JP2934045B2 - Flexible cooling composition and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for cooling cold storage and a method for producing the same. More specifically, flexibility that can be used for local cooling of the head and the like in medical treatment, for maintaining freshness during distribution of fresh foods or beverages such as seafood, meat products, vegetables, etc., and as a cooling agent for coolers and cool storage boxes The present invention relates to a composition for keeping cool and a method for producing the composition.

[0002]

2. Description of the Related Art Conventionally, fish and shellfish have been distributed in boxes together with ice. Since ice is melted water, the cooling time is short, and there is a problem that the melted water comes into contact with a cold-retained material or the like and becomes dirty or water leaks outside. In order to make up for these drawbacks, in recent years, a cooling agent made by filling a cooling container made of a bag or a plastic container of polyethylene or the like with an appropriate liquid or gel-like material and freezing the same has come to be used frequently. Guar gum, polyvinyl alcohol, sodium polyacrylate, polyacrylamide, sodium carboxymethylcellulose (hereinafter abbreviated as CMC),
A high-viscosity aqueous solution of a water-soluble polymer such as starch or a hydrated gel obtained by crosslinking the water-soluble polymer with an inorganic salt such as boric acid or an organic crosslinking agent is used.

[0003] Among them, guar gum has a drawback that it contains proteins and fats as components and becomes a nutrient source of microorganisms, so that it rots when producing or distributing a cooling agent. In addition, these polymer aqueous solutions are usually used at a concentration of 4 to 15%. When the solid content concentration is high, the amount of free water that can be frozen in the system is small, and as a result, the latent heat of melting is reduced. descend. Therefore, there is a drawback that the cool keeping time, which is an important function of the cool keeping agent, is shortened.

As a method of solving these disadvantages, the present inventors have previously proposed using a gel-like material obtained by gelling CMC with a trivalent or higher metal salt as a cooling agent. However, when the CMC gel composition of CMC and trivalent or higher metal ions is frozen, it is extremely hardened and solidified, and the contact area is reduced, so that the local cooling effect is weak.

[0005] Accordingly, there is a need for a flexible cold-retaining composition that is also highly effective in keeping local cold or deformed products.

[0006]

The present inventors have made intensive studies to solve these problems, and as a result, have completed the present invention.

That is, the present invention relates to a carboxymethyl cellulose having an average degree of substitution of carboxymethyl groups per anhydroglucose unit (hereinafter abbreviated as DS) of cellulose of 0.4 to 2.0, and a 1% aqueous solution having a viscosity of 10 to 15000 cps. A hydrogel composition comprising sodium and a salt of a metal having a valence of 3 or more, a flexible cooling composition comprising an additive oil, a surfactant and a freezing point depressant, and an aqueous solution of a CMC having a valence of 3 or more An aqueous solution of a metal salt is mixed to form a gel, and the food oil is added and mixed with stirring to make the gel snow-like,
Then, a surfactant and a freezing point depressant are added, and the mixture is stirred and mixed.

In the present invention, a CMC having a carboxymethyl group DS of 0.4 to 2.0 is used. DS
CMC less than 0.4 is not soluble in water and CM more than 2.0
As for C, only a gel having a low gel strength can be obtained. Also, CMC
Is used in which the viscosity of a 1% aqueous solution is in the range of 10 to 15000 cps. If the viscosity is less than 10 cps, such
CMC has a low degree of polymerization and can only produce gels with low gel strength. Further, when a CMC having a viscosity exceeding 15,000 cps is used, the viscosity is too high and the solid content cannot be reduced to the minimum necessary CMC concentration, and only a gel having a low gel strength can be obtained.

In the present invention, having flexibility means filling a polyethylene bag with a gel-like cooling composition and, when completely frozen, pressing the finger lightly from the outside of the bag and releasing the finger. A state in which traces are temporarily left.

Next, a method for producing the composition for keeping cold according to the present invention will be described in detail.

Having a specific range of DS and viscosity as described above
In a 2 to 7% by weight aqueous solution of CMC, a 3 to 3
When a 10% by weight aqueous solution is mixed, a carboxymethyl group of CMC and a metal ion having a valence of 3 or more are ion-bonded to form a network structure, thereby obtaining a gel. The metal salt used in the present invention may be any salt of a metal having three or more valences, but potassium alum, aluminum sulfate and the like, which are highly safe, are preferred. The amount of the salt of a metal having three or more valences is 1 to 33%, preferably 3 to 11%, in terms of the atomic equivalent number based on the chemical equivalent number of the carboxyl group (-COONa) of CMC. This gel-like substance does not contain substances serving as nutrient sources of microorganisms such as proteins and fats, so that it hardly rots. In addition, since it has a strong structure due to ionic bonds, it shows almost no fluidity and is a stable gel-like material that does not cause a significant decrease in viscosity or water separation due to detachment of cross-linking by light etc. Suitable for Addition of 10 to 50% by weight of an additive oil such as salad oil to the gel-like material thus formed is carried out with stirring and mixing, and the gel-like material is made into a snowy snow-like shape. Next, add 0.5 to 5.
0% by weight and a freezing point depressant such as ethylene glycol
By adding 重量 60% by weight (all based on a gel) and stirring and mixing, a composition for keeping cold, which is flexible even when frozen, is formed.

As the surfactant, it is preferable to use either a nonionic surfactant or an anionic surfactant, and more preferably an anionic surfactant such as sodium alkyl ether sulfate. Further, as the freezing point depressant, salts such as salt and calcium chloride, and polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin can be used.

[0013]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” and “%” are based on weight unless otherwise specified.

Example 1 DS 0.65, 3% aqueous solution of CMC having a viscosity of 442 cps of 1% aqueous solution
10.8 parts of a 5% aqueous solution of potassium alum is added to 100 parts, stirred immediately, and left for 10 to 15 hours to form a complete gel. Next, after adding 30 parts of salad oil, the gel-like material is crushed into a snowy snow-like shape by stirring and mixing. Furthermore, 1 part of sodium alkyl ether sulfate and ethylene glycol 20
The resulting mixture was stirred and mixed to obtain a gel composition, and the gel composition was filled in a polyethylene bag to prepare a cooling agent. This refrigerating agent was frozen at −20 ° C., but had flexibility.

Example 2 DS 0.89, 1% aqueous solution 4% aqueous solution of CMC having a viscosity of 125 cps
12.5 parts of a 5% aqueous solution of potassium alum is added to 100 parts, stirred immediately, and left for 10 to 15 hours to form a complete gel. Next, after adding 35 parts of salad oil, the gel-like material is crushed into a snowy snow-like shape by stirring and mixing. Further, 1.5 parts of sodium lauryl sulfate and 100 parts of ethylene glycol are added, and the mixture is stirred and mixed to obtain a gel composition. Next, the gel composition was filled in a polyethylene bag to prepare a cooling agent. This refrigerating agent was frozen at −40 ° C., but had flexibility.

Comparative Example 1 DS 0.93, 1% aqueous solution 4% aqueous solution of CMC having a viscosity of 121 cps
14 parts of a 5% aqueous solution of potassium alum was added to 100 parts, and the mixture was stirred and mixed to prepare a hydrogel composition. Next, when the gel composition was frozen at −10 to −20 ° C., it became a hard lump.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C09K 5/00 A61F 7/10 A23B 4/06 A23B 7/04 A23L 3/36

Claims (1)

(57) [Claims] 1. An average degree of substitution of carboxymethyl groups per anhydroglucose unit of cellulose is 0.4 to 2.0.
% Aqueous solution of sodium carboxymethylcellulose having a viscosity of 10 to 15000 cps.
A 3 to 10% by weight aqueous solution of the above metal salt is converted to a trivalent or higher metal salt.
Amount of sodium carboxymethylcellulose
1 to 33 atomic equivalents relative to the chemical equivalent of the ruboxyl group.
% To make a gel, and add 10 parts of
Add ~ 50% by weight, stir and mix to make the gel snow-like
0.5 to 5.0% by weight of surfactant and freezing point depression
1 to 60% by weight of the agent (all amounts are based on gel-like material)
To obtain a gel-like composition by stirring and mixing
A method for producing a composition for keeping cold.