JPS62186756A - Method for preservation of rice cake from decay - Google Patents

Abstract

PURPOSE:To prevent deterioration and decomposition of rice cake, by adding lactic acid bacteria to rice cake. CONSTITUTION:Rice cake is incorporated with lactic acid bacteria [e.g., Lactobacillus plantarum, Streptococcus thermophilus, Sporolatobacillus, etc., preferably fermentation type lactic acid bacteria] to preserve rice cake from decay.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a technique for preventing tampering and spoilage of rice cakes.

(Prior Art) Mochi is a well-known and commonly used food in Japan, which is produced by steaming sticky rice and kneading the rice. Preventing mochi from being tampered with and spoiled, and stabilizing its quality, is important from the perspective of improving the distribution system and preventing the outbreak of epidemics caused by spoilage.

Up until now, the most commonly used method for preserving rice cakes has been to add quality stabilizers made of food additives to raw rice cakes to prevent the growth of mold and bacteria.

Preventing tampering with packaged rice cakes has been systematized by cleaning the manufacturing environment or using food additives, oxygen absorbers, or packaging materials. Japanese Patent Publication No. 11969), and the combined use of an organic acid, mainly citric acid (Japanese Patent Publication No. 1215/1983), and a sweetener have been disclosed.

The rice cakes are held in a sealed packaging material with high gas barrier performance, and iron-based chest oxygen agents (Japanese Patent Application Laid-Open No. 104867/1982) or a combination of oxygen scavengers and carbon dioxide absorbers (Japanese Patent Application Laid-Open No. 11326/1982) are used.
Publication No. 4) and others disclose a method of suppressing the growth of spoilage bacteria by creating an oxygen-free or carbon dioxide-free state within the packaging material.

(Problems to be Solved by the Invention) However, in these methods, although the preservative effect increases as the amount of quality stabilizers to be added increases, it does not deteriorate the quality of the rice cake or has a negative effect on the human body, etc. This would have led to negative results. Therefore, the present inventors searched for a method that could achieve a preservative effect above a certain level without using the above-mentioned quality stabilizers.

(Means for Solving the Problems) As a result of various studies from the above viewpoint, the present inventors found that lactic acid bacteria, which are generated simultaneously with putrefaction bacteria when rice cakes rot, also inhibit the growth of putrefaction bacteria. I came to discover that
It was discovered that the lactic acid bacteria themselves are effective in preventing spoilage. As Sogo continued his research, he discovered that mochi to which lactic acid bacteria had been added had better stability than mochi to which quality stabilizers had been added, and was better able to prevent spoilage. Although the pl+ of the rice cake decreased slightly due to the proliferation of lactic acid bacteria, it was confirmed that no sourness was felt at all and there was no problem in terms of taste, leading to the completion of the present invention.

The gist of the present invention is to add lactic acid bacteria to rice cake.

As the lactic acid bacteria, any type of lactic acid bacteria can be used as long as it exhibits the effects of the present invention. As the lactic acid bacteria according to the present invention, for example, Lactobacillus plnnLnr
llm), Streptococcus thermophilus (
SLrepLococcus tbermophilu
s), Sporolactobacillus
bacillus), etc. In carrying out the present invention, milk f'rJ 1. Of these, these homofermentative lactic acid bacteria are preferred.

If you want to add these lactic acid bacteria to mochi, you should knead it into the rice cake before adding it to the rice cake.
After rj+ raising and cooling, it can be added to the surface of the rice cake using a method such as injection 7i.

In the case of raw cut rice cakes, the present invention can be carried out by spraying or dipping them in a culture solution of lactic acid bacteria before packaging.

(Example) The present invention will be described in more detail with reference to Examples below.

Example 1 8 kg of sticky rice was soaked in water for 24 hours (9.6 kr),
1.2 kg (10 feet) of water-absorbed rice was steamed using an automatic rice cake pounder (Model FC153 to Toshiba) with 310 ml of water in the bottom boiler. This steamed rice contains lactic acid (5x
109 ccll/g) 1.5g and Bacillus sub
After culturing 1 is PCI-219 strain in 1 trial 5 agar slant medium at 30°C for 48 hours, leave it at room temperature for 2 weeks to form spores, and incubate the spores in sterile water with 73 samples (1
,6X107spores/ml)) 1ml
and 15 g of lactose were added and stirred up for 9 minutes. Finished OJf (approximately 1.5 kg) was filled into a Talehalon casing with a folded diameter of 10 cm, heated at 85° C. for 1 minute, and then cooled to give a finished product.

The above casing mochi was stored at 30°C, and the pH, bacterial count,
Changes in microbial location were tested.

Furthermore, the casing was removed aseptically, cut lengthwise, placed in a sterile petri dish, and stored at room temperature and 30°C to observe the occurrence of white spots and red spots.

The contents of the casing mochi sample are as follows.

For each sample, Bacillus subtilis spores were 1.1×1
0' cell/g, lactose contains 1,0%6.

Commercially available product N is a quality stabilizer °ζ, which is a product that combines glycine and an organic acid.

■ is Lactobacillus plantarum
) (IlanSOn Company II<J.

LACTO-START 03° and below), ■ is Streptococcus thermophilus (S Lrep L
ococcus Lhcrmopl+1lus), and ■ is Sporolactobacillus (Sporolactobacillus).
cillus) (manufactured by Sankyo Co., Ltd., Lafrys S. The same applies hereinafter), respectively.

Changes in pH, number of viable bacteria, and microbial prevalence during storage are shown in Table 1. In addition, the observation results of the external appearance (in a petri dish) during storage of ω at room temperature (20 to 25°C) are shown in Table 2.

(See next page) In Table 1, the units of viable bacteria count are XIO' CPU/g,
In the microflora, ■ represents Bacillus subtilis, and ■ represents Sporolactobacillus.

Table 2 shows the status of spot occurrence (-: No occurrence observed. ±: Slight occurrence. +: Occurrence observed. +1-:
large outbreak). The numbers in the table represent the number of days that have passed. Δ, B, and D have white spots, and the entire mochi has become reddish. In addition, black spots were observed in C and E.

In sample E, there was little variation in pH, and no microflora other than Bacillus subtilis was observed.

Lactobacillus plantarum and Streptococcus thermophilus, which have relatively strong heat resistance, were selected, but it is thought that they could not withstand the temperature at which the rice cake was finished and died.

Furthermore, by comparing Δ, B, and D with C and E, it can be seen that the Bacillus subtilis inhibiting effect of commercial product N is not so recognized.

The modified form of the rice cake surface of Bacillus subtilis is commercially available product N.
In the case of the commercially available N-free sample, it is observed as a common white spot, but in the sample with the commercially available N added, it appears as a blackish brown spot.

When sporolactobacillus was added alone, the number of sporolactobacilli that were detected by T and Q organisms increased, and the pl+ of the rice cake decreased accordingly, and eventually only sporolactobacillus remained.

Increase in Bacillus subtilis due to the antagonistic action of lactic acid bacteria (
1 was suppressed, and it was clear that the occurrence of spots was suppressed.

Looking at the results for sample G, it appears that commercial product N suppresses the growth of both Lactobacillus subI-1 and Bacillus subtilis, but its antagonistic effect on the growth of Sporolactobacillus is not sufficiently strong. However, the combined use of Sporolactobacillus and commercial product N has produced rather poor results. It was found that the addition of Sporolactobacillus alone had better storage stability.

When adding Lactobacillus plantarum, Strebuticus thermophilus, etc., a method such as spraying a bacterial solution on the surface of the rice cake after cooling may be adopted, taking into account its heat resistance.

Example 2 A casing rice cake was produced in the same manner as in Example 1. Instead of Bacillus subtilis in Example 1, Bacillus licheniformis was used as the spoilage bacterium.
Lus! icl+eniformis) IFO-1
2107 and Bacillus cereus
cereus) OUT-8032 was used. The spore solution was prepared by culturing the same strain on a standard agar slant medium at 30°C for 48 hours, leaving it at room temperature for 2 weeks to form spores, and making the spores turbid (Bacillus licheniformis 3) in sterile water.
．． I X 10' spores/ml, Bacillus cereus 2.2
I was bored.

■ in the spore fluid represents Bacillus licheniformis, and ■ represents Bacillus cereus. iQ rank is cell/g.

■ of lactic acid bacteria represents Sporolactobacillus. The unit is c
ell/g. The stabilizer is a combination of glycine and an organic acid.

The casing rice cakes were stored at 30°C, and changes in pl+, bacterial count, and microflora are shown in Table 3. In addition, aseptically remove the gauging, cut it lengthwise, place it in a sterile petri dish, and keep it at room temperature for 30 minutes.
The samples were stored at 0°C and the appearance of bacillus spots was observed, and the results are shown in Table 4.

(See next page below) In Table 3, the unit of the number of viable bacteria is X104C/g, and in the microbial flora, ■ represents Sporolactobacillus, ■ represents Bacillus licheniformis, and ■ represents Bacillus cereus.

Table 4 shows the occurrence of white spots.

The numbers in the table represent the number of days that have passed. All samples were stored at 30°C. The snake was not used for experiments.

When Bacillus licheniformis is added alone, 9[
Spots appeared from around the first eye. However, when Bacillus licheniformis and Sporolactobacillus were added together, very few Bacillus licheniformis bacteria were detected and no spots were observed.

The antiproliferative effect of Sporolactobacillus on Bacillus licheniformis is evident.

It was also found that the results for Bacillus cereus were exactly the same as for Bacillus ligeniformis.

In the case of rice cakes containing only Sporolactobacillus,
Although the number of viable bacteria itself gradually decreases with storage, the pH steadily decreases. It is clear that lactic acid production is occurring due to the active metabolism of Sporolactobacillus. It can be considered that the growth of Bacillus is suppressed by this lactic acid and other produced peroxides (1202, etc.).

Example 3 A casing rice cake was produced in the same manner as in Example 1. Bacillus subtilis as a spoilage bacterium CI-21
9, Bacillus licheniormis IFO-12107, and Bacillus cereus OU i'-8032.

1211. The spore solution was prepared by culturing the same strain on a standard agar slant medium for 30°C for 148 hours, leaving it at room temperature for 2 weeks to form spores, and suspending the spores in sterile water (
Bacillus subtilis 2.5X10' 5pores/
ml, Bacillus riunibuormis 2.3X10fus
pores 1.2XlO' 5pores/ml
), I was very happy with it for one lap.

iJi! Add the designated spoilage bacteria and lactose to each sample and make casing mochi! Ii! ! L: After cooling and hardening, it was sliced aseptically into cut rice cakes. Next, sample 13, l), cut β of F
Lactobacillus branfrum (Lac tobac
I l I usplanLarum) bacterial suspension (
e. oxiov ccll/ml) for 30 seconds, and then air-dried aseptically.

■ in the spore fluid represents Bacillus subtilis, ■ represents Bacillus licheniformis, and ■ represents Bacillus cereus. The unit is cell/g. Lactic acid bacteria■ is Lactobacillus
Represents Branflum.

The sample cut rice cakes were placed in a sterile petri dish and stored at 30° C., and the occurrence of white spots was observed as shown in Table 5.

(Next page below) Table 5 Table 5 shows the occurrence of white spots.

The numbers in the table represent elapsed time. Specimens A, C, and E, which were not subjected to the Lactobacillus plantarum solution immersion treatment, developed white spots due to their respective decomposing bacteria, Bacillus subtilis, Bacillus licheniformis, and Bacillus cereus. On the other hand, samples B, D, and F, which were subjected to the immersion treatment, had no white spots at all, and the taste remained normal over a long period of time. It is a fact that such a soaking treatment method can also prevent deterioration of the rice cake.

Claims (1)

[Claims] A method of preserving rice cake characterized by adding lactic acid bacteria.