JPH02167058A - Bacteriostatic agent and starch-containing thermally sterilized food, containing the same and hermetically sealed in container - Google Patents

Abstract

PURPOSE:To obtain a bacteriostatic agent, containing decaglycerol laurate as an active ingredient and capable of exhibiting effective bacteriostatic action on thermostable flat sour bacteria by addition thereof in a small amount so as not to impair flavor of a food even in the coexistence of starch. CONSTITUTION:The objective bacteriostatic agent containing decaglycerol laurate as an active ingredient. For example, in the case of a starch-containing food (normally containing 0.1-5wt.% starch), the content of the decaglycerol laurate in the food may be 0.02wt.%.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to various types of containers formed using paper, resin, metal foil, etc., such as paper packs and laminate containers, or bottles, as storage sealed containers. The present invention relates to a bacteriostatic agent useful for foods (including recreational beverages, etc.) that are filled into cans or the like and stored, distributed, sold, etc. in a heated state if necessary, and foods containing the bacteriostatic agent.

[Prior Art] Various milk drinks and soft drinks have traditionally been sold in sealed containers, and they are also distributed on the market in sealed containers such as cans, bottles, laminated containers, and paper bags. The products of the gods are commercialized as foodstuffs for sale.

Recently, liquid foods such as corn potage soup and shiruko, and new types of beverages such as coffee in sealed containers have been commercialized one after another, and these are heated to around 55℃ using hot plates, hot vendors, etc. It is sold in the condition.

These foods are distributed as products after being filled in sealed containers and sterilized.

However, even in foods that have been sterilized in this way, if they are stored in a heated state for a relatively long period of time, spoilage or deterioration may occur.

As a heat-resistant spore-forming bacterium that causes spoilage and deterioration of food in a heated and sealed state, there is a bacterium called flat sour bacterium that causes so-called flat sour spoilage.

Examples of flat sour bacteria include Bacillus coagulans, a facultative anaerobic spore-forming bacterium.
B. stearothermophilus (B, stearothermo hilous)
Bacteria belonging to the genus Bacillus such as Clostridium thermoaceticum, a thermophilic obligate anaerobic spore-forming bacterium
The presence of bacteria belonging to the genus Clostridium, such as um), has been confirmed.

[Problems to be Solved by the Invention] Various methods such as heat sterilization treatment and addition of various bacteriostatic agents have been applied to prevent flat sour food from spoiling.

For example, for bacteria belonging to the genus Bacillus, 121.
A sufficient effect can be obtained by heat sterilization treatment at 5° C. for about 30 to 40 minutes, which does not alter the quality of the food and is acceptable from a practical standpoint.

However, bacteria belonging to the Clostridium genus, especially Clostridium thermoaceticum, are heat resistant and
Because of the presence of [,] ordinary heat sterilization treatment is not effective enough, and its presence is the main cause of deterioration in heat sterilized foods.

Sucrose valmitate and sucrose stearate are known as bacteriostatic agents for heat-sterilized foods.

However, when using sucrose nysdel palmitate or sucrose stearate as a bacteriostatic agent in foods containing starch, such as potage soup or seaweed,
These must be added in excess to obtain the full effect. However, there is a problem in that excessive addition of these compounds impairs the flavor of the food.

The present invention is useful for heat-sterilized foods in sealed containers that are stored at a temperature as needed, especially starch-containing foods, and is capable of exhibiting sufficient bacteriostatic effects with a small amount of addition without impairing flavor. The purpose of the present invention is to provide a bacteriostatic agent for heat-resistant spore-forming bacteria.

[Means for Solving the Problems] The bacteriostatic agent of the present invention is characterized by containing decaglycerin laurate as an active ingredient.

Decaglycerin lauric acid ester, which is the active ingredient of the bacteriostatic agent of the present invention, contains lauric acid as a fatty acid component, so it can efficiently exert its effect even in the presence of starch, and does not impair the flavor of food. A sufficient effect can be obtained by adding a small amount.

In other words, according to the findings of the present inventors, the decrease in the bacteriostatic activity of sucrose valmitate and sucrose stearate mentioned above in the presence of starch is due to their binding to starch and forming a complex. On the other hand, decaglycerin lauric acid ester, which is the active ingredient of the static agent of the present invention, does not form such a complex with starch, and is highly efficient even in the presence of starch. It can exhibit a good quiet effect.

The type of food to which the bacteriostatic agent of the present invention is applied is not particularly limited, but it is particularly suitable for application to starch-containing foods such as corn potage soup, shiko, and custard-like milk.

The starch contained in these foods may be derived from raw materials or may be used as an additive for imparting thickening properties.

The amount of the bacteriostatic agent of the present invention added to foods varies depending on the line order of the foods. For example, in the case of a starch-containing food (usually containing 0.1 to 5% starch by weight), the lower limit is about 0.02% by weight, which is the content of decaglycerin laurate in the food.

In addition, if the addition of decaglycerin lauric acid ester may impair the flavor of food, the upper limit of the blending ratio of decaglycerin lauric acid ester may be the upper limit within the range where the addition does not impair the flavor of food. The upper limit value varies depending on the type of food, etc., and may be appropriately selected depending on the type of food. Usually, this limit is about 0.2% by weight.

Furthermore, if the starch content in the food is high, the amount added may be increased as appropriate within a range that does not impair the flavor of the food.

The decaglycerin lauric ester used in the bacteriostatic agent of the present invention is obtained by performing an esterification reaction using a material capable of forming a decaglycerin (hydroxyl value of 886 or less) component and a material capable of forming a lauric acid component. A reactant containing decaglycerin laurate, decaglycerin laurate sold by Sakagi Pharmaceutical Co., Ltd. under the trade name SY Glister ML-750, etc. can be used.

Note that decaglycerin fatty acid ester is usually obtained as a mixture of esters having different fatty acid components and esters having different degrees of esterification, so when such a mixture is used in the present invention, lauric acid and monoester are For example, those having a lauric acid content of 60% by weight or more and a monoester content of 30% by weight or more can be used.

Foods containing the bacteriostatic agent of the present invention include foods to which an effective amount of the bacteriostatic agent of the present invention has been added, in paper packs, laminate packs,
It can be obtained by filling a sealed container such as a can or bottle and subjecting it to heat sterilization, if necessary.

The conditions for heat sterilization at this time depend on the type of food.
For example, it may be appropriately selected within a range that does not alter the quality of the food or impair its flavor.

Note that, if necessary, the bacteriostatic agent of the present invention may be added aseptically after heat sterilization of the food.

In addition, when manufacturing foods containing the bacteriostatic agent of the present invention, operations such as mixing raw materials, homogenizing, filling into sealed containers, and sealing the containers are performed using methods generally used in manufacturing foods packed in sealed containers. is available.

For example, when producing canned corn potage soup, edible vegetable oil, sugar, whole milk powder, frozen corn, decaglycerin laurate, starch, etc. are thoroughly mixed in a predetermined ratio and then dissolved in water. , this at 80℃
It can be produced by mixing the mixture under heating for about 10 minutes, filling a can with the resulting mixture, sealing the can, and sterilizing it at a temperature of about 120° C. for 30 minutes.

The amount of decaglycerin lauric acid ester added to the corn potage soup is, for example, 0.02 to 0.2 for Shigekawa.
It is preferable to use the weight percentage, but it may be changed as appropriate depending on the blending ratio of the materials used. For example, if you are concerned about the bitterness associated with the addition of decaglycerin lauric acid ester even if the rod content is 0.2% by weight, you can select an amount of 0.2% by weight or more that does not cause bitterness. .

The canned corn potage soup obtained by the above procedure contains decaglycerin laurate, so
Heat-resistant flat sour bacteria, especially flat sour bacteria including Clostridium thermoaceticum, can be stored at temperatures for long periods of time without causing any deterioration, and the addition of decaglycerin laurate allows for There will be no loss of flavor.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 and Comparative Examples 1 to 3 First, each of the following components was added to 1.02 ml of water, and the pl
+ is adjusted to 7.0 ± 0.1 in a modified TGC medium made by Rasui! ! Add 0.05 ammonium iron (m) citrate to
In addition, a modified TGC medium containing iron (III) ammonium citrate (c-m-
TGC medium) was prepared. In addition, starch was added to the TGC medium to prepare the concentrations shown in Table 1.

Modified TGC medium composition: Peptone soybeptone sucrose sodium chloride agar thioglycol 17.0 g 3.0 horns 6.0 horns 2.5〃 0.77 sodium acid 0.5〃 Old approx. 55-6096; monoester Content approximately 30-40
Lecithin (L25 // Sodium sulfite 0.1) Next, various fatty acid esters were individually added to the prepared cm-T GC medium at various concentrations shown in Table 1, and a total of 12
0 types of media were prepared, and 5+lIn of each medium was dispensed into two test tubes (16 x 160 mm, with screw caps) for each type of medium.

The various fatty acid esters shown in Table 1 include:
The following were used.

Decaglycerin lauric acid ester (Example 1) SY Glister ML-750 (manufactured by Sakamoto Pharmaceutical Co., Ltd.; Lauric acid content: approximately 95 tons)
: Contains monoester (approximately 30 to 40 tons) Decaglycerin stearate (Comparative example 1) SY Glister MS W-750 (manufactured by Sakamoto Pharmaceutical Co., Ltd.; Contains stearic acid) Sucrose valmitate (Comparative example 2) Ryo Ryoto Sugar Ester P-1670 (manufactured by Mitsubishi Kasei Foods Co., Ltd.: Valmitic acid content approximately 70%; monoester content approximately 80%) Sucrose stearate ester (Comparative Example 3) Ryoto Sugar Ester S-1670 (Mitsubishi Kasei Foods Co., Ltd.) Co., Ltd. Nistearic acid content: approx. 70%; monoester content: approx. 75%) Next, add 121" to each medium-containing test tube.
c. After sterilizing by autoclaving for 15 minutes, each medium was treated with Clostridium thermoaceticum spore liquid 0.05 rrrfL (spore count 1.0 x 1).
06 pieces) and then 2ml of liquid paraffin on each medium.
1. After layering, each test tube was sealed with a cap and left at 55°C.

The spores contained in the spore JB solution were activated in advance by treating the spore solution at 98° C. for 15 minutes using a hot water bath.

After 2 weeks, the colored state of each test tube was visually observed, and 11□S produced as the bacteria grew and F in the medium were detected.
The growth of the bacteria was determined using the black discoloration of the culture solution due to FeS produced by the reaction of e.

Judgment criteria are: if black discoloration occurs in the culture solution, "+" indicates "quiet growth";"A" indicates that the culture solution has black discoloration; When no black discoloration occurred on IIi, no growth of bacteria was defined as -.

The results are shown in Table 1.

As is clear from the results in Table 1, a certain bacteriostatic effect was observed in the absence of starch, regardless of the type of decaglycerin and sucrose fatty acid ester. However, in the presence of starch, decaglycerol stearate does not have a bacteriostatic effect even at 2000 ppm, and sucrose palmitate and sucrose stearate do not have a bacteriostatic effect unless they are at high concentrations. Decaglycerin laurate gave a bacteriostatic effect with a smaller addition amount of 1.

Example 2 and Comparative Examples 4 to 5 These components were added to water to the following concentrations, and various fatty acid esters were added to the resulting mixture by stirring and mixing.
Add the various concentrations shown in the table and test tubes (16 x 160 mm
(with screw cap) in 5 ml portions.

Composition: Strawberry bean paste 3% by weight Nerian bean paste 3. Saccharides, etc. 6. Seasonings, etc. 7. The following fatty acid esters were used as shown in Table 2.

Decaglycerin laurate (Example 2) (Same as Example 1) Decaglycerin stearate (Comparative example 4) (Same as Comparative example 1) Hexaglycerin stearate (Comparative example SY-
Glister MS-500 (manufactured by Sakamoto Pharmaceutical Co., Ltd.; stearic acid content approximately 55
~60! (About 30 to 40 tons containing monoester) Next, in each test tube, a spore solution of Clostridium thermoaceticum containing spores that had been activated in advance in the same manner as in Example 1 was added to the solution in the test tube. The spore concentration inside is 9
．． After adding 3xlO3 spores/1n1 and sealing with a screw cap, sterilization was performed by autoclaving at 121°C for 40 minutes.

After sterilization, each test tube was left standing at a temperature of 55°C.

After several months had passed, the pH of each test tube was measured to determine the presence or absence of bacterial growth. The control was the pH of the sample immediately after sterilization. The results are shown in Table 2.

As is clear from the results in Table 2, the comparative examples of decaglycerol stearate and hexaglycerol stearate show a greater pH decrease than the control even when 1000 pptn is added, and a bacteriostatic effect cannot be expected. On the other hand, decaglycerin lauric acid ester of Example 2 had no bacteriostatic effect at 1(If)010m.

Table 2 Note: The values in the table are pH. Example 3 and Comparative Examples 6 to 8 Each component was prepared at the concentrations shown in Table 3. In addition, the various fatty acid esters shown in Table 3 include Fruit'fh Example 1.
And the same ones as in Comparative Examples 1 to 3 were used.

Next, the ':A product was homogenized using a high-pressure homogenizer at 65° C. and 150 kg/cm 2 , and was filled into a 2501 nIt 8-square can.

Furthermore, spore solution 1 [Ij2 (number of spores: 2.4 x lO') of Clostridium thermoaceticum having preactivated spores was added to the inside of each can in the same manner as in Example 1, and the cans were tightly rolled. 121” C140
It was sterilized in an autoclave for a few minutes, and a large number of canned shiruko were produced.

Here, the degree of vacuum inside the can and the pH of the contents of the can of the sampled Qin immediately after the heat sterilization treatment were measured, and the flavor of the can was also examined.

Next, the remaining cans that had been heat sterilized were placed in an incubator at 55°C, and after two weeks, the vacuum level inside the sampled cans and the pH of the contents of the cans were measured. The flavor was tested and a similar test was conducted on the remaining cans after 4 weeks. The results are shown in Table 3.

The method for measuring the degree of vacuum inside the can is as follows.

The samples left and stored at 55° C. were cooled to 20° C., and the degree of vacuum was measured by inserting an in-can vacuum tester (device used: Vacuum Can Tester, manufactured by Japan Canned Food Association) into the can from the bottom of the can.

As is clear from the results in Table 3, the decaglycerol stearate, sucrose palmitate, and sucrose stearate of Comparative Examples 6 to 8 were 0.3
%, all of them deteriorated after 4 weeks.

In contrast, the decaglycerin lauric acid ester of Example 3 of the present invention was 0. The flavor was good with no change at all at the blended concentration of IN.

Additionally, as the contents deteriorate, gas is generated from the contents, which increases the pressure inside the can and lowers the degree of vacuum.

Note that the can vacuum level needle used has an atmospheric pressure of 0 atmospheres and an absolute vacuum level of 76 cm and 11 g, so a larger value indicates a lower atmospheric pressure. That is, atmospheric pressure -70cm1
1g is indicated as 70 by this vacuum degree needle, and the atmospheric pressure is -35cm1
Since 1g is 35, the higher the number, 70, the lower the atmospheric pressure.

In Comparative Examples 6 to 8, a decrease in the degree of vacuum is seen, but in Example 3
In this case, no decrease in the degree of vacuum was observed even after 4 weeks, indicating that no change had occurred at all.

[Effects of the Invention] The sedative of the present invention contains decaglycerin lauric acid ester as an active ingredient, and even in the coexistence of starch,
It exhibits effective bacteriostatic action against heat-resistant flat sour bacteria, especially Clostridium thermoaceticum, when added in small amounts that do not impair the flavor of foods.

Therefore, the food containing the bacteriostatic agent of the present invention has good stability when stored at sufficient temperature by ordinary heat sterilization without fear of denaturation by heat-resistant flat sour bacteria.

Claims (1)

[Scope of Claims] 1) A bacteriostatic agent characterized by containing decaglycerin laurate as an active ingredient. 2) A starch-containing heat-sterilized food packed in a sealed container, characterized by containing decaglycerin laurate.