JPH09299075A - Production of awamori - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain AWAMORI (Okinawa millet brandy) with mellow taste, rich in higher fatty acid and its ethyl ester each suitable for malt for storage for producing aged sake, by using a variant yeast enhanced in higher fatty acid productivity due to mutation. SOLUTION: First, AWAMORI No.101 yeast belonging to the genus Saccharomyces cerevisiae is inoculated into a medium and proliferated, and the proliferated yeast is sterilely collected and washed and then suspended in a 0.1M phosphate buffer solution (pH7.0) followed by addition of ethyl methanesulfonate and then gently shaking at 30 deg.C to conduct a mutation treatment, and the resultant microbial cell body is cultured in a cerulenin-contg. medium to produce a variant yeast enhanced in higher fatty acid productivity due to mutation. Next, drawn water is blended with koji using the above variant yeast into unrefined AWAMORI, and using the malt, the objective AWAMORI with mellow taste, rich in higher fatty acid and its ester each suitable for malt for storage for producing aged sake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses a mutant yeast having a higher fatty acid-producing ability due to a mutation in a fatty acid biosynthesis system to produce higher fatty acids and higher fatty acid ethyl esters (hereinafter referred to as "higher fatty acids"). ) It relates to a method for producing awamori, which has a high content and a mellow taste and is suitable as a raw sake for storage in the production of old sake.

The higher fatty acids and the like in awamori are one of the important components that determine the taste of awamori, and the quality of liquor varies depending on the content of this component. That is, when the awamori contains a large amount of higher fatty acids, the liquor quality is rich and mellow, and conversely, when it is small, the liquor quality is light.

For awamori, old sake that has been stored and aged has been positioned as a luxury product. The raw sake for storage that is suitable for the storage aging needs to be a "rich brewable sake" that has a high content of higher fatty acids and the like. This is because the sake of sake quality that has a small content of higher fatty acids and the like and has a beautiful sake quality does not easily mature even when stored. In addition, as for the raw sake for mild old sake (increased alcohol with an alcohol content of 25% or less) whose consumption has been increasing recently, the content of higher fatty acids, etc. is maintained in order to maintain its flavor even when water is added. It is necessary that there be many.

The present invention makes it possible to produce awamori, which has a high content of higher fatty acids and is suitable for storage aging, by using a mutant yeast having a higher ability to produce higher fatty acids due to a mutation in the fatty acid biosynthesis system. .

[0005]

2. Description of the Related Art Conventionally, in order to produce awamori having a high content of higher fatty acids and the like, a method of producing higher fatty acids in black koji mold by sufficiently growing the black koji mold in koji making,
Alternatively, a method of increasing the concentration of higher fatty acids and the like by reducing the pumping rate in the mash has been adopted. However, the method of producing Aspergillus niger in koji making is realized at the cost of starch consumption of the raw rice, which leads to a decrease in the amount of pure alcohol and a direct increase in production cost. In addition, the method of lowering the rate of drawing water suppresses the fermentation of yeast, so that the content of mash alcohol is low and the amount of pure alcohol obtained is small, which also increases the manufacturing cost. As described above, in the conventional technique for producing awamori containing a large amount of higher fatty acids and the like, the biggest problem was that the amount of pure alcohol obtained was small.

[0006]

SUMMARY OF THE INVENTION The present invention is in the state of the art, and in order to produce awamori containing a large amount of higher fatty acids and the like without decreasing the pure alcohol yield, a fatty acid biosynthesis system is used. It was focused on using a yeast having a high ability to produce higher fatty acids mutated in.

[0007]

As a yeast having the necessary properties for achieving the above-mentioned object, various naturally used chemical mutagens or physical mutagens were used in addition to natural mutants. It is possible by any acquisition such as an artificial mutant strain. Among these mutant strains, strains that can grow in a medium containing a substance that inhibits the fatty acid biosynthesis system are mutant strains having different fatty acid biosynthesis systems and different in higher fatty acid producing ability. As the substance that inhibits the fatty acid biosynthesis system, any substance can be appropriately used as long as it is a substance that specifically inhibits the fatty acid biosynthesis system. Furthermore, if a mutant yeast having a high fatty acid-producing ability is selected from these mutants, the desired mutant for solving the problem is obtained.

By using the mutant yeast thus obtained to produce awamori according to a conventional method, it is possible to produce awamori with a high content of higher fatty acids without any modification of the equipment and production conditions currently in use. This is one of the major features of the present invention. Hereinafter, the present invention will be described in more detail with reference to Examples.

[0009]

Embodiment 1

[Example of isolation of mutant yeast] Saccharomyces cerevisiae
Awamori No. 101 yeast belonging to e) is inoculated into YPD medium (yeast extract 1%, peptone 1%, glucose 2%) and grown, and then aseptically collected and washed to obtain 0.1M phosphate buffer (pH 7). .0). To this, 0.3 ml of ethyl methane sulfonic acid was added, and the mixture was shaken slowly at 30 ° C. for mutation treatment. After the mutagenesis, the cells were washed once with 10 ml of sodium thiosulfate and twice with 10 ml of sterilized water, and then suspended in 10 ml of sterilized water to cerulenin (an antibiotic that specifically inhibits fatty acid biosynthesis). Final concentration 25μ
M) -containing YPD agar medium (YPD medium plus 2% agar) and cultured at 30 ° C. for 1 week to obtain a mutant strain that is considered to have some mutation in the fatty acid biosynthesis system. .

The obtained mutant strain was subjected to a small preparation test of Awamori mash with 100 g of koji and 150 ml of pumping water.
Several strains with fermentative power comparable to the parent strain Awamori No. 101 yeast were selected, and further, the selected strains were inoculated into YNB medium (yeast nitrogen base 0.67%, glucose 5%), and 2
Pseudo, which has a high substrate specificity for higher fatty acids having 10 or more carbon atoms, was obtained from the culture filtrate cultivated at 5 ° C for 4 days.
Higher fatty acids were quantified by an enzymatic method using an acyl-CoA synthetase derived from the genus monas to obtain a strain having a high ability to produce higher fatty acids.

In the medium, the parent strain Awamori 101 and two strains having high ability to produce higher fatty acids (hereinafter referred to as "strain 1" and "strain 2") were cultured in YNB medium at 25 ° C for 4 days. Higher fatty acid concentration

[Table 1] Shown in As shown in Table 1, both strain 1 and strain 2 produced about 3 times higher fatty acids than the parent strain.

[0012]

[Table 1]

[0013]

Embodiment 2

[Production Example of Awamori Using Mutant Yeast] Strain 1, Strain 2 and Awamori No. 101 were used to calculate the component analysis values before distillation of Awamori mash with 4 Kg of koji and 6 L of pumped water.

[Table 2] In addition,

[Table 3] The analytical values of higher fatty acids and higher fatty acid ethyl esters of sake

[Table 4] Are shown below.

[0014]

[Table 2]

[0015]

[Table 3]

[0016]

[Table 4]

As described above, the awamori produced according to the present invention is comparable to the case of using the parent strain, Awamori No. 101 yeast, in the alcohol content and the pure alcohol yield of the mash before distillation, and it is produced. Higher fatty acid content of sake is about 2 to 3
Higher fatty acid ethyl ester content is about 1.5 times to 2 times
It was twice as many. Also, in the sensory test, the liquor quality was mellow, reflecting the high content of higher fatty acids, etc., and was suitable as a raw sake for storage for the production of old liquor. Furthermore, the obtained sake is 10% alcohol
When the product was water-distilled and sensory-tested, the product of Awamori No. 101 felt watery, while the product using the mutant yeast retained the flavor of Awamori and did not give a thin taste even in fresh sake.

[0018]

EFFECTS OF THE INVENTION By using the mutant yeast of the present invention having a high ability to produce higher fatty acids, awamori suitable for mellow storage sake with a high content of higher fatty acids and the like can be produced without reducing the yield of pure alcohol. It is possible.

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Claims (2)

[Claims] 1. A awamori having a high content of higher fatty acids and higher ethyl ester of higher fatty acids, which is suitable as a raw stock for storage for the production of old liquor, characterized in that a mutant yeast having a higher ability to produce higher fatty acids by mutation is used. Manufacturing method. 2. The method for producing awamori according to claim 1, wherein the mutant yeast having a higher fatty acid-producing ability increased by mutation is obtained by using a cerulenin-containing medium.