantic cod, and pike.

70. The method of claim 69, wherein the fresh fish is salmon or tilapia.

71. The method of claim 61, wherein the hypoxic gas source is programmed to cease operation after an initial period of time sufficient to allow gas exchange to naturally minimize or cease.

72. The method of claim 71, wherein the initial period of time is between about 0.5 and 50 hours.

73. The method of claim 61, wherein the shipping bag comprises an initial "top pressure" of about 0.1 inches to about 1.0 inches of water above atmospheric pressure.

74. A method for transporting and/or storing an oxidatively degradable foodstuff comprising:

a) removing oxygen from a shipping bag containing oxidatively-degradable foodstuff to create a reduced oxygen environment, the shipping bag comprising: a flexible, collapsible or expandable material having limited oxygen permeability and not cracking upon collapse or expansion; a sealable gas inlet port and a sealable gas outlet port, the two ports located in a headspace of the shipping bag; and a hypoxic gas source in gas communication with the shipping bag;

b) sealing the shipping bag;

c) optionally periodically flushing the shipping bag with a source of hypoxic gas so as to maintain sufficient gas headspace after flushing to compensate for gas absorbed into the food so that the oxygen concentration in the remaining gas headspace does not exceed 1500ppm at any given time; and

d) transporting or storing the food in the shipping bag.

75. The method of claim 74, wherein said transporting and/or storing is for a period of time between 5 days and 50 days.

76. The method of claim 74, wherein said transporting and/or storing is for a period of time between 15 days and 45 days.

77. The method of claim 74, wherein the shipping bag comprises an initial "head pressure" of about 0.1 inches to about 1.0 inches of water above atmospheric pressure.