JPS6170980A - Production of 'koji' variant - Google Patents

Abstract

PURPOSE:A fungus easy to grow in steamed rice is inoculated, then the resultant KOJI is allowed to absorb water, steamed again, further another fungus difficult to grow is inoculated to give a KOJI variant which gives alcoholic beverage with marrow taste, unique flavor and soft acidulated taste within the scope of Japanese SAKE tax law. CONSTITUTION:(A)A fungus easy to grow, e.g., Aspergillus oryzae or Monascus is inoculated to steamed rice to make KOJI (malted rice), which is then allowed to absorb water by 15-30wt% and steamed again. Then, (B) another fungus hard to grow in steamed rice is inoculated to give the objective KOJI. The absorption of water is effected by adding water to KOJI or dipping KOJI in water.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing koji malt using a fungus belonging to the genus Resobus, which is effective for producing alcoholic beverages and foods having a soft, zero taste.

[Conventional technology]

Conventionally, 1^'=H7t;*Koji has been made by inoculating steamed rice with a fungus commonly called Aspergillus oryzae.

One purpose of steaming rice is to sterilize I bacteria attached to raw rice, and the other purpose is to promote the growth of Aspergillus oryzae by gelatinizing rice starch.

However, Rhizopus fungi - on the contrary, C''
L゛It grows easily on raw rice, but it is difficult to grow on steamed rice.

The reason for this is thought to be that rice proteins are denatured by heat, and Rhizopus bacteria have a weak ability to break down these denatured proteins and use them as nutrients, making it difficult to grow.

For this reason, it was previously considered impossible to make koji by inoculating steamed rice with bacteria such as Rhizopus 5, which are difficult to grow in steamed rice.

[Problem that the invention seeks to solve]

Therefore, the inventor conducted an experiment to confirm that the bacteria of the genus Zopus grew well by impregnating the rice with the same type of amino acid during washing and soaking the rice.

However, such processing at the time of washing and soaking the rice violates the definition of sake as stipulated by the Liquor Tax Law, so it cannot be adopted, so koji, which contains the nutrients necessary for growth that nourishes the steamed rice, is prepared using ordinary methods. By first killing this koji mold and using steamed rice as a base of nutrient-rich koji rice, he was able to successfully produce a modified koji in which Rhizopus bacteria were propagated.

[Means to solve the problem]

The present invention involves inoculating steamed rice with bacteria that easily grow in steamed rice, such as Aspergillus oryzae, to produce koji, making this koji absorb 15 to 30% water by weight, and steaming it again to make steamed rice. This method is characterized by producing modified koji by inoculating steamed rice with bacteria such as Rhizopus that are difficult to grow.

+φ This water absorption is done by either adding water to the koji or soaking the koji in water.

In addition, steamed rice is characterized by using Aspergillus oryzae or Monascus bacteria as the bacteria that grow easily, and using Rhizopus or Mucor bacteria as the bacteria that do not easily grow on steamed rice.

To explain this invention using a process diagram, koji made from bacteria that easily grows on steamed rice is produced in the conventional manner, and water is added to it or immersed in water for a certain period of time to give a weight ratio of 15 to 30% (35 to 5% by weight).
When the rice is heated (referred to as steaming) through a rice steamer after absorbing water to 0%), steamed rice with water absorption of about 25 to 42% (45 to 62% moisture) can be obtained.
・Grow on steamed rice (35% water content in koji with Aspergillus oryzae bacteria, for example, Aspergillus oryzae)
55%) Absorb water on cloudy surface. This results in over-humidified steamed rice with a lot of moisture after steaming, which interferes with the process of making koji and makes it difficult to produce high-quality koji.

If the water absorption rate is less than 15% (moisture content 35%), the growth of madder will be delayed, making it more likely to be contaminated with other bacteria, and making it impossible to produce good quality koji.

If koji is directly produced by inoculating uncooked rice with Rhizopus bacteria, contamination with various bacteria is inevitable, making it difficult to produce high-quality koji that is reproducible throughout the year.

In the above process, the reason why the koji that has been painstakingly produced is re-steamed is because different types of bacteria do not grow at the same time, the koji mold is killed by steaming rice, and only the nutrients produced by the koji mold are left behind to allow the growth of new bacteria. It makes things better.

[One example]

(1) When using Aspergillus oryzae koji Steamed rice is inoculated with Aspergillus oryzae bacteria according to the usual method to make koji 1, and this is immersed in water at 15°C for different times to achieve various water absorption rates. Differences in the growth of Rhizobus oryzae were compared and shown in Table 1.

Table 1: Bacterial growth due to differences in water absorption rates Here, koji with a water content of 20% was used and soaked in water for a certain period of time to absorb water to reach the respective water absorption rates. In addition, as a result of processing for 40 minutes at a temperature of about 105℃ for each steamer, 1
Steamed rice had water absorption of 0 to 15%.As a result, growth was most vigorous when water absorption by soaking was 20 to 25%, and the moisture content at that time was 52 to 57%.

Table 2 shows a comparison between the modified koji of the present invention produced in this way and the conventional koji.

Table 2 Enzyme titer of koji When the enzyme titer of koji was measured, there was almost no difference in the total saccharification power. However, the amount of α-amylase in Zopus oryzae bacteria was so low that it could not be measured, but the amount of acidic protease was quite high. Although this bacterium has a weak ability to decompose the denatured proteins necessary for the growth of steamed rice, it grows once using amino acids and veptated as a nutritional source. Care, titer, high, 6. ．． Shire
.

(2) Using Monascus Anka Koji (Red Koji)
,.

In the same manner as in case (1), grow Rhizopus oryzae bacteria.
Table 3 shows a comparison of the growth rates after inoculation.

Table 3: Growth on red malt When comparing red mold with a water content of 15% and red mold with pigment extracted, the red malted rice with pigment extracted grew faster. In both cases, the growth was the same on the 5th day, but as a result of the 0 (3) experiment, the growth was slightly slower than that of the koji made using Aspergillus oryzae. It was found that similar results could be obtained using bacteria of the genus.

(4) Comparing sake made using the koji of the present invention and conventional sake, the taste and aroma are different, but the taste is softer and more sour than conventional sake, and the aroma is more aromatic, compared by gas chromatography. Then they become as different as prisoners.

, [Effects of the Invention] The present invention has succeeded in growing bacteria on steamed rice, which had been considered impossible to produce until now.
As mentioned above, by making ordinary koji and absorbing water, the koji mold is killed leaving only the nutrients produced by the koji mold.
Using this nutritious rice as a base, steamed rice is made again, and this steamed rice is inoculated with bacteria that are difficult to grow in steamed rice to make koji. Unusual koji, which was considered impossible to produce, can now be easily mass-produced.

Since this modified koji satisfies the definition of sake under the Liquor Tax Law, which requires that it be made from rice, water, and koji, it is possible to use this modified koji to produce new sake with a flavor and aroma different from previous sake. become.

For example, the fungus of the genus Zopus produces 7-maric acid as an organic acid, and this 7-maric acid is converted into malic acid by the action of yeast. Therefore, by using the modified koji of the present invention using Rhizopus bacteria, sake and foods with a soft sour taste can be obtained.

In particular, when used in sake, sake with a different aroma from the conventional koji produced by Aspergillus oryzae can be obtained. Similarly, the modified koji of the present invention using the koji of the present invention also exhibits isotropic characteristics that produce a unique aroma with a sense of umami.

[Brief explanation of the drawing]

The reason is the gas chromatography of the present invention and conventional sake. June 30, 1982

Claims (1)

[Scope of Claims] 1. Inoculating steamed rice with bacteria that easily grow in steamed rice, such as Aspergillus oryzae, to produce koji, and making this koji absorb 15 to 30% water by weight, and steaming it again to make steamed rice. A method for producing kari koji, which is characterized by inoculating this steamed rice with bacteria that are difficult to grow in steamed rice, such as Rhizopus spp., to produce kari koji. 2. The method for producing a modified koji according to claim 1, wherein the koji absorbs water by either adding water to the koji or soaking the koji in water. 3. The production of modified koji according to claim 1, in which Aspergillus oryzae or Monascus is used as the bacteria that easily grows in steamed rice, and Rhizopus or Mucor layer bacteria are used as the bacteria that do not easily grow in steamed rice. Law.