NL9201178A - METHOD, COMPOSITION AND APPARATUS FOR DISINFECTING RAW MATERIALS, PRODUCTS AND PRODUCTION PRODUCTS, IN PARTICULAR IN THE FOODSTUFFS INDUSTRY. - Google Patents

Abstract

A mixture of hydrogen peroxide and glycerol was found to be a particularly effective composition for disinfecting raw materials (base materials), in particular foodstuffs. An organic acid, such as valeric acid, can be added to the mixture as a stabilizer. Atomization of the mixture, in conjunction with the product to be disinfected being gently shaken in an apparatus provided with means suitable for this purpose, effects efficient disinfection in conjunction with relatively low consumption of the mixture. The shelf life of the disinfected products can be further increased by these being dried on the surface by means of sterile air.

Description

Method, composition and device for the disinfection of raw materials, products and means of production, in particular in the food industry.

The invention relates to a method for disinfecting raw materials, products and production means, in particular of water and materials and equipment in the food industry, using hydrogen peroxide.

The invention also relates to a fumigant which can be used in this method.

Contamination of raw materials and processed products with harmful biological material is increasingly seen as an objection to public health and the environment. Stricter requirements with regard to bacteriological status are increasingly being imposed on materials and equipment used in the food industry. The problem is especially urgent in, for example, food industry processes involving conveyor belts and the like, and at room temperature, because controlling and controlling germs and other harmful components is difficult.

It is known to improve the shelf life of foods by adding chemicals. For example, according to US patent 2053740, hydrogen peroxide can be added to milk and cream, or substances can be added to foodstuffs which develop hydrogen peroxide under the action of enzymes (German patent 2420135). Single and multiple alcohols have also been used for food processing (EP-A-169927, DE-A-2119351, GB-A-1273938 and GB-A-1375704). Also well known is the addition of sulfite to keep food contamination at an acceptable level. Chlorine is often used to clean and disinfect production equipment. The use of chemicals also implies the danger of too high a dose, which can sometimes cause carcinogenic or allergenic effects. The use of chlorine can also lead to corrosion of metal-containing devices, which in itself can again be a source of contamination with bacteria, a further drawback of the chemical agents used so far is that the excess thereof is carried along with cleaning water and thus a load of can shape the environment.

A solution to such problems has been sought in working in a sterile room or in using waste water treatment. Such water purification plants are usually designed on the basis of the average water quality, the bacteriological load and the effluent standards. Faults in production often lead to overloading the installation, so that chemicals have to be resorted to again to meet the product requirements. This leads to a sometimes unacceptable increase in costs and environmental impact.

There is therefore a great need for an inexpensive and simple method of disinfecting raw materials, products and production means, as well as process water from such production. We have found a method, a composition and a device with which this need can be met.

The method according to the invention as described in the preamble is characterized for this purpose in that the raw materials, products and / or production means are treated with a mixture of hydrogen peroxide and glycerol.

In particular, the materials are treated with a solution of hydrogen peroxide and glycerol in a ratio between 1: 1 and 10: 1, more particularly between 2: 1 and 5: 1, in water.

Preferably, a solution is used which, in addition to hydrogen peroxide and glycerol, also contains an organic acid as a stabilizer, such as acetic acid, lactic acid, benzoic acid or hexanoic acid, and in particular valeric acid (pentanoic acid). This organic acid is preferably present in an amount of 1-5% by weight relative to the hydrogen peroxide.

Preferably the means or materials are disinfected by spraying the above-mentioned solution in the space in which they are located under overpressure. This way of disinfection / preservation works very efficiently with a very low consumption of disinfectant, because disinfection takes place in the gas phase. The food does not suffer any damage from the disinfectant.

When disinfecting foodstuffs, an amount of the solution is preferably used such that 0.1-1 g hydrogen peroxide is used per kg of foodstuff.

In particular, the disinfection takes place at a temperature between 5 and 70 ° C for about 1 minute to about 1/2 hour, depending on the treatment temperature and the concentration of the solution in the room.

In order to further increase the shelf life of products treated with disinfectant according to the invention, such as for instance foodstuffs, the invention provides in a further embodiment for drying disinfected products on the surface by means of sterile air, whether or not heated above room temperature. An important condition to prevent bacterial division is the removal of water from the treated products. After all, a waterless surface is a bad environment for the bacteria.

Due to the coating which the disinfectant forms on the treated product, the liquid level (water level) of the product will not be affected, if at all, by drying. In a still further embodiment of the method according to the invention, in order to improve the adhesion of the disinfectant to the product, the product treated with the disinfectant is only subjected to the drying step after a certain period of time.

The disinfectant according to the invention is characterized in that it consists of a solution of hydrogen peroxide and glycerol in water, preferably demineralized water. The weight ratio between hydrogen peroxide and glycerol is preferably between 1: 1 and 10: 1, more preferably between 2: 1 and 5: 1. The solution preferably contains 10-50 wt.%, In particular 25-35 wt.%, Hydrogen peroxide.

Preferably, the solution also contains a stabilizing agent in the form of an organic acid. The organic acid is, in particular, valeric acid, in an amount of 1-5% by weight relative to the hydrogen peroxide.

According to the invention, hydrogen peroxide is used as the basis for the disinfectant. The use of this agent is already known per se, but it has hitherto been little used in the food industry and where it has been used it has been used as an additive to the foodstuff. A problem of hydrogen peroxide is that it decomposes quickly so that its addition has little effect unless high concentrations are used. An example of such a use of hydrogen peroxide is described in the aforementioned United States Patent Specification 2053740 and the also already mentioned German Patent Specification 2420135.

The surprise of the present invention is that when hydrogen peroxide is mixed with glycerol, and optionally a stabilizing acid such as valeric acid, in a solution of preferably demineralized water, and this solution is sprayed on or around the raw or processed foods or devices, a effective disinfection takes place, essentially eliminating all bacteria and germs and the like. Demineralized water means water from which minerals and organic substances have been removed.

The disinfectant action also occurs when materials or objects are directly exposed to an aqueous solution. Thus, for example, parts of production means, which cannot be subjected to a spraying treatment, can be disinfected with the mixture and further process water and domestic waste water can also be disinfected by adding the mixture in liquid, optionally further concentrated form. Disinfection with the composition according to the invention can therefore take place in various ways, for example by spraying, irrigating, dipping, rinsing, etc. Spraying can also take place according to the principle of a humidifier and can be used for the storage of foodstuffs, for example in cooling or freezer rooms for storage. food such as potatoes, or without special refrigeration facilities.

The disinfectant effect of hydrogen peroxide is based on the splitting of hydrogen peroxide into water and oxygen. Normally, this cleavage proceeds quickly at room temperature, and even faster at elevated temperature, and hydrogen peroxide also evaporates, so that the residence time of hydrogen peroxide is too short to disinfect large quantities of foodstuffs. Surprisingly, the addition of glycerol has been found to delay the cleavage of hydrogen peroxide such that the action of the disinfectant is greatly improved.

The glycerol used here should be as pure as possible and preferably of a quality allowed for use in the food industry.

A further improvement of the effect appears to be achieved by adding an organic acid. This organic acid can be a carboxylic acid such as benzoic acid, acetic acid, propionic acid and higher fatty acids, or a mono- or dihydroxycarboxylic acid such as lactic acid. A carboxylic acid that has been found to give a special improvement in the effect is valerian acid. This is also preferably used in a quality permitted in the food sector. When the mixture of hydrogen peroxide, glycerol, and optionally valeric acid, is atomized in the space around the materials to be disinfected, this is preferably done such that the concentration of hydrogen peroxide in the air is 0.001 to 0.01% by volume. The treatment time depends on the concentration of the mixture in the atmosphere and on the temperature. For example, at a concentration between 0.001 and 0.005% by volume and a temperature of 5 to 25 ° C, the treatment time will usually be between 2 and 5 minutes. When disinfected with the mixture as a solution with a concentration of 0.2-0.3 wt% hydrogen peroxide and a temperature of 50 to 60 ° C, the treatment time will usually be between 5 and 30 minutes.

The mixture of hydrogen peroxide, glycerol and optional organic acid according to the invention is a clear and almost odorless liquid that reacts slightly acidic. The mixture has a wide disinfecting effect and makes Gram-positive bacteria, fungi and algae harmless, prevents mucus and does not foam. Disinfection of foods with the mixture does not give any odor, discoloration or taste. The mixture can be used throughout the food industry, in the production, processing and storage of food.

The invention also relates to a device for performing the above-described method in a simple and inexpensive manner. The device can be used in both large and small production units. The device according to the invention comprises a transport means for the material or product to be treated and at least one disinfection chamber in which the material or product can be passed, and characterized in that the disinfection chamber is provided with means for spraying and / or spraying a liquid disinfectant as well as means for dosing, pumping and removing the disinfectant.

With a view to efficient use of the disinfectant, a further embodiment of the device according to the invention is characterized in that it comprises two or more connected disinfection chambers or rooms, wherein means are also provided with which disinfectant that leaves a room can enter another room. be entered.

In yet a further embodiment of the device according to the invention, the transport means is a mesh-shaped conveyor belt, wherein the disinfection chamber has openings for the conveyor belt at both ends and in which the chamber is provided with a holder for disinfectant, a dosing pump, a blower and an air / liquid mixer connected to a conduit for supplying a disinfectant-air mixture to the disinfection chamber, and further equipped with an internal conduit system consisting of one or more conduits connected to spray tubes having openings for atomized delivery disinfectant in the disinfection chamber, which is also equipped with a drain.

In order to bring the product into optimum contact with the disinfectant, a vibrating device or vibrating frame is also provided, with which the product is shaken slightly in the disinfection chamber. In such a way that no damage or settling occurs and the product does not jump off the means of transport.

In the preferred embodiment of the device according to the invention, there is also provided a drying chamber arranged after the disinfection chamber, for drying the surface of the disinfected product with sterile air. Here, too, a vibrating device or vibrating frame can be used for slightly shaking the product. This is to achieve optimal drying.

In yet a further embodiment of the device according to the invention, in order to effect a good adhesion of the disinfectant to the product, a rest chamber is arranged between the disinfection chamber and the drying chamber. The conveyor belt can advantageously extend as a single belt through the said chambers.

With regard to the device according to the invention, it can be noted that it can be of relatively simple design, consisting of a disinfection chamber, in which means for supplying the mixture and for mixing it with air, wherein the temperature, which is preferably can be controlled, and the dimensions of the room are adapted to the desired application. Disinfection can take place in that the materials are guided through the disinfection chamber at a suitable, adjustable speed. By adding a drying chamber and, if desired, a resting chamber, a further increase in, for example, the shelf life of a disinfected food product can be achieved.

The invention is particularly suitable for the disinfection of lightly perishable goods, such as fish and other sea animals. Meat products can also be disinfected with the method according to the invention without affecting the quality, color, nutritional value or taste thereof. The shelf life can thus be extended significantly. Process water from the food industry can also be treated with the method according to the invention and purification can thus be achieved such that the environmental requirements are met.

Fig. 1 schematically shows a side view of a preferred embodiment of a device suitable for carrying out the method according to the invention.

Fig. 2, 3 and 4 schematically show cross-sectional views of the device according to Fig. 1.

Fig. 5 schematically shows an arrangement for an application of the method according to the invention.

The device according to fig. 1 consists of a mesh-shaped stainless steel or plastic conveyor belt 1 with an adjustable electric drive motor 6 which is placed in a frame or frame 2 with adjustable legs 3. Conveyor belt 1 passes through a disinfection chamber 4 of stainless steel with a drain 5 Outside the chamber 4 itself, but in fixed connection therewith, there is a liquid container 7 for the disinfectant. The container is connected via lines 8 to a high-pressure pump 9 and an air / liquid mixer 10 with blower 11, and is further connected to a number of tubes 12 running parallel to the conveyor belt, which distribute the mixture over the disinfection chamber 4 and some to the parallel tubes 12 connected transverse tubes 13 which are provided with spray nozzles 14 and which ensure an even dispersion of disinfectant throughout the chamber 4. This arrangement ensures that material which is on the conveyor belt 1 from all sides of the disinfectant is exposed. All parts of the device are electrically powered. Depending on the product to be treated, the tubing can be made of stainless steel or, for example, high-quality plastic.

In order to ensure that the products to be disinfected are brought into full contact with the disinfectant, the belt 1 in the preferred embodiment of the device according to the invention runs over a vibrating frame 15. This vibrating frame 15 is preferably vibrated with an electromagnetic vibrator 16. The vibration is set so that the product is shaken slightly without damaging it. So without the product jumping on the belt or settling in.

The mixture of hydrogen peroxide, glycerol and optionally valeric acid in demineralized water is passed to the mixer 10 by means of the pump 9. At the same time, blower 11 blows air into the mixer 10 under overpressure. The disinfection mixture is then sprayed over the material on the conveyor belt 1 via the spray system 14 on the inside of the disinfection chamber 4.

The air to be used is drawn in via an air-clean air filter. Intimate mixing of the sterile air and the liquid disinfectant takes place in the mixer 10, the disinfectant being injected axially into the air stream. The composition of the air / disinfectant mixture can be adjusted, for example, by varying the pump opening.

The movement of the conveyor belt 1 with the atomization of the air / disinfection liquid mixture in the disinfection chamber 4 gives an optimal treatment of the materials with the disinfection mixture according to the invention. The conveying speed of the belt 1 depends, inter alia, on the product to be treated, its bacteriological condition and the desired degree of preservation. An overpressure in the disinfection chamber 4 prevents the entry of contaminating air into the chamber. Disinfectant mixture that leaks from the disinfection chamber into the space of the production line will have an additional disinfectant effect here and thus achieve a cleaner production.

The liquids dripping from the product to be disinfected are collected in a drip pan 17 placed under the conveyor belt 1. This is to prevent potential contamination of the floor 18 under the frame 2. The liquids in question run to a condensate filter reservoir 19. In this reservoir 19, any solid parts (from the product to be disinfected) are separated from the liquids by means of a screen plate 20. The residual liquids then flow via the discharge 5 to a receptacle 21.

When a possible packaging device is arranged immediately after the disinfection chamber 4, the packaged products will be able to contain little or no contaminating germs.

In the preferred embodiment, the device according to the invention further comprises a drying chamber 22, in which the product treated with the disinfectant in the disinfection chamber 4 is stripped by means of sterile air of the residual liquid still hanging on the outside of the product. In the drying chamber 22 there is also arranged a vibrating frame 23 over which the conveyor belt 1 runs and which is driven via an electromagnetic vibrator 24. The vibrating frame 23 ensures that, by shaking the product slightly, the drying air comes into contact optimally with the surface of the product. The drying air is drawn in from the production space by means of a blower 25 via an air-clean filter 26. The sterile air is then introduced into the drying chamber 22 via a pipe system 27. The amount and, if desired, the temperature of the air are adjusted to the product to be dried, i.e. the amount of adhering liquid, by controlling the blower 25 and heating means (not shown).

To improve or optimize the adhesion of the disinfectant to the product, a rest chamber 28 is preferably placed between the disinfection chamber 4 and the drying chamber 22. In the preferred embodiment of the device according to the invention, the resting room 28 is in the form of a tunnel, through which the conveyor belt 1 passes. In this tunnel, the disinfectant adheres further to the product and the free disinfectant is partially decomposed. The drip pan 17 mounted under the conveyor belt 1 here extends from under the disinfection chamber 4 past the rest chamber 28 to the drying chamber 22.

In order to discharge the oxygen molecules released during the decomposition, vents 29 are mounted on the rest chamber 28. These do release pressure but prevent the entry of polluted air from the outside. The drying air which has been in contact with the product in the drying chamber 22 will leave the drying chamber through its overpressure via a vent 30 mounted at the top of this. This vent 30, like the vent 29 of the resting chamber 28, is also provided with an overpressure protection or non-return valve, which can be adjusted to a specific pressure. This is to ensure a minimum overpressure in the resting drying chamber.

The housing of the drying chamber 22 and the resting chamber 28 is preferably made of stainless steel or high-quality plastic. The resting chamber 28 may also be made of transparent plastic for visual inspection. The tubing 27 of the drying chamber 22 is, from a cost-technical point of view, preferably made of plastic tube. The outlets 31 of the tubes 27 are arranged such that all sides of the product come into direct contact with the drying air. When the product leaves the drying chamber 22, it is ready to be packaged or stored in vacuum, gas, or otherwise. In addition to the disinfection treatment, the shelf life of, for example, a food has greatly increased due to the additional drying process, without any significant adverse effect on the taste, nutritional value, color, weight, etc. of the product.

Fig. 2 shows a partial section through the disinfection chamber 4, taken along the line II-II in FIG. 1. FIG. 3 is a partial sectional view through the rest chamber 28 taken along line III-III in FIG. 1. FIG. 4 shows a section along line IV-IV of the drying chamber 22 shown in FIG. 1. The arcuate arrangement of the air outlets 31 in the drying chamber 22 can be clearly seen, in order to effect an all-round contacting of drying air and product.

In a practical embodiment of the device according to the invention, the air / liquid mixer 10 is constructed in such a way that the air leaving the mixer 10 does not release the absorbed liquid when it leaves the mixer, which for this purpose has a parabolic shape with on the inside a screw. The storage container 7 is made of stainless steel; the collection container 21 of plastic and the frame also of stainless steel, such as stainless steel 312 or 304. The air filters in the blower 11 and the drying chamber are designed as air-clean filters, consisting of a flint filter, electrostatic filter, an active carbon filter and an ionizer .

Such a disinfection arrangement consisting of a disinfection chamber 4 and optionally a rest chamber 28 and drying chamber 22 with accessories as set out above can be adapted to different sizes and types of production lines, is mobile, relatively inexpensive to purchase, easy to operate and thus quickly cost effective.

In the production line shown in Fig. 5, consumption mussels are prepared. The production line consists of a cooking appliance or autoclave 32, a vibrating or shaking appliance 33 for de-shelling the mussel, a rinsing bath 34 with conveyor belt 35, a reading or sorting belt 39 with waste bin 49 and a conveyor belt 40 placed in a disinfection chamber 4 with sputtering arrangements as described in FIG. 1. The various units are arranged among themselves as shown. The products i.e. the mussels move in the direction of the arrow. The shaker 33 and the rinsing bath 34 are connected via lines 47 and 48, respectively, to a reservoir 36 for collecting waste products. The disinfection chamber 4 is connected to a collection reservoir 37. With the aid of a pipe system and pumps, the collected disinfection mixture is reused at other places in the production line, for example the shaker 33.

Fresh disinfection mixture according to the invention, mixed in a suitable concentration with demineralized water, is supplied via an inlet 38 to the rinsing bath 34 for rinsing the de-shelled product. The rinse mixture is mixed with clean air via air inlets 50 in the rinse bath 34 and is fed via a pump 41 and a pipe system 42 to a sprayer 43, which is located above the shaker 33, and is additionally pressurized in the disinfection chamber 4 atomized. The disinfectant from the disinfection chamber 4 is collected in the reservoir 37 from which a part with a pump 44 can be passed through a pipe system 45 to a dripper 46 located after the sorting belt 39 and another part under pressure again in the disinfection chamber 4 can be atomized. If desired, several disinfection chambers 4 can be used one after the other, while after the conveyor belt 40 a rest chamber 28 and drying chamber 22 according to Fig. 1 can also be arranged.

The advantage of rinsing the product with fresh disinfectant is that the total amount of disinfectant is significantly reduced and disinfectant already used is used for partial disinfection of the product at an early stage of the production line, in this case at the shaker 33 and after the sorting belt. 39. Thus, about 80% of the bacteria and germs can already be removed before treatment in the disinfection chamber 4, and the remaining about 20% are disinfected in the chamber 4 and with possible after-rinse with (fresh) disinfectant (not shown) ). In the reservoir 36, any living bacteria can strip the waste water of proteins, such that the waste water becomes foam-free. This disinfection process gives an effluent that does not harm the environment.

The results of controls on the mussel production line that have undergone the described disinfection process indicated a number of contamination germs of 60-100 germs / g product, Enterococcus sp. less than 10 bacteria / g product and Staphylococcus sp. less than 50 bacteria / g product.

In the poultry sector, the invention is ideally suited for releasing salmonella from consumption and hatching eggs.

Claims (21)

A composition for disinfecting raw materials, products, water and / or production means, in particular in the food industry, which composition contains hydrogen peroxide, characterized in that the composition contains a mixture of hydrogen peroxide and glycerol. Composition according to claim 1, characterized in that the composition contains a solution of hydrogen peroxide and glycerol in a weight ratio of 1: 1 to 10: 1, preferably from 2: 1 to 5: 1, in water. Composition according to claim 2, characterized in that it contains 10-50, preferably 25-35 wt.% Hydrogen peroxide. Composition according to any one of claims 1 to 3, characterized in that it also contains an organic acid. Composition according to claim 4, characterized in that the organic acid is valeric acid. Composition according to claim 4 or 5, characterized in that it contains 1 to 5% by weight of organic acid relative to the hydrogen peroxide. Method for disinfecting raw materials, products, water and / or production means, in particular in the food industry, using hydrogen peroxide, characterized in that the composition according to any one of claims 1-6 is used. Method according to claim 7, characterized in that the composition is atomized in the space around the materials and / or agents. Process according to claim 8, characterized in that a concentration of 0.001 to 0.01, in particular 0.001 to 0.005,% by volume of hydrogen peroxide is applied in the room. Method according to any one of claims 7-9, characterized in that the disinfection is carried out at a temperature of 5-70 ° C for 1 to 30 minutes. Method according to any one of claims 7-10, characterized in that an amount of the composition corresponding to 0.1-1 g hydrogen peroxide per kg raw material or product is used for the disinfection of raw materials or products. A method according to any one of claims 7-11, characterized in that the disinfected product is dried on the surface with sterile air. Method according to claim 12, characterized in that the disinfected product is dried after a certain period of time. Device for carrying out the method according to any one of claims 7-13, comprising a transport means for the material or product to be treated and at least one disinfection chamber in which the material or product can be passed, characterized in that the disinfection chamber is provided with means for spraying and / or spraying a liquid disinfectant, as well as means for dosing, pumping and removing the disinfectant. Device as claimed in claim 14, characterized in that it comprises two or more connected disinfection chambers or rooms, wherein means are also provided with which disinfectant leaving one room can be introduced into another chamber. Device according to claim 14 or 15, characterized in that the transport means is a mesh-shaped conveyor belt, that the disinfection chamber has openings for the conveyor belt at both ends and that the chamber is provided with a holder for disinfectant, a dosing pump, a blower and an air / liquid mixer connected to a line for supplying a disinfectant-air mixture to the disinfection chamber, and further of an internal piping system consisting of one or more lines connected to spray tubes having openings for the administration of atomized disinfectant into the disinfection chamber, which is further provided with a drain. Device according to claim 14, 15 or 16, characterized in that a vibrating device is arranged in the disinfection chamber, for shaking up the material or product to be disinfected during spraying or spraying the disinfectant. Device according to any one of claims 14-17, characterized by a drying chamber, provided with means for drying the disinfected material or product on the surface by means of sterile air. Device according to claim 18, characterized in that a vibrating device for shaking up the material or product to be dried is arranged in the drying chamber. A device according to claim 18 or 19, characterized in that a resting chamber is arranged between the drying chamber and the disinfection chamber. Device as claimed in claim 18, 19 or 20, characterized in that the transport means is a conveyor belt passing through said chambers.