JP7745238B2 - Powdered food shelf life enhancer - Google Patents

Description

The present invention relates to a powdered shelf life extender for food that inhibits the growth of yeast and lactic acid bacteria and exhibits excellent bacteriostatic effects.

In recent years, demand for ready-made meals has been rising, with more and more people eating prepared meals purchased from supermarkets and other stores at home. When prepared meals are produced in-house, a large number of ingredients are used to produce a wide variety of prepared meals, which inevitably increases the risk of cross-contamination and leads to an increase in cases of spoilage and food poisoning.

There are many bacteria that cause spoilage, but yeast and lactic acid bacteria are known to be particularly difficult to inhibit. This is thought to be because yeast and lactic acid bacteria grow easily in low pH ranges, making them less susceptible to ingredients such as acetic acid, which improve the shelf life of food.

Therefore, there is a need for shelf-life extenders that inhibit the growth of yeast and lactic acid bacteria and increase the shelf life of food.

Against the background described above, proposals have been made to resolve these issues.

Patent documents 1 and 2 describe food preservatives that combine glycine with sodium acetate or sodium gluconate. However, while glycine is effective against heat-resistant bacteria, its effect in inhibiting the growth of yeast and lactic acid bacteria is not sufficient.

Patent Document 3 proposes a food disinfectant that combines a chelating agent, a surfactant, an organic acid, and a salt of an organic acid. However, because these ingredients are so diverse, some combinations are insufficient in inhibiting the growth of yeast and lactic acid bacteria. Furthermore, this disinfectant requires rapid freezing after application to the food, making it unsuitable for foods that are prone to freezing denaturation.

Patent Document 4 proposes a food shelf life extender containing glycerin fatty acid esters and chalconic acid. However, although glycerin fatty acid esters exhibit high antibacterial activity in in vitro tests, their antibacterial activity is significantly reduced in the presence of food components such as starch and protein, making it difficult to achieve sufficient effectiveness.

Japanese Patent Application Publication No. 57-206371 Japanese Patent Application Laid-Open No. 2000-201660 Japanese Patent Application Laid-Open No. 2003-70451 Japanese Patent Application Laid-Open No. 2019-140974

The object of the present invention is to provide a powdered shelf life extender for food that exhibits minimal reduction in antibacterial activity due to the influence of food ingredients, has a growth inhibitory effect on yeast and lactic acid bacteria, and has an excellent shelf life extension effect.

The inventors discovered that the above problems could be solved by blending sodium acetate with a specific organic acid and/or its acid salt, a specific chelating agent, and a specific emulsifier in specific proportions, and thus completed the present invention.

That is, the present invention provides a powdered shelf life extender for food, which contains, per 100 parts by weight of sodium acetate, 0.2 to 25 parts by weight of an organic acid and/or its acid salt, 2 to 100 parts by weight of a chelating agent having a molecular weight of less than 400, and 2 to 20 parts by weight of a glycerin fatty acid ester, wherein the organic acid and/or its acid salt is not gluconic acid, and the glycerin fatty acid ester has a constituent fatty acid with 10 to 12 carbon atoms.

The powdered shelf life extender for food of the present invention is capable of inhibiting the growth of yeast and lactic acid bacteria even in the presence of food ingredients, and is therefore widely used in meat products, fish paste products, various prepared dishes, and the like.

The sodium acetate used in the powdered shelf life extender for food of the present invention is not particularly limited as long as it can be used in foods. For example, it may be a commercially available food additive, or it may be produced by a known method, such as dehydrating sodium acetate trihydrate. Furthermore, it is preferable to use anhydrous sodium acetate as the sodium acetate.

The sodium acetate content in the powdered shelf life extender for food of the present invention is preferably 40 to 90% by weight, more preferably 45 to 88% by weight, and even more preferably 50 to 85% by weight, based on the total weight of the shelf life extender.

The organic acid and/or its acid salt in the powdered shelf life extender for food of the present invention may be any that can be used in food (with the exception of gluconic acid). Specific examples include acetic acid, fumaric acid, citric acid, glutamic acid, malic acid, lactic acid, succinic acid, adipic acid, phytic acid, monosodium succinate, monosodium fumarate, and monopotassium citrate. Of these, acetic acid is preferred because of its excellent shelf life-enhancing effect. In the present invention, acid salts refer to those that exhibit acidity when dissolved in aqueous solution.

The ratio of organic acid and/or acid salts thereof in the powdered shelf life extender for food of the present invention is 0.2 to 25 parts by weight, preferably 0.3 to 20 parts by weight, more preferably 0.4 to 18 parts by weight, and even more preferably 0.5 to 17.5 parts by weight, per 100 parts by weight of sodium acetate. If the ratio of organic acid and/or acid salts thereof is less than 0.2 parts by weight per 100 parts by weight of sodium acetate, the pH tends to be high and it is difficult to achieve a bacteriostatic effect. If the ratio exceeds 25 parts by weight per 100 parts by weight of sodium acetate, the acidity tends to be strong, and the original flavor of the food tends to be impaired.

The powdered shelf life extender for food of the present invention contains a chelating agent with a molecular weight of less than 400. The molecular weight of the chelating agent is preferably less than 350, and more preferably 170 to 300. If the molecular weight of the chelating agent is 400 or more, the bacteriostatic effect tends to be insufficient.

The type of chelating agent used is not particularly limited as long as it can be added to food, and examples include gluconic acid (molecular weight = 196.16), sodium gluconate (molecular weight = 218.14), potassium gluconate (molecular weight = 234.25), gluconodeltalactone (molecular weight = 178.14), disodium dihydrogen pyrophosphate (molecular weight = 221.94), and trisodium citrate (molecular weight = 258.07). Of these chelating agents, organic acids or their salts are preferred because they have less impact on the taste of food. More specifically, sodium gluconate and gluconodeltalactone are more preferred, with sodium gluconate being even more preferred.

The ratio of the chelating agent in the powdered shelf life extender for foods of the present invention is 2 to 100 parts by weight, more preferably 3 to 70 parts by weight, and even more preferably 3.5 to 60 parts by weight, per 100 parts by weight of sodium acetate. If the ratio of the chelating agent to sodium acetate is outside the above range, the bacteriostatic effect tends to be insufficient.

The powdered shelf life extender for food of the present invention further contains a glycerin fatty acid ester. Any glycerin fatty acid ester can be used as long as the constituent fatty acid is a saturated, straight-chain or branched fatty acid having 10 to 12 carbon atoms. However, monoglycerin fatty acid esters and diglycerin fatty acid esters are preferred because they have little effect on the flavor of food. More specifically, monoglycerin capric acid ester, monoglycerin lauric acid ester, and diglycerin lauric acid ester are preferred, with monoglycerin lauric acid ester and diglycerin lauric acid ester being more preferred, and monoglycerin lauric acid ester being even more preferred.

The ratio of glycerin fatty acid ester in the powdered shelf life extender for food of the present invention is 2 to 20 parts by weight, preferably 2.5 to 18 parts by weight, more preferably 3 to 17 parts by weight, and even more preferably 3.5 to 16 parts by weight, per 100 parts by weight of sodium acetate. If the ratio of glycerin fatty acid ester is less than 2 parts by weight per 100 parts by weight of sodium acetate, the bacteriostatic effect tends to be insufficient, while if it exceeds 20 parts by weight per 100 parts by weight of sodium acetate, the product tends to have a strong acrid taste and impair the original flavor of the food.

The powdered shelf life extender for food of the present invention can be obtained by powdering the raw materials through processes such as stirring, kneading, and heating. The manufacturing method is not particularly limited; all raw materials can be added simultaneously and stirred and kneaded to obtain a powder, or each raw material can be added sequentially and stirred and kneaded to obtain a powder.

The powdered shelf life extender for food of the present invention can also be used in the form of an aqueous solution dissolved in water. The pH of the aqueous solution is preferably 4.5 to 6.8, more preferably 4.8 to 6.3, and even more preferably 5.1 to 5.8. If the pH is less than 4.5, the food tends to have a strong sour taste and lose its original flavor, while if the pH is greater than 6.8, the bacteriostatic effect tends to be insufficient. Note that all pH values are for a 1% by weight aqueous solution.

The method for adding the powdered shelf life extender for food of the present invention to food is not particularly limited, and any of mixing, immersion, and spraying methods may be used, but from the standpoint of workability, mixing it together with the food ingredients is preferred.

The amount of the powdered shelf life extender for food of the present invention to be added can be determined appropriately depending on the target food, but it is generally added so that the proportion relative to the total weight of the food is 0.3 to 3 wt%, more preferably 0.5 to 2 wt%, and even more preferably 0.6 to 1.5 wt%. If the proportion of the powdered shelf life extender for food of the present invention relative to the total weight of the food is less than 0.3 wt%, the bacteriostatic effect tends to be insufficient, and if it exceeds 3 wt%, the food tends to have a strong sour or harsh taste, compromising the original flavor of the food.

The powdered shelf life extender for food of the present invention inhibits the growth of not only general bacteria but also yeast and lactic acid bacteria, thereby achieving an excellent shelf life extension effect.

Yeasts whose growth can be inhibited by the powdered shelf life extender for food of the present invention include Saccharomyces cerevisiae, Candida albicans, Pichia anomala, and Pichia farinosa, but the growth of Saccharomyces cerevisiae is particularly effectively inhibited.

In addition, lactic acid bacteria whose growth can be inhibited by the powdered food shelf life extender of the present invention include Lactobacillus brevis, Lactobacillus rhamnosus, Lactobacillus plantarum, and Leuconostoc mesenteroides, with the growth of Lactobacillus brevis being particularly effectively inhibited.

The powdered shelf life extender for food of the present invention may be used in combination with one or more other ingredients, such as glycine, thiamine lauryl sulfate, sucrose fatty acid ester, egg white lysozyme, licorice oil extract, protamine, and other bacteriostatic substances.

Foods that can use the powdered shelf life extender for foods of the present invention are not particularly limited, and examples include fish paste products such as kamaboko, chikuwa, hanpen, fish ham, and sausage; meat products such as ham, sausage, bacon, hamburger steak, and minced meat balls; fried products such as croquettes, pork cutlets, fried chicken, fried fish, and fried chicken; cooked rice products such as fried rice and takikomi gohan; noodles such as Chinese noodles, pasta, udon, and soba; prepared dishes such as potato salad, gyoza, shumai, tamagoyaki (rolled omelet), simmered dishes, and salad dressings; stuffings for curry bread and Chinese buns, sandwich fillings, and other fillings; creams such as custard cream, whipped cream, and flower paste; confectioneries such as castella, sponge cake, buns, and bean paste; and processed fruit products such as jam.

The powdered shelf life extender for food of the present invention is particularly suitable for extending the shelf life of meat products and prepared foods, among the above foods, in which the proliferation of yeast and lactic acid bacteria is often a problem.

The present invention will be further explained below with reference to examples and comparative examples, but the present invention is not limited to these examples.

In the following examples and comparative examples, the following materials were used.
- Sodium acetate (anhydrous) (Mitsubishi Chemical Corporation)
Acetic acid (manufactured by Nichiwagosei Co., Ltd.)
- Fumaric acid (manufactured by Nippon Shokubai Co., Ltd.)
- Sodium gluconate (Fuso Chemical Co., Ltd.)
Glucono-delta-lactone (Fuso Chemical Co., Ltd.)
- Sodium tetrapolyphosphate (manufactured by Rinkagaku Kogyo Co., Ltd.)
- Sodium hexametaphosphate (manufactured by Taihei Chemical Industry Co., Ltd.)
Disodium dihydrogen pyrophosphate (manufactured by Taihei Chemical Industry Co., Ltd.)
Glycerin fatty acid ester 1 (Poem (registered trademark) M-300, manufactured by Riken Vitamin Co., Ltd.)
Glycerin fatty acid ester 2 (Poem (registered trademark) M-100, manufactured by Riken Vitamin Co., Ltd.)
Sucrose fatty acid ester (Ryoto (registered trademark) Sugar Ester P-1670, manufactured by Mitsubishi Chemical Corporation)
Dextrin (Cluster Dextrin (registered trademark), manufactured by Glico Nutrition Foods Co., Ltd.)

Hamburger steak shelf life test
Examples 1, 2, and 4 to 7, Reference Examples 3 and 8, and Comparative Examples 1 to 8
Powdered shelf life extenders for foods were prepared with the compositions shown in Tables 1 and 2. Hamburg steaks were produced using each of the prepared preparations, and the resulting hamburg steaks were subjected to a storage stability test.

Hamburger steak production: 60 g of ground chicken breast, 29 g of Hamburger Helper (House Foods Corporation), 10 g of water, and 1 g of each preparation (1% by weight based on the total food weight) were placed in a food processor (Panasonic Corporation, MK-K48P) and mixed for 1 minute. 10 g of the prepared mixture was molded into patties, steam-heated for 10 minutes in a steam convection oven (Tanico Corporation, TSCO-4EB), allowed to cool for approximately 1 hour, and then subjected to a storage stability test.

The produced hamburger steaks were placed in sterile bags, inoculated with Lactobacillus brevis NBRC3345 as lactic acid bacteria at approximately 10 CFU/g, and stored at 15°C. Similarly, Saccharomyces cerevisiae NBRC0205 as yeast was inoculated at approximately 10 CFU/g, and stored at 15°C. After 5 days for the lactic acid bacteria and 6 days for the yeast, the viable cell count was measured using the pour plate method on standard agar medium or potato dextrose agar medium, and the effectiveness was evaluated according to the following evaluation criteria. The results are shown in Tables 1 and 2.

[Evaluation criteria]
lactic acid bacteria
◯: The number of viable bacteria after 5 days is less than 10 ⁶ (CFU/g) ×: The number of viable bacteria after 5 days is 10 ⁶ (CFU/g) or more
yeast
◯: The number of viable bacteria after 6 days is less than 10 ⁶ (CFU/g) ×: The number of viable bacteria after 6 days is 10 ⁶ (CFU/g) or more

Sensory evaluation
Example 1 and Comparative Examples 9 to 11
A potato salad was prepared by adding 0.5 g of salt and 64.5 g of boiling water to 23.0 g of commercially available potato flakes (manufactured by Nippon Garlic Co., Ltd.), stirring well, allowing to cool, and then adding 12.0 g of commercially available mayonnaise. Each of the powdered food shelf life extenders of Example 1 and Comparative Examples 9 to 11 shown in Table 3 was added at 1.0 wt % to the total amount of the prepared potato salad. The potato salad obtained was eaten by a panel of 12 people and evaluated for sourness and harshness. The evaluation results, using Example 1 as the evaluation control, are shown in Table 3, based on the following criteria.

[Evaluation criteria for sourness]
○: Less sour than Example 1 △: Same sourness as Example 1 ×: Stronger sourness than Example 1 [Evaluation criteria for bitterness]
○: Less harsh than Example 1 △: Equivalent harshness to Example 1 ×: Stronger harshness than Example 1

Claims (6)

A powdered shelf life extender for food, comprising 0.3 to 17.5 parts by weight of an organic acid and/or its acid salt, 3.5 to 70 parts by weight of a chelating agent having a molecular weight of less than 400, and 3 to 18 parts by weight of a glycerin fatty acid ester, relative to 100 parts by weight of sodium acetate,
the organic acid and/or its acid salt is at least one selected from the group consisting of acetic acid, fumaric acid, and sodium salts thereof;
the chelating agent is sodium gluconate;
The powdered shelf life extender for food, wherein the glycerin fatty acid ester is a monoglycerin fatty acid ester having a constituent fatty acid with 10 to 12 carbon atoms. 2. The powdered shelf life extender for foods according to claim 1 , wherein a pH of a 1 wt% aqueous solution thereof is 4.5 to 6.8. 3. The powdered shelf life extender for food according to claim 1 , which is used to inhibit the growth of yeast and lactic acid bacteria. 4. The powdered shelf life extender for foods according to claim 3 , wherein the yeast is one or more species selected from the group consisting of Saccharomyces cerevisiae, Candida albicans, Pichia anomala, and Pichia farinosa. 4. The powdered shelf life extender for foods according to claim 3 , wherein the lactic acid bacterium is one or more species selected from the group consisting of Lactobacillus brevis, Lactobacillus rhamnosus, Lactobacillus plantarum, and Leuconostoc mesenteroides. A method for improving the shelf life of food, comprising adding the powdered shelf life improver for food according to any one of claims 1 to 5 to food , wherein the powdered shelf life improver for food is added in an amount of 1 to 3% by weight based on the total amount of the food .