JPH07274946A - Method for producing malted rice - Google Patents

Abstract

PURPOSE:To enable to obtain the same malted rice as that of Japonica rice, suitable for producing miso (salted and fermented rice), soy sauce, etc., by steaming untreated raw material rice, removing water, treating the steamed rice with a protease, etc., and subsequently subjecting the treated product to a malted rice-producing process under specific conditions. CONSTITUTION:A method for producing a malted rice comprises steaming an untreated raw material rice such as Indica rice, removing excessive water, adding and mixing enzymes containing a protease, an amylase and a cellulase (in an amount of preferably 3000000-12000000 unit per kg of raw rice) to and with the drained raw material rice, treating the raw material rice at 10-40 deg.C for 0.5-3hr, steaming the raw material rice, cooling the steamed raw material rimixing a seed malted rice with the raw material rice, and subsequently subjecting the mixture to a malted rice-producing process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing koji, more particularly to a method for producing koji suitable for brewing miso, soy sauce, rice vinegar, rice shochu, sake, mirin and the like.

[0002]

2. Description of the Related Art With the liberalization of rice, foreign rice has come into circulation. Rice is roughly classified into Indica (long grain) and Japonica (short grain). However, most of the imported rice is long grain type, and few short grain type is suitable for koji making. Compared with short grain type, long grain type has characteristics such as hard surface, different aroma and low water absorption rate even in the state of polished rice. Therefore, there is a problem that it is difficult to make koji by the same method as that for the short grain type.

[0003]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to produce koji using long grain seed rice, and to provide an equivalent to that made from short grain rice.

[0004]

As a result of intensive studies to solve this problem, the present inventor has found that when air steaming and enzyme treatment are used in combination to denature the surface of polished rice, short grain seeds are produced. We have found that rice malt can be made almost unchanged.

The present invention is based on this finding, and the gist thereof is that the first steaming rice step of steaming untreated raw rice, a draining step of removing excess water, and a protease for the raw rice after draining. An enzyme treatment step in which an enzyme containing amylase and cellulase is added and mixed to act at a temperature of 10 to 40 ° C. for 0.5 to 3 hours, a second steamed rice step of steaming raw rice subsequent to the step, and a seed after cooling A method for producing rice koji, which comprises a koji making step of adding and mixing koji to make koji.

The term "air-steaming" as used in the present invention means that the raw material is steamed without any treatment such as washing, soaking and water sprinkling, that is, raw rice which has been polished (sown rice) is not treated. . The apparatus used for the air-steaming treatment is not particularly limited, but a rotary steaming can having a gauge pressure of about 0.3 to 0.5 atm (kg / square centimeter) (for example, an NK can manufactured by Yamazaki Iron Works) is suitable. Air steaming does not require pressurization and may be a normal steam basket. The point is that any device capable of heating the glucomannan layer or the protein layer covering the surface of the polished rice to the extent that it can be thermally denatured may be used.

The time of air steaming is 0.5 to 1 after the steam blows through.
The time is suitable, and the water content of the raw rice is about 2 by this treatment.
Increase to 0% by weight. After air-steaming, leave and cool the raw rice until it reaches 20-30 ° C, add water at 10-20 ° C,
Soak for 5-20 minutes. Alternatively, it may be sprinkled with water and left alone.

After the immersion, the excess water is removed and the enzyme is added to this. The enzyme treatment step of the present invention is mainly used for outer layer destruction of polished rice, water absorption improvement, aroma improvement, gloss enhancement, taste improvement, and enzymes such as cellulase, amylase, protease and pectinase are preferred. A mixture of four types is more preferable. A protease such as papain enzyme destroys the protein layer on the surface of the rice grain and improves water absorption, and thus has the effect of making the koji plump. However, since protease is not effective in improving the handling and stickiness, amylase is added in order to improve workability and make koji with good handling. Good results are obtained by adding cellulase or pectinase to improve the stickiness.

[0009] The amount of protease added is raw rice (water 13
Approximately 16%) 3,000,0 for 1 kilogram
00 to 12,000,000 units (USP method) are preferable, and 4,000,000 to 6,000,000 units are more preferable. Cellulase is also 3 per kilogram
0 to 3,000 units (filter paper disintegration force method) are preferred, and 6
00 to 1,500 units are more preferred. Similarly, amylase is 800-40,000 units per kilogram (J
IS method) is preferable, and 1,600 to 4,000 is better. Similarly, pectinase is 4 for 1 kilogram of raw rice.
0 to 400 units (maceration activation method) are preferred, 1
20-320 are more preferable.

As a method for adding the enzyme, the enzyme preparation is dissolved in warm water (30 to 50 ° C.) of about 3 to 5% by weight with respect to the raw rice, and the solution is added to the raw rice for addition. Mix well and leave for 0.5 to 3 hours. Of course, it is desirable to keep the temperature of the mixed raw materials within the range of 15 to 40 ° C.

After the enzyme treatment, the raw rice is blown again, and then about 0.5.
Steam for ~ 1 hour. The conditions of this steamed rice are the same as those in the first steamed rice process and may be any of a pressure type, a continuous type, a batch type and the like.

After steamed rice is cooled to about 30 ° C., seed koji is added and mixed by a conventional method, and koji is made for about 40 to 50 hours to obtain rice koji.

Hereinafter, the method of the present invention will be described in more detail with reference to Examples, but it goes without saying that the method of the present invention is not limited to these Examples.

[0014]

【Example】

(Example 1) 500 g (g) of polished rice of Indica (produced in Thailand; crushed rice; moisture content 13.4% by weight) was left untreated (raw rice) and steamed for 30 minutes after blow-through. . The water content at this time was 19.5% by weight.

Next, after immersing in 500 ml (ml) of warm water at about 40 ° C. for 15 minutes, the water was drained with a colander. On the other hand, in 25 grams (g) of warm water at about 30 ° C., 500,000 units of papain enzyme as a protease, 100 units of cellulase "Onozuka" 3S (manufactured by Yakult Honsha Co., Ltd.) as cellulase, and Uniase BH-8 (Yakult Co., Ltd.) as amylase. 200 units of the product (manufactured by the head office) and 20 units of Maloteam 2S (manufactured by Yakult Honsha Co., Ltd.) as Pectinaza were added and dissolved. This enzyme solution was mixed with the drained rice and left for 90 minutes under the condition of about 32 ° C.

This rice was steamed for 30 minutes after being blown through, and cooled to about 30.degree. At this time, the water content of steamed rice is 3
It was 8.1% by weight. 200 milligrams of miso seed koji was added and mixed with this, and koji was made for 42 hours under the conditions of a temperature of 35 ° C. and a relative humidity of 95% or more.

The water content at the time of malting was 31.2% by weight. Using this koji, an amazake test was conducted according to Kawamura's simple method for measuring koji-doji (“Miso Technique” No. 1,7,1953; No.5,6.1954). 200g of warm water of about 70 ℃ of 100g of koji was added and saccharified in a hot water bath of 56 ℃ for 1 hour, then filter paper (No.2 fold)
After filtering for 1 hour, the amount of the filtrate and the sugar content were measured. As a result, the sugar content was 16.2 and the filtrate was 157 ml. Therefore, when the product of the sugar content and the filtrate was taken as the total sugar amount, it was 2,543.

(Comparative Example 1) Polished rice of Indica (Thailand; crushed rice; water content 13.4% by weight) 500 g (g) 500 g of water was added to room temperature (about 32 ° C.).
It was left for a time, left on a colander for 90 minutes for draining, and then steamed for 30 minutes. The water content at this time was 38% by weight. Next, an enzyme solution was prepared by adding the same type and proportion of enzyme as in Example 1 above to 50 grams of warm water at about 30 ° C. This enzyme solution was mixed with rice that had been steamed once, and the mixture was allowed to stand for 90 minutes at about 32 ° C.

This raw rice was blown again, steamed for 30 minutes and then cooled to about 30.degree. At this time, the steamed rice had a water content of 39.5% by weight. Add this to the miso seed koji 20
Add and mix 0 milligram, temperature 35 ℃, relative humidity 95
%, And koji was made for 42 hours.

The water content at the time of malting was 31.8% by weight. As a result of an amazake test according to Kawamura's method, the sugar content was 13.
0, the filtrate was 148 ml. Therefore the total sugar is 1,92
It became 4.

(Comparative Example 2) 500 g of milled rice of Japonica (produced in Japan; crushed rice; moisture content of 15.5% by weight) (g) 500 g of water was added and the mixture was heated to about 32 ° C. for 2 hours.
It was left for hours and placed on a colander for 90 minutes for draining.
After that, it was steamed for 30 minutes. The water content at this time was 37.6% by weight.

The steamed rice was cooled to about 30 ° C., 200 mg of miso seed koji was added and mixed, and koji was made for 42 hours at a temperature of 35 ° C. and a relative humidity of 95% or more. The water content at the time of malting was 27.4% by weight. As a result of an amazake test by the method of Kawamura, the sugar content was 20.0 and the filtrate was 111 ml. Therefore, the total sugar amount was 2,220.

(Example 2) Polished rice of Indica (Thailand; crushed rice; moisture content 14.3% by weight) 12 samples of 500 g (g) were left untreated (raw rice) for 30 minutes. I steamed it with Seiro. The water content at this time was 19.8.
% By weight. Next, put each sample in warm water of about 40 ℃.
Excess water was removed after immersion in 00 grams for 15 minutes.

On the other hand, 500 g (g) of warm water at about 40 ° C.
As shown in Table 1, 11 kinds of enzyme solutions of protease, cellulase, amylase and pectinase were prepared. This enzyme solution was mixed with sample steamed rice, and the mixture was allowed to stand at about 32 ° C. for 1 hour to drain water. One sample was a non-addition group, and hot water to which nothing was added was added. Each sample was then steamed again for 30 minutes and cooled to about 30 ° C. To each sample, 200 milligrams of miso seed koji was added and mixed, and koji was made for 42 hours under the conditions of a temperature of 35 ° C. and a relative humidity of 95% or more. The results are shown in Table 1.

[0025]

As described above, in the method of the present invention, the enzyme treatment is performed after the air-steaming, so that the overall treatment time can be shortened. Air-steaming also virtually eliminates the odor peculiar to Indica rice. Furthermore, since the protein layer and the cellulose layer on the surface of the raw white rice are destroyed, there is an advantage that the same malt as Japonica rice can be produced.

[Table 1]

Claims (1)

[Claims] 1. A first steamed rice step of steaming untreated raw rice, a draining step of removing excess water, and an enzyme containing protease, amylase, and cellulase are added to and mixed with the raw rice after draining to a temperature of 10 An enzyme treatment step of operating at -40 ° C for 0.5 to 3 hours, a second steamed rice step of steaming raw rice subsequent to the step, and a koji-making step of adding and mixing seed koji after cooling to make koji. Method for producing rice malt containing.