JPH11318405A - Preservative for food and food preservation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food preservative originated from natural materials, having high safety and usable without deteriorating the quality of food. SOLUTION: This food preservative contains a DNA extracted from the cell of prokaryotic microorganisms such as Bacillus natto and Escherichia coli and one or more materials selected from organic acids, their salts, amino acids, antibacterial peptides or proteins, polysaccharides comprising sugars, sugar acids and amino sugars, their partial decomposition products, spices, vegetable components, alcohols and bacteriocins.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a preservative for food and a method for preserving food.

[0002]

2. Description of the Related Art The distribution process of foods, store and preservation in stores or at home is a problem that is always required to be solved with the history of human beings, and various physical or chemical methods have been devised as countermeasures therefor. For example,
In addition to freezing, refrigeration, drying, salting, sugar storage, heat sterilization, heat sterilization (bottle and canning), packaging heating, gas phase replacement inside the packaging, pickling, lactic acid fermentation, benzoic acid, sorbic acid, etc. The use of chemical preservatives has been taken as a countermeasure.

[0003] Although the development of food storage and preservation methods has been ongoing since ancient times, the demands on foods themselves change with the times. Although safety is a primary requirement in any age, in recent years there has been a growing interest in health and food, and at the same time, an interest in natural or near-natural foods.

[0004] Such a recent tendency toward foods has a remarkable influence on the method of preserving foods. From a safety perspective, reduce the addition of synthetic preservatives to food as much as possible.From a natural perspective, freezing, refrigeration, drying and salting are not so preferred. Various methods have been developed for various demands for reducing the salt concentration as much as possible.

[0005] Further, a problem with modern foods is that the borders of foods are disappearing, and food materials or foods themselves are being imported from all over the world. This means that, along with food, a variety of microorganisms that attach to or contaminate food are entering the food market widely, and many new food poisoning bacteria such as E. coli O-157: H7 and some The risk of food poisoning due to Salmonella bacteria, botulinum type A or type B bacteria, which has not been detected so far in Japan, has been pointed out.

[0006] A more recent food problem has been the increase in prepared foods, such as salads, sandwiches, fried eggs, custard cream, chicken nuggets, chicken baskets, fries, and the like, and combinations thereof.
The so-called side dishes have come to be marketed with a certain degree of assurance of stability against microorganisms for a certain period of time.

[0007] Further, from the viewpoint of food health, the salt concentration is reduced in all preservable foods. For example, the salt concentration of salted squid was reduced from 10% to 4% to 4%. 12 to 3% of pickles and 4 to 6% of meat products, and 2.5 to 3% of meat products
2%, miso about 13% and 4-8% of dried fish and seafood are decreasing to 0.6-1%. This means that the stability of foods to microorganisms is remarkably reduced, and the foods are not only easily rotted, but also have reduced safety against various food poisoning bacteria.

As a storage and preservation measure for such foods,
First of all, clean the environment in which foods are manufactured, minimize microbial contamination in the production and packaging process of food, use food materials with the lowest possible microbial contamination, perform the manufacturing process through the packaging process. It is customary to take basic measures such as keeping the temperature only low and storing the product at low temperature. However, it is extremely difficult to completely eliminate the number of microorganisms in food raw materials, and if raw meat or seafood is used, at least about 10 ³ / g of microorganisms are present, and Even if there is a heat sterilization step at about 60 to 80 ° C. during the manufacturing process, it is inevitable that heat-resistant bacterial spores remain.

Further, even when food is kept at a low temperature, some bacteria grow well at a low temperature. Some food poisoning bacteria grow at low temperatures, and Yersinia ent
erocolitica, Listeria monocytogenes, Clostridium
Even if stored at a low temperature of about 5 ° C., botulinum type E bacteria and the like grow gradually and produce sufficient amounts of bacteria and toxins to cause food poisoning. Of course, normal psychrotrophs grow over time and spoil food. Food preservation and microbiological safety are not just a matter of food producers and distributors, but are also influenced by the temperature and the passage of time after being brought to the consumer.

[0010]

For these reasons,
Even if microbiological control is sufficiently carried out in the production and distribution processes, it is still necessary for the food itself to have stability or resistance to microorganisms. For this purpose, there is a use of a so-called chemical preservative. However, the use of synthetic preservatives such as benzoic acid, sorbic acid, propionic acid, and parabens has led some consumers to question their safety,
The use of naturally occurring organic acids such as acetic acid and lactic acid or salts thereof, the use of amino acids such as glycine, and the use of protamine which is a milt protein of fish are being attempted. However, although these natural substances have the advantage of safety, from the viewpoint of food preservation, for example, the antibacterial spectrum is narrow, the amount of addition must be large, and the color and unique smell are generated. There was a problem.

[0011] Therefore, the search for substances that are highly safe and that can improve the preservation of food and the safety against microorganisms has been enthusiastically carried out. For example, peptides or proteins produced by lactic acid bacteria, The use of bacteriocin, which has the property of being digested and digested by human digestive enzymes, is being studied (for example, Food Technol)
ogy 164-167, Jan. 1989). However, bacteriocins generally have a narrow range of antibacterial spectrum, and it has been difficult to store foods in a wide range by themselves.

Accordingly, the present invention provides a food preservative which can enhance the preservability of a wider range of foods, is derived from natural products, has high safety, and does not impair the quality of foods. The purpose is to:

[0013]

DISCLOSURE OF THE INVENTION The present invention relates to a DNA extracted from cells of a prokaryotic microorganism, an organic acid and salts thereof,
Selected from the group consisting of amino acids, peptides or proteins having antibacterial properties, polysaccharides composed of sugars, sugar acids and amino sugars and their partially degraded products, spices or plant components, alcohols and bacteriocins It is a food preservative characterized by containing one or more kinds, and a method for preserving food to which they are added.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
In the present invention, the prokaryotic microorganisms include, for example, Bacillus natto, Escherichia coli (E.
coli) and Lactobacillus acidophilus. DNA digested with restriction enzymes
Can be used, but the size of DNA is about 1 k
Base (nucleic acid base) or more is preferred from the viewpoint of the effect of suppressing the growth of microorganisms. Also, from the same point, CpG
Those containing a large amount of dinucleotide sequences are preferred. In addition,
A CpG dinucleotide sequence is a nucleic acid sequence in which C is followed by G
Are arranged, and a sequence connecting these with p (phosphate) is referred to.

As a method for extracting DNA of a prokaryotic microorganism,
For example, Bacillus Natto (IFO3336) is 200m
1 L-broth culture solution (0.1% glucose, 0.5%
% Yeast extract, 1.0% peptone, 0.5
% Sodium chloride, pH 7.2) in a 500 ml Sakaguchi flask at 30 ° C. for 30 hours, and centrifuged (8000 rpm).
m, 10 minutes), washed twice with 0.85% saline, suspended in 40 ml of distilled water, added with 20 mg of lysozyme, allowed to stand at 37 ° C. for 20 minutes, and then cooled to 65 ° C. The temperature was raised to ℃ to destroy the cells, and ethanol cooled to -20 ° C was gradually added, and the insolubilized DNA was rolled up with a glass rod to obtain 500 mg of DNA. The obtained DNA was converted from 70% ethanol to 80
After washing with a gradually increasing concentration of ethanol solution to a solution of 90% ethanol and 90% ethanol, drying under vacuum and dissolving with distilled water to 2 mg / ml yields a highly pure DNA solution. .

[0016] As a food preservative, the DNA extract is usually 10 to 1000 ppm based on the weight of the food to be added.
Preferably 50 to 500 ppm is added. 10p
If it is less than pm, the preservation effect of the food is not sufficient, which is not preferable.

In the food preservative according to the present invention, the D
Along with NA, organic acids and salts thereof, amino acids, peptides or proteins having antibacterial properties, sugars, polysaccharides composed of sugar acids and amino sugars, and partially decomposed products thereof,
When one or two or more compounds selected from the group consisting of spices or plant components, alcohols and bacteriocin are used in combination, the antibacterial spectrum of DNA of prokaryotic microorganisms is further broadened, and the preservation effect is further improved. Can be.

The organic acids and salts thereof used in the present invention include formic acid, acetic acid, propionic acid, valeric acid, lactic acid, citric acid, tartaric acid, malic acid, fumaric acid, oxalic acid, succinic acid, adipic acid, glucone Acid, itaconic acid, sorbic acid, their sodium and potassium salts, vitamin B ₁
Lauryl sulfate; and the like. Among them, acetic acid, lactic acid, citric acid, adipic acid, sorbic acid,
Vitamin B ₁ lauryl sulfate is preferred.

By including these organic acids together, the DNA of the prokaryotic microorganism promotes the penetration of non-dissociated molecules of the organic acids into the cells, thereby changing the pH in the cells,
It is considered that a synergistic effect appears because the cells cause metabolic abnormalities. Organic acids are DNA1 of prokaryotic microorganisms
Is preferably blended at a ratio (weight ratio) of 0.1 to 100.

Examples of the amino acid include glycine, alanine, cystine, threonine, valine, lysine and arginine, and glycine and alanine are particularly preferred. These amino acids cause inhibition of bacterial cell wall synthesis, so that prokaryotic DNA
It is presumed that permeation into the bacterial cell is promoted and its antibacterial action is greatly enhanced. Amino acids are the DNA
It is effective to add 0.1 to 100 (weight ratio) with respect to 1.

Examples of the antimicrobial peptide or protein include protamine and its degradation products, lysozyme and polylysine. Protamine and polylysine bind to the cell membrane of bacterial cells to leak out cell contents, and lysozyme is an enzyme that degrades the cell wall components of Gram-positive bacteria and causes lysis of bacterial cells as a result.
In each case, it is presumed that the entry of prokaryotic microorganism DNA into bacterial cells is enhanced. These peptides or proteins are present in 0.01% of the DNA of prokaryotic microorganisms.
It is preferable to contain at a ratio (weight ratio) of 50 to 50.

Further, examples of polysaccharides composed of sugars, sugar acids and amino sugars and their partial degradation products include pectin, pectin degradation products, oligogalacturonic acid, galacturonic acid, chitosan and chitosan degradation products.
Although there are still many unclear reasons for the inhibitory effect on microorganisms caused by the combined use of these substances, in actual foods, synergistic effects often appear clearly, and therefore, they are usefully used in combination. be able to. Polysaccharides composed of sugars, sugar acids and amino sugars and their partially degraded products are present in 0.0
It is preferable to contain them in a ratio (weight ratio) of 1 to 10.

In the present invention, spices include
Spices having antibacterial properties, such as cinnamon, rosmari, and mace can be used in combination. Further, as the plant component, organic solvent extracts such as alcohol spices, for example, pepper extract, licorice extract, wasabi extract,
Hop extract, Moso bamboo extract; tea tannins, tea catechins, cinnamic acid, ferulic acid, co-acid, hinokitiol and essential oils. The effect of these substances is presumed to be that the phenolic component causes a large damage to the cell membrane of the microorganism, and thus helps the DNA of the prokaryotic microorganism to enter the microbial cells. These spices or plant components are present in an amount of 0.0
It is preferable to contain it in a ratio (weight ratio) of 1 to 100.

Further, alcohols include propylene glycol and ethanol. It is well known that these alcohols inhibit the growth or kill of microorganisms by damaging the membrane tissue of microbial cells, but when used in combination with the DNA of prokaryotic microorganisms of the invention, It has a preserving effect. It is presumed that the reason for this is also to assist the entry of DNA of prokaryotic microorganisms into the microbial cells. In particular, when used in combination with ethanol, a strong bactericidal effect can be expected against Staphylococcus aureus and the like, which are considered to have high ethanol tolerance. It is effective to include alcohols in a ratio (weight ratio) of 0.1 to 1000 with respect to DNA 1 of the prokaryotic microorganism.

In the present invention, there are bacteriocins as compounds which can improve the preservation effect when used in combination with DNA of prokaryotic microorganisms. Bacteriocins are antibacterial proteins or peptides produced by bacteria. All bacteriocins are completely degraded and digested by the human digestive enzymes pepsin, trypsin, chymotrypsin and the like. These have high heat stability, and all
The activity is not lost by heating at 0 ° C. for more than 20 minutes. Furthermore, it basically exhibits antibacterial activity against Gram-positive bacteria, particularly lactic acid bacteria, and also exhibits antibacterial activity against staphylococci, Bacillus subtilis, Clostridium, and Listeria monocytogenes.

Such bacteriocins include, for example, Nisin, Lacticin 48 produced by Lactococcus lactis subsp. Lactis.
1 and Lactostrepcins, Lactoc
deprocosin (Diplococcin) produced by occus lactis subsp. cremoris, Lactococcus lactis subs
those produced by a lactic acid bacterium Lactococcus lactis such as bacteriocin S50 produced by p. diacetilactis; those produced by a lactic acid bacterium genus Pediococcus, called pediocin; La
Lactocin 27 (Lactocin 27) produced by ctobacillus helveticus LP27, Lactobacillus (Reactin) produced by Lactobacillus reuteri, etc. Lactobacillus produced by Lactobacillus (Lactobacillus); ), Such as those produced by the genus Leuconostoc.
and those produced by the genus Lactobacillus Propionibacterium, such as Jenseniin G produced by cterium jensenii P126.

When these bacteriocins are used in combination with the DNA of a prokaryotic microorganism, it is difficult to determine the amount of the bacteriocin depending on the type of bacteriocin.
Is preferably 0.01 to 100 (weight ratio).

In combination with the DNA of the prokaryotic microorganism of the present invention,
As for each substance capable of improving the preservation effect, not only one substance but also several substances may be used in combination. Type, composition,
Depending on the anticipated microorganisms causing contamination or deterioration, pH, water activity, required storage temperature, storage period, etc., two or three or sometimes more substances can be used in combination. For example, when the prokaryotic microorganism DNA of the present invention is used in combination with protamine,
In addition, the addition of acetic acid or lactic acid, and also glycine, can extend the shelf life of many meat products, for example, sausage, ham or Kamaboko, and improve microbial stability. Can be done.

In using the DNA of the prokaryotic microorganism of the present invention in foods, it is necessary to pay attention to the relationship between the salt concentration in the food and the effect, and the effect is large if the salt concentration is relatively high. In such cases, especially in combination with sodium lactate or sodium malate, and several percent or less (in food)
When the alcohols are combined, a great preservation effect can be obtained. In such a case, the effect can be further enhanced by the combined use of lysozyme or polylysine.

Although the DNA of the prokaryotic microorganism of the present invention is unstable to heating in meat slurry, it is generally extremely stable to heat and can withstand heating at 120 ° C. for 10 minutes. Therefore, the number of surviving bacteria can be reduced by heating the food, and the preservative can be effectively enhanced by using the preservative containing DNA of the prokaryotic microorganism of the present invention. Such preservatives include sodium citrate, sodium lactate, polymeric phosphates,
It is preferable to use a sugar or the like in combination.

[0031]

EXAMPLES The effects of the present invention will be more specifically described below with reference to examples. In Examples,% is% by weight unless otherwise specified.

The prokaryotic microorganism D used in the following Examples
NA was manufactured as follows. That is, each of the prokaryotic microorganisms Bacillus natto (IFO3336) and Escherichia coli Escherichia coli K-12 (IFO14410) was added to a 200 ml L-broth culture solution (0.1% glucose, 0.5% yeast extract, 1.0 peptone). , 0.5% salt, pH 7.2) in a 500 ml Sakaguchi flask at 30 ° C. for 30 hours, and centrifuged (800
0 rpm, 10 minutes), wash each of the bacteria twice with 0.85% saline, suspend the bacteria with 40 ml of distilled water, add 20 mg of lysozyme, and add
After leaving it for 65 minutes, the temperature was raised to 65 ° C. to destroy the cells, and ethanol cooled to −20 ° C. was gradually added, and the insolubilized DNA was wound with a glass rod. Was obtained in both cases.

Each DNA was washed with a gradually increasing concentration of an ethanol solution from 70% ethanol to a solution of 80% ethanol and 90% ethanol, dried under vacuum, and adjusted to 2 mg / ml with distilled water. To give a DNA solution.

In the examples, nisin is APLIN & BAR
RETT LTD. Used protamine, pectin decomposed product and chili extract all sold by Asama Kasei Co., Ltd., lysozyme by Eisai Co., Ltd., and polylysine by Chisso Co., Ltd.

Reference Example 1 The antibacterial activity against various bacteria was examined using a 2 mg / ml DNA solution of the above Bacillus natto. That is, the growth of the following test bacteria after culturing at 30 ° C. for 3 days was examined using a tryptic soy medium (pH 6.0). Table 1 shows the results. In the table, +: growth,-: non-growth. The test bacteria are as follows.

1. Bacillus subtilis IAM 1069 2. Staphylococcus aureus FDA 209P 3. 3. Salmonela typhimurium IFO 12529 Escherichia coli IFO 3301 5. Saccharomyces cerevisiae OC-2 6. Hansenula anomala IFO 0141 (p) 7. Pichia membranaefaciens IFO 0128 Lactobacillus plantarum IAM 1041 9. Streptococcus lactis IAM 1249 10. Penicillum decumbens IAM 7260 11. Aspergillus niger

[0037]

[Table 1]

Example 1 1,000 g of minced meat, 300 g of onion, 60 flour
g, the basic composition of a hamburg containing 50 g of water,
Various preservative components (DNA is Bacillus
Natto) was added so as to have the ratio shown in Table 2, and the pH was adjusted to 5.8 with hydrochloric acid or caustic soda. Then, each 30 g was molded, steamed for 25 minutes, and cooled. did. Five samples were prepared for each test plot, stored at 25 ° C., and subjected to a storage test by checking appearance and odor. The test results are shown in the right column of Table 2 as an average value of five storage days.

In the test group to which the preservative of the present invention was added, there was no difference in color, taste, smell, morphology, etc. from the control group before the storage test, and no adverse effect on the quality due to the addition was observed.

[0040]

[Table 2]

Example 2 Salted radish (Taquan) was desalted under running water until the salt content became 3%, and it was seasoned with a seasoning solution having the formulation shown in Table 3 in a refrigerator for 3 days. Next, the preservative (DNA is from Escherichia coli) shown in the left column of Table 4 was added to the seasoning solution of Table 3 at a concentration four times as high as
Takuan 30 seasoned with 100 ml of this
0 g was added and bagged. Various test groups were prepared in the same manner, stored at 20 ° C., and the number of storage days was determined by observing the turbidity of the Taquan solution and swelling of the bag. The results are shown in the right column of Table 4.

[0042]

[Table 3]

[0043]

[Table 4]

Example 3 Alaska pollack SA grade frozen surimi 2.5 kg, salt 75
g, mirin 50 g, soda glutamate 25 g, sugar 2
5 g, potato starch 175 g, and 1 kg of ice water were mixed with a preservative (DNA is from Bacillus Natto) whose composition is shown in the left column of Table 5, and the ratio of each component of the additive to the basic composition was as follows: Various additives were added so that the ratios (% by weight) shown in Table 5 were obtained. After grinding for 30 minutes, the resulting mixture was filled in a vinylidene chloride film (folded diameter: 50 mm) in about 100 g at a time, and dried in hot water at 90 ° C. The kamaboko obtained by heating for a minute
A storage test specimen was prepared together with the preservative-free Kamaboko obtained in the same manner. In the preservation test, 5 casings were stored in a thermostat at 15 ° C. per test section, and the preservability was visually observed to determine the preservative effect. The results are shown in the right column of Table 5.

[0045]

[Table 5]

[0046]

According to the present invention, it is possible to provide a preservative for food which has high preservability and safety of food and which does not impair the quality of food, and a method for preserving such food.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI A23L 3/3526 501 A23L 3/3526 501 3/3562 3/3562

Claims (9)

[Claims] 1. DNA extracted from cells of a prokaryotic microorganism
And organic acids and salts thereof, amino acids, peptides or proteins having antibacterial properties, polysaccharides composed of sugar, sugar acids and amino sugars, and their partially degraded products, spices or plant components, alcohols and bacteriocins A food preservative comprising one or more selected from the group consisting of: 2. DNA extracted from cells of prokaryotic microorganisms
And a food preservative comprising an organic acid and / or a salt thereof. 3. DNA extracted from cells of a prokaryotic microorganism
And an amino acid. 4. DNA extracted from cells of prokaryotic microorganisms
And a food preservative comprising a peptide or protein having antibacterial properties. 5. DNA extracted from cells of a prokaryotic microorganism
And a preservative for food, characterized by containing alcohol. 6. DNA extracted from cells of a prokaryotic microorganism
And a food preservative comprising bacteriocins. 7. The food preservative according to claim 1, wherein the size of the DNA is 1 kbase or more. 8. The food preservative according to claim 1, wherein the DNA contains a large amount of CpG dinucleotide sequence. 9. DNA extracted from cells of a prokaryotic microorganism
And organic acids and salts thereof, amino acids, peptides or proteins having antibacterial properties, polysaccharides composed of sugar, sugar acids and amino sugars, and their partially degraded products, spices or plant components, alcohols and bacteriocins A method for preserving food, comprising adding one or more selected from the group consisting of compounds consisting of: