JPH0220270A - Releasing agent of carbon dioxide gas - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a carbon dioxide releasing agent that can be used to maintain the freshness of livestock products, fruits and vegetables, and the like.

[Conventional technology]

It is well known that the use of 002 gas is effective in preserving the freshness of livestock products such as eggs and meat, and fruits and vegetables such as vegetables and fruits. For example, when CO2 gas is used to maintain the freshness of eggs, the solubilization of concentrated egg whites is prevented and the product value is improved. The same applies to vegetables and fruits, and the chondral atmosphere storage method (CA storage method) has been put into practical use as a preservation method using CO□ gas.

[Problem to be solved by the invention]

However, these methods mechanically control the COt gas concentration to a constant level, and therefore require investment in equipment, resulting in high costs. Therefore, it has been desired to develop a means to more easily maintain freshness.

[Means to solve the problem]

The present invention was made in response to such a need, and it is possible to achieve this purpose by combining a carbonic acid-containing substance with a hygroscopic substance and an acidic substance to gradually release CO2 gas. This was done by discovering the following.

Substances containing carbonic acid are usually solid carbonates.

Carbonates include sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, sodium carbonate, calcium carbonate,
It may be a salt of an inorganic substance such as potassium carbonate, or a salt of an organic substance such as a carbonate type anion exchange resin. Further, the substance containing carbonate may be a substance containing carbonate, such as a shell. The carbonic acid-containing substance is not limited to carbonates, but any substance that releases carbon dioxide gas through a solid phase reaction with an acidic substance can be used. This carbonic acid-containing substance needs to be mixed uniformly with an acidic substance, and therefore, at least when mixed with an acidic substance, it is in the form of powder or granules. The particle size is determined to allow gradual release of carbon dioxide over the required period of time.

If necessary, it can be granulated and used. When used to preserve the freshness of food, it is preferable that it is non-toxic and that the alkali forming the salt is non-volatile.
Even cheaper is better. Considering these, calcium carbonate, sodium carbonate, sodium hydrogen carbonate, etc. are particularly preferred.

The hygroscopic substance may be one utilizing chemical adsorption such as calcium chloride, raw coal, magnesium chloride, phosphorus pentoxide, choline chloride, etc., or may be one using chemical adsorption such as natural or synthetic zeolite, activated alumina, silica gel, activated clay, etc. It may also be one that utilizes physical adsorption. The hygroscopic substance may also be in the form of granules or liquid, as long as it can be isolated from carbonic acid-containing substances and acidic substances. However, powder and granules are preferred from the viewpoint of convenience. There is no difference in particle size, but particles with a somewhat larger particle size are often preferable. When used for keeping food fresh, non-toxic materials are preferred, and calcium chloride, magnesium chloride, natural or synthetic zeolite, activated alumina, silica gel, etc. are particularly preferred.

The acidic substance must be solid and more acidic than carbonic acid. The acidic substance may be an organic acid such as powdered acetic acid, ascorbic acid, citric acid, etc., or may be an acid such as boric acid, powdered phosphoric acid, pyrophosphoric acid, metaphosphoric acid, etc. In addition, it may be a salt of a dibasic acid or more. In addition, strongly acidic, medium or weakly acidic cation exchange resins can also be used. This acidic substance needs to be mixed uniformly with the carbonic acid-containing substance, and therefore, at least when mixed with the carbonic acid-containing substance, it is in the form of granules or granules. The particle size is determined so that carbon dioxide gas can be gradually released over a required period of time through a solid phase reaction with a carbonic acid-containing substance. Generally, when the particle size of the carbonic acid-containing substance is large to a certain extent, it is preferable that the acidic substance has a small particle size, whereas when the particle size of the former is small, the particle size of the latter may be coarse to some extent. When used to maintain the freshness of food, it is best to use harmless acidic substances, and from that point of view, organic acids and inorganic acids that can be used as food additives, as well as ion exchange resins, etc. are preferable.↓Acidic substances that have hygroscopic properties In this case, a combination of two types of carbonic acid-containing substances can sufficiently generate CO□ gas.

The carbon dioxide gas releasing agent of the present invention causes a solid phase reaction between a carbonic acid-containing substance and an acidic substance, and therefore, at least both substances are used in a mixed state. The mixing ratio is about 0.1 to 100, usually about 0.1 to 10, of the acidic substance by weight to the carbonic acid-containing substance.

On the other hand, it is preferable to use the hygroscopic substance in the form of powder or granules, and to use it as a mixture of the three in addition to the carbonic acid-containing substance and the acidic substance. The mixing ratio is the weight ratio of hygroscopic substances to carbonic acid-containing substances, which is about 0. It is preferable to use a small amount of hygroscopic substance when the water is in the air, and it is preferable to use a large amount when moisture in the air is continuously supplied in an open system. ``Since the reaction is initiated by mixing, it is preferable to perform mixing immediately before use, and therefore it is preferable to mix at the site of use. Refrigerate the mixture until use if necessary. This mixture can be used by pressurizing it or by adding a suitable binder to pelletize it, if necessary.

The carbon dioxide releasing agent of the present invention can be used to maintain the freshness of livestock products, fruits and vegetables, and the like. In that case, livestock products, fruits and vegetables, etc. are sealed or semi-sealed and the carbon dioxide releasing agent is placed inside them. In that case, the carbon dioxide releasing agent is preferably used in a breathable bag or container. For example, it can be used in paper, cloth, nonwoven fabric, etc.

The amount of carbon dioxide releasing agent to be used is essentially set so that the required carbon dioxide concentration can be maintained. Therefore, the amount used can be reduced as the sealing performance becomes higher. The use of the carbon dioxide gas releasing agent of the present invention is not limited to freshness preservation; for example, it can be mixed with a type of insecticide that releases insecticide into the air to attract mosquitoes and improve insecticidal efficiency.

[Effect]

By applying an acidic substance to a carbonic acid-containing substance in the solid phase, carbon dioxide gas is gradually released, and by coexisting a hygroscopic substance, the humidity in the system is suppressed and the reaction rate to release carbonic acid gas is increased. It is prevented.

〔Example〕

Sodium hydrogen carbonate, calcium chloride, and ascorbic acid were mixed in various weight ratios and placed in a 150 ml beaker (made of glass) in a sealed reaction vessel. Each was sealed with a polyethylene film and aluminum foil, stored at room temperature, and the CO□ gas concentration was measured. Each time the CO□ gas measurement was carried out, the chamber was opened for a short time, and after the air inside was replaced, the chamber was sealed again.

The measurement results are shown in the table below.

NaHCOs: CaC1,: Vitamin C 1 day later 2 days later 3 days later [Effect of the invention] The carbon dioxide gas releasing agent of the present invention can gradually release carbon dioxide gas over a long period of time, and can be used as a freshness-keeping agent for livestock products, fruits and vegetables, and other various products. Can be used for various purposes.

In addition, since it absorbs moisture from the air, it is effective in preventing mold on livestock products and fruits and vegetables.

Patent applicant: Itochu Feed Co., Ltd.

Claims (1)

[Claims] A carbon dioxide release agent made by combining a carbonic acid-containing substance with a hygroscopic substance and an acidic substance.