JPS59118078A - Preparation of seed malt - Google Patents

Abstract

PURPOSE:To prepare a microbiologically pure seed malt, by culturing a microorganism belonging to Rhizopus genus in a culture medium, and drying the microbial cells obtained by the culture. CONSTITUTION:Microorganism belonging to Rhizopus genus is cultured in an agar culture medium or a liquid culture medium, and the microbial cells obtained by the cultivation are dried by heating or freezing to obtain the objective seed malt.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing seed koji of Rhizopus bacteria.

The rice koji used in sake brewing is also called bara koji, and is made by breeding Aspergillus oryzae on steamed white rice. Anther, ragi, and chang, also called mochi-koji, are made by naturally breeding bacteria of the genus Rhizopus and Mucor in solid flour that has not been steamed.

Mochi koji is made by coarsely crushing uncooked grains, adding water or exudate of bark from roots, and forming them into bricks, dumplings, or rice crackers (1-1), which allows mold and yeast to propagate naturally.

The method for producing rice koji for sake brewing is usually carried out by spraying seed koji on steamed rice and culturing at 1-30°C for about 3 days. In this case, the seed koji to be sprayed is made by culturing Aspergillus oryzae in pure steamed brown rice and heating and drying the cultured brown rice, which is also called bean sprouts and is manufactured and sold by a specialized manufacturer.

However, for Rhizopus genus bacteria, there is no equivalent to the seed koji. The reason for this is that Rhizopus bacteria breed well in unsteamed grains but not in steamed grains, so if Rhizopus bacteria are cultured in unsteamed grains, it will be mycologically pure. The problems include the inability to produce seed koji, and the difficulty in collecting bacterial cells due to poor spore attachment.

As a result of repeated research to produce seed koji of Rhizopus bacteria, the present inventors have found that Rhizopus bacteria are cultured on an agar culture medium, only the bacterial cells are collected after culture, and 1 to 1 are freeze-dried without heat drying. This led to the completion of a method for producing mycologically pure seed koji.

The characteristics of the seed koji production method of the present invention are that Rhizopus bacteria can be cultured in a pure manner, that pure cultured L. bacteria cells can be easily recovered, and that the amount of recovered bacterial cells is 17 times higher than that of natural culture medium. According to the present invention, the dried seed koji is mixed with raw white rice to produce it. Compared to the koji produced using the microorganisms of this method, good results were obtained with almost no dull color.

Next, examples of the present invention will be shown.

Example/Glucose Futa, Pefton/r, 9 mother: r-kiss Oj
2. Potassium monophosphate 0 tag, Magnesium sulfate 0.
．． 2f1 agar 3? A synthetic medium consisting of water/θθ was sterilized under pressure in an autoclave at 770°C for 70 minutes, then poured into a sterilized petri dish with a diameter of 9 cm in a sterile box. After the medium solidified, Rh1zopus javanicus F.
One platinum loop of O3Gugu2 was inoculated from the slant culture, and cultured for 4 days in a 30°C incubator. After culturing, only the bacterial cells were recovered from the medium by heating and drying in a dryer at 1-150°C, 60°C, 70°C, and 705°C for about 5 hours. Table 1 shows the bacterial weight before and after drying.

Next, the dried bacterial cells were used as seed koji to produce koji. After crushing the dried bacterial cells with a vibratory blender, they are suspended in water to be absorbed by raw rice. The rice polishing ratio of the raw white rice used was 75%, and the water absorption ratio was 35%.

After the raw rice uniformly absorbed water, it was cultured for 2 to 3 days in a thermostatic chamber at 3θ°C.

In addition, raw rice/discarded rice was cultured in a petri dish with a diameter of 9 cm,
A petri dish/petri dish of dried bacterial cells was used.

The acidity and enzyme titer of Koji are shown in Table 2.

The analysis was based on the analysis method prescribed by the National Tax Agency.

Example β In the same manner as in Example 1, the bacterial cells cultured in a Petri dish were recovered from the medium and freeze-dried.

Table 3 shows the acidity and enzyme titer of Koji.

Table 3 Enzyme titer (U/2 koji) and acidity Example 3 Rh1 was added to the liquid medium obtained by removing agar from the synthetic medium of Example/.
One platinum loop of Zopus javanicus was inoculated from a slant culture, and cultured with shaking in a thermostat at 30° C. for 1 day. After culturing, the bacterial cells are collected from the culture solution and 6θ
It was heated and dried in a dryer at ℃ for about 5 hours. The bacterial weight after drying is 0. b? //θθmg culture solution.

Dry bacterial cells per white rice/θ02 0. /j? Use 12,
Koji was produced in the same manner as in Example.

The enzyme titer and acidity of Koji are shown in the table.

Table Enzyme titer (U/2 koji) and acidity Patent applicant Fuku, Commissioner of the National Tax Agency 1) Yuki HiroI

Claims (1)

[Claims] A method for producing seed koji, which comprises culturing Rhizopus bacteria in an agar culture medium or liquid culture medium, and after culturing, the bacterial cells are heated and dried or freeze-dried.