JP6456696B2 - Method for improving fermentation characteristics of brewer's yeast in fed-batch culture - Google Patents

Description

  The present invention relates to a habituation technique for improving fermentation characteristics of brewing yeast obtained by fed-batch culture.

  By applying the fed-batch culture method commonly used for culturing baker's yeast to brewer's yeast culture, it is more efficient than batch culture using wort, which is an existing brewer's yeast culture method, and requires wort It is known that it is possible to culture brewery yeast that does not (see Non-Patent Document 1).

  On the other hand, in fed-batch culture of baker's yeast, methods are known in which storage tolerance is improved by extremely restricting sugar supply at the end of the culture and lowering the germination rate while continuing aeration (Non-Patent Document 2 and Non-Patent Document 2). Patent Document 3). In addition, it is known that the glucose tolerance of a yeast cell line can be increased by placing the yeast cell line in an acclimatization process containing a high concentration of glucose (Non-patent Document 4).

Hiroki Fujiwara et al., MBAA Annual Conference 2014 "Development of the Fed-batch Culture of Brewing Yeast" Master Brewers Association of the Americas Gerald Reed et al., Yeast Technology, p.283 A. H. Rose et al., The Yeast, p.387 William D. Gray, Journal of Bacteriology, vol.52, pp.703-709, 1946

  However, when fermenting beer etc. using brewing yeast obtained by fed-batch culture, the sugar consumption rate is slow compared to the brewing yeast collected from the fermentation tank for producing beer etc. There are characteristics that the concentration of acetaldehyde, which is an immature odor component of the finished liquid, is high, and the concentration of acetic acid, which is a sour component of the finished liquid of fermentation, is high. Such a feature is recognized as an unpleasant odor such as a bad fermentation feeling or a sour taste in sensory evaluation, and exhibits an unfavorable flavor as compared with the brewer's yeast recovered from the fermentation tank. Therefore, an object of the present invention is to provide a method for acclimating brewing yeast, which exhibits a preferable flavor with reduced feeling of poor fermentation and acidity.

  The inventors of the present invention have eagerly searched for a means for solving the problem that the sugar consumption rate is low and the acetaldehyde concentration and the acetic acid concentration are high according to the conventional method. As a result, the brewer's yeast cell solution obtained by fed-batch culture is anaerobic. It has been found that by performing a conditioned treatment in the presence of sugar and yeast extract under the conditions, the feeling of poor fermentation and acidity are suppressed, and a favorable flavor is exhibited. The present invention is based on this finding.

That is, according to the present invention, the following inventions are provided.
(1) A method of acclimatizing a brewing yeast comprising incubating a brewing yeast cell solution under anaerobic conditions in the presence of sugar and yeast extract.
(2) The brewer's yeast cell solution is obtained by a fed-batch culture method under an aerobic condition, and the cell concentration of the brewer's yeast cell solution is 3 × 10 ⁸ cells / ml or more (1 ) The habituation method as described in.
(3) The acclimation method according to (1) or (2), wherein the addition amount of sugar is 10 to 25 g / 100 ml and the addition amount of yeast extract is 1 to 4% (w / v).
(4) The incubation temperature condition is within the range where the upper limit is the culture temperature when preparing the brewer's yeast cell solution, and the lower limit is the temperature 2 ° C lower than the fermentation temperature when producing the fermented alcoholic beverage. The acclimatization method according to any one of 1) to (3).
(5) The acclimation method according to any one of (1) to (3), wherein the incubation temperature condition is 10 ° C to 20 ° C.
(6) The acclimation method according to any one of (1) to (5), wherein the incubation time is 16 hours or more.
(7) Brewing yeast acclimated by the acclimation method according to any one of (1) to (6).
(8) A method for producing a brewing yeast suitable for brewing a fermented alcoholic beverage, comprising incubating a brewing yeast cell solution under anaerobic conditions in the presence of sugar and yeast extract.
(9) A method for producing a fermented alcoholic beverage, comprising a step of fermenting a pre-fermentation solution using the brewing yeast of (7).
(10) The production method according to (9), wherein the brewer's yeast is beer yeast, and the produced fermented alcoholic beverage is a beer-taste fermented alcoholic beverage.

  The method for acclimating a brewing yeast obtained by fed-batch culture according to the present invention is advantageous in that it can provide a yeast capable of producing a fermented beverage such as beer that has a poor fermentation feeling and a sour taste and has a preferred flavor. . In addition, it is advantageous in that it enables efficient preparation of brewing yeast, coupled with a fed-batch culture method of brewing yeast.

FIG. 1 shows changes over time in sugar consumption when a fermentation test was carried out using three types of brewing yeasts before acclimation, after acclimation, and continuous yeast. FIG. 2 shows a comparison of the amount of sugar remaining at the end of the test when a fermentation test was performed using two types of brewing yeasts before and after acclimation. FIG. 3 shows a comparison of the amount of acetaldehyde contained at the end of the test when a fermentation test was performed using two types of brewing yeasts before and after acclimation. FIG. 4 shows a comparison of the amount of acetic acid remaining at the end of the test when a fermentation test was performed using two types of brewing yeasts before and after acclimation. FIG. 5 shows changes over time in sugar consumption when a fermentation test was performed using four types of brewing yeasts before and after acclimation (the sugar concentration during the acclimation treatment was changed in three stages). FIG. 6 shows changes over time in sugar consumption when a fermentation test was performed using five types of brewing yeasts before and after acclimation (the yeast extract concentration during acclimation treatment was changed in four stages). FIG. 7 shows fermentation using four types of brewing yeast before acclimation and after acclimation (changed to three modes including sugar alone, yeast extract alone, or both sugar and yeast extract during acclimation treatment). The time-dependent change of sugar consumption at the time of performing a test is shown. FIG. 8 shows changes over time in sugar consumption when a fermentation test was performed using three types of brewing yeasts before and after acclimation (acclimation temperature was changed in two stages). FIG. 9 shows changes over time in sugar consumption when a fermentation test was performed using three types of brewing yeasts before and after acclimation (acclimation time was changed in two stages). FIG. 10 shows the cell concentration at the start of the acclimation treatment in the course of fed-batch culture. FIG. 11 shows four types of samples before acclimation (the cell concentration at the start of the acclimation treatment was changed to two levels) and after acclimation (the cell concentration at the start of the acclimation treatment was changed to two levels before acclimation). The time-dependent change of sugar consumption at the time of performing a fermentation test using brewing yeast is shown. FIG. 12 shows a fermentation test using two types of brewing yeasts before and after acclimation (the types of sugar and yeast extract used in the acclimation treatment were changed and the acclimation temperature was set to 10 ° C.). The time-dependent change of sugar consumption is shown.

Detailed description of the invention

Definitions In the present invention, “brewing yeast” refers to a yeast used in the production of fermented alcoholic beverages and liquid seasonings utilizing fermentation. Various yeasts used for fermentation of a pre-fermentation solution in the production process of each fermented alcoholic beverage are known and can be prepared by the acclimation method of the present invention. Examples of the brewer's yeast include sake yeast, shochu yeast, wine yeast and beer yeast, and can be prepared by the acclimation method of the present invention. “Beer yeast” is a kind of brewer's yeast and refers to a yeast used for producing beer-taste fermented alcoholic beverages such as beer. The brewer's yeast is a top yeast ( Saccharomyces cerevisiae ) or a bottom fermenting yeast ( Saccharomyces pastorianus ) belonging to the genus Saccharomyces , and is a yeast that has been selected and bred based on the ability to produce alcohol.

  In the present invention, “acclimation” means that as a result of moving to a different environment, it gradually becomes adapted to the environment.

Method of acclimatizing brewing yeast The acclimation treatment in the present invention includes incubating a brewing yeast cell solution under anaerobic conditions in the presence of sugar and yeast extract.

  As the brewer's yeast in the present invention, known and commercially available ones can be used. The brewer's yeast is preferably beer yeast.

The brewer's yeast cell solution in the present invention can be prepared by using a known fed-batch culture method under known aerobic conditions. Here, “fed-batch culture” is also called semi-batch culture, and refers to culturing cells while supplying medium components to the culture system. The culture temperature when preparing the brewing yeast is preferably 20 ° C to 30 ° C. The cell concentration of the brewer's yeast cell solution used for the acclimation treatment can be freely set by those skilled in the art, but is preferably at least 3 × 10 ⁸ cells / ml or more, more preferably 9 × 10 ⁸ cells / ml. At the above cell concentration, the expected habituation effect is obtained.

  The anaerobic condition in the present invention can be achieved by stopping aeration to the brewer's yeast cell solution and gently stirring or stopping stirring. Preferably, the brewer's yeast cell solution prepared by the fed-batch culture method is incubated under the conditions of an aeration rate of 0 vvm and a stirring speed of 100 rpm.

  As the sugar in the present invention, saccharides that can be assimilated by yeast, such as glucose, fructose, maltose, and a mixture thereof can be used, and a mixture of glucose and fructose is preferably used. These sugars may be solid or liquid (liquid sugar). According to a preferred embodiment of the present invention, the amount of sugar added is 10-25 g / 100 ml, ie 10-25 g per 100 ml of the incubated liquid. The sugar addition procedure includes both batch addition for adding all necessary amounts at once and divided addition for adding multiple times, but either addition method may be used as long as the above-mentioned sugar addition amount is satisfied. .

  The yeast extract in this invention can utilize a commercially available thing. As yeast extract, those derived from brewer's yeast and those derived from baker's yeast can be preferably used. According to a preferred embodiment of the present invention, the added amount of yeast extract is 1 to 4% (w / v), that is, 1 to 4% (w / v) with respect to the total amount of liquid to be incubated. The yeast extract addition procedure includes both batch addition to add all necessary amounts at once and divided addition to add multiple times, but as long as the above yeast extract addition amount is satisfied, But you can.

  Incubation in the present invention refers to maintaining an object at a constant temperature. In the present invention, the incubation temperature condition (acclimation temperature) is preferably a range in which the upper limit is the culture temperature when preparing the brewer's yeast cell solution and the lower limit is the temperature 2 ° C. lower than the fermentation temperature when producing the fermented alcoholic beverage. More preferably, it is 10 degreeC-20 degreeC.

  In the present invention, the incubation time (acclimation time) can be determined by periodically checking the properties of the yeast being treated. Although specific time is not specifically limited, Preferably it is 16 hours or more, More preferably, it is 22 hours or more. The upper limit of the incubation time is not particularly limited, but is preferably 48 hours.

  The present invention relates to a brewing yeast acclimation method for obtaining a brewing yeast used for fermentation of a pre-fermentation solution in a production process of a fermented alcoholic beverage. The brewing yeast can be, for example, beer yeast, wine yeast or shochu yeast.

  According to the acclimatization method of the present invention, yeast suitable for brewing a fermented alcoholic beverage can be produced. Therefore, according to the other aspect of this invention, the manufacturing method of the brewing yeast suitable for the brewing of a fermented alcoholic beverage including the process of the above-mentioned acclimatization method is provided.

  The brewer's yeast conditioned by the acclimation method of the present invention is suitably used for producing a fermented alcoholic beverage. Therefore, according to the other aspect of this invention, the manufacturing method of a fermented alcoholic beverage which comprises the process of fermenting a pre-fermentation liquid using the brewing yeast conditioned by the acclimation method of this invention is provided. This method preferably further comprises the step of preparing brewer's yeast by the acclimation method of the present invention. Moreover, the fermented alcoholic beverage manufactured by this method also forms one aspect of the present invention. Here, “fermented alcoholic beverage” means liquor, and examples include sake, shochu, mirin, beer-taste fermented alcoholic beverage, fruit liquor such as wine, whiskeys, spirits and liqueurs. In the present invention, the fermented alcoholic beverage is an alcoholic beverage containing alcohol obtained by fermentation with yeast using a carbon source, a nitrogen source, water, and the like as raw materials. A method for producing a fermented alcoholic beverage is well known to those skilled in the art, and can be produced according to a known production method. Fermentation temperature at the time of manufacturing this fermented alcoholic beverage becomes like this. Preferably it is 10-30 degreeC, More preferably, it is 10-20 degreeC.

  According to a preferred embodiment of the present invention, in the above method for producing a fermented alcoholic beverage, the brewer's yeast is a brewer's yeast, and the fermented alcoholic beverage produced is a beer-taste fermented alcoholic beverage. Therefore, according to the other aspect of this invention, the manufacturing method of a beer taste fermented alcoholic beverage which comprises the process of fermenting a pre-fermentation liquid using the brewer's yeast conditioned by the acclimation method of this invention is provided. . The method preferably further comprises the step of preparing brewer's yeast by the acclimation method of the present invention. Moreover, the beer taste fermented alcoholic beverage manufactured by this method also forms one aspect of the present invention. In the present invention, the “beer-taste fermented alcoholic beverage” refers to an alcoholic beverage having a beer flavor, which is a beverage fermented with yeast using a carbon source, a nitrogen source, and water as raw materials. As “beer-taste fermented alcoholic beverages”, beer-taste fermented beverages that do not use wheat and malt as raw materials (for example, beverages classified as “other brewed liquors (foaming) (1)” under the liquor tax law), Examples include beer, malt liquor, and liqueur (for example, beverages classified as “liqueur (foaming) (1)” under the liquor tax law) using malt as a raw material.

  A method for producing a beer-taste fermented alcoholic beverage is well known to those skilled in the art and can be carried out according to a known production method. For example, a beer-taste fermented alcoholic beverage that does not use wheat and malt as raw materials can be produced by fermenting a pre-fermentation solution prepared from at least water and liquid sugar. That is, fermentation is performed by adding the brewer's yeast for fermentation obtained by the acclimation method of the present invention to the pre-fermentation solution (preparation solution) prepared from water and liquid sugar, and the resulting fermentation solution (sake-dried solution). Is stored at a low temperature if desired, and then the yeast is removed by a filtration step, whereby a beer-taste fermented alcoholic beverage can be produced. Moreover, the beer taste fermented alcoholic beverage which uses malt as a raw material can be manufactured by fermenting the pre-fermentation liquid (wort) prepared from water and malt at least. That is, fermenting beer yeast obtained by the acclimation method of the present invention is added to a pre-fermentation solution (wort) prepared from water and malt, and fermentation is performed. If desired, the beer-taste fermented alcoholic beverage can be produced by storing the yeast at a low temperature and then removing the yeast by a filtration step. In any of the production methods, auxiliary materials such as wheat, rice, corn, and starch can be added as a carbon source and a nitrogen source in accordance with regulations of the liquor tax law and the like. Similarly, other additives such as hops, fragrances, coloring agents (caramel), water conditioners, fermentation aids, and the like can be added. The fermentation temperature for producing this beer-taste fermented alcoholic beverage is preferably 10 ° C to 20 ° C.

  The present invention will be specifically described based on the following examples, but the present invention is not limited to these examples.

Example 1: Influence of Fermentation Solution Analyzed Value and Flavor Evaluation with and without Conditioning Treatment (1) Preparation of Brewing Yeast Cell Solution by Fed-batch Culture Initial media and feed solutions were prepared according to Table 1 below. During the culture, the ammonium ion concentration of the medium was maintained at 0.9 g / L or less. Moreover, these culture media were culture media which did not contain any of molasses, wort and aqueous ammonia.

  In addition, the glucose fructose liquid sugar used the grape sugar fructose liquid sugar made from Nippon Food Chemical Co., Ltd., and the yeast extract made from MC Food Specialties was used as baker's yeast extract. Each medium was adjusted to a pH of 4.2 and maintained at a pH during culture using a 25% KOH solution. The initial medium contained 0.82 g / L of ammonium ions.

First, the bottom fermentation yeast was inoculated as the brewing yeast in the initial medium in the jar, and the culture was performed under the conditions of 20 ° C., stirring (800 rpm) and aeration (2.67 vvm). In addition, the fed-batch culture was a continuous fed-batch culture, and was performed while adding a feed solution as a fed-batch substrate solution to the medium so that the addition amount became the maximum amount throughout the culture period as long as ethanol was not generated. That is, during the culture process, the ethanol concentration in the culture solution was maintained at 1.0% by volume or less. The cell concentration 40 hours after the start of the culture reached about 10 ⁹ cells / ml.

(2) Acclimation of brewing yeast To the brewing yeast cell solution obtained in (1), glucose fructose liquid sugar (manufactured by Nippon Food Processing Co., Ltd.) is added so that the cumulative concentration is 20 g / 100 ml, and the final concentration is The baker's yeast extract (MC Food Specialties) was added so that it might become% (W / V). The jar fermenter aeration was stopped, gently agitated, and maintained at 15 ° C. for 22 hours of incubation. Thereafter, the culture supernatant was removed from the yeast cell solution with a centrifuge, and the brewing yeast was recovered.

(3) Fermentation test The fermentation test was performed so that the number of yeast cells was 10 × 10 ⁶ cells / ml with respect to wort, and the temperature was constant at 12 ° C. The brewing yeast to be subjected to the fermentation test was obtained from (1), which was not subjected to the acclimation treatment of (2) with the brewing yeast cell solution obtained in (1) (hereinafter referred to as “before acclimation”). Using three types of brewed yeast cell solution (2) conditioned (hereinafter referred to as “after acclimation”) and recovered from the fermentation tank (hereinafter referred to as “continuous yeast”) A fermentation test was performed.

(4) Analysis of fermentation broth The fermentation broth of the fermentation test of (3) was sampled over time and the sugar content was measured. Moreover, the density | concentration of the acetaldehyde of the fermentation liquid after completion | finish of a fermentation test and an acetic acid was measured.

(5) Sensory evaluation of fermentation broth The sensory evaluation of the fermentation broth after completion of the fermentation test of (3) was performed. As evaluation items for sensory evaluation, two items were set, a poor fermentation feeling and a sour taste. The specific evaluation criteria for each evaluation item are shown below.
a. Unsatisfactory fermentation: A characteristic odor of acetaldehyde, reminiscent of green apples. A: Weak, B: Slightly weak, C: Slightly strong, D: Strong.
b. Sour taste: An off-flavor reminiscent of the stimulating sourness characteristic of acetic acid. A: Weak, B: Slightly weak, C: Slightly strong, D: Strong.
Sensory evaluation was performed by a panel of 3 trained persons.

  In addition, based on the results of these two items, the overall evaluation of the flavor comparison with the continuous yeast recovered from the beer fermentation broth is given in four stages: A: good, B: slightly good, C: slightly bad, D: bad. It was derived by.

(6) Result The result of the analytical test of the fermented liquor obtained by the fermentation test was as FIG. As shown in FIGS. 1 and 2, the fermentation test using the brewed yeast after acclimation has a higher sugar consumption rate than the brewed yeast before the acclimation, and is equivalent to the fermentation test using continuous yeast. there were. Moreover, as shown in FIGS. 3 and 4, in the fermentation test using the brewed yeast after acclimation, the contents of acetaldehyde and acetic acid were low compared to the brewing yeast before acclimation.

The results of sensory evaluation of the fermentation broth were as shown in Table 2 below.

  As shown in Table 2, in the fermentation test using the brewed yeast after acclimation, the feeling of poor fermentation and acidity were suppressed as compared with the brewed yeast before acclimation, and the fermentation test was performed using continuous yeast And almost the same flavor.

  From these facts, it was found that by acclimating the brewing yeast obtained by fed-batch culture, the feeling of poor fermentation and acidity were suppressed, and a preferred flavor almost equivalent to that of continuous yeast was exhibited.

Example 2: Influence of each operating factor on fermentation broth analysis value in acclimation treatment In order to investigate the influence of various operating factors during the acclimation treatment, Preparation of a brewing yeast by fed-batch culture, fermentation test, and analysis of the fermentation broth were performed under the same conditions as in Example 1 except that any of the operating factors of yeast extract addition amount, acclimation temperature, and acclimation time were varied. .

The results were as shown in Tables 3 to 7 and FIGS.

  According to Tables 3-5 and FIGS. 5-7, in the acclimatization process of the brewing yeast obtained by fed-batch culture, when sugar of cumulative concentration 10-25g / 100ml and yeast extract of cumulative concentration 1-4% are added, It was found that the sugar consumption rate was faster and the acetaldehyde and acetic acid contents were lower than the brewing yeast before acclimation.

  According to Table 6 and FIG. 8, in the acclimation treatment of the brewing yeast obtained by fed-batch culture, when the acclimation temperature was set to 15 ° C. or 20 ° C. and incubated, the sugar consumption rate was compared with the brewing yeast before the acclimation. It was found that the content of acetaldehyde and acetic acid was low. Since this acclimatization temperature of 20 ° C. coincides with the temperature condition (20 ° C.) of fed-batch culture when brewing yeast is prepared, it was considered that the acclimatization temperature is preferably set to be equal to or lower than the culture temperature.

  According to Table 7 and FIG. 9, in the acclimation treatment of the brewing yeast obtained by fed-batch culture, when the acclimation time was 16 hours or more, the sugar consumption rate was faster than that of the brewing yeast before acclimation, and acetaldehyde, acetic acid It has been found that the content of is low.

Example 3: Influence of aeration conditions on fermentation broth analysis value in acclimation treatment In order to investigate the influence of aeration conditions during acclimation treatment, sugar addition as shown in Table 8 in (2) brewing yeast acclimation in Example 1 above The amount of the yeast extract added, the acclimation temperature and the acclimation time were set, and the amount of aeration and the stirring speed were changed. Analysis was carried out.

The results were as shown in Table 8.

  According to Table 8, it was found that in the aerobic acclimation conditions, the sugar consumption rate was slower and the acetaldehyde and acetic acid contents were higher than in the anaerobic acclimation conditions. Thereby, it became clear that the acclimation process needs to be performed under anaerobic conditions.

Example 4: Influence of cell concentration on fermentation broth analysis value at start of acclimation In order to examine the influence of cell concentration at the start of acclimation treatment, (1) Preparation of brewing yeast by fed-batch culture in Example 1 above, Brewing yeast was acclimated, fermentation test, and analysis of the fermentation broth were performed under the same conditions as in Example 1 except that the culture broth at an arbitrary number of cells during fed-batch culture was used.

The results were as shown in Table 9, FIG. 10, and FIG.

According to Table 9, FIG. 10, and FIG. 11, in the preparation of brewing yeast by fed-batch culture, at the cell concentration of at least about 3 × 10 ⁸ cells / ml or more, the expected habituation effect (increased sugar consumption rate, alcohol) It was found that a reduced acetaldehyde concentration and a reduced acetic acid concentration were obtained.

Example 5: Effects of sugar and yeast extract added during acclimation treatment and effect of acclimation temperature on fermentation broth analysis value Differences in types of sugar and yeast extract added during acclimation treatment of brewing yeast obtained by fed-batch culture In order to investigate the influence of the acclimation temperature, in the above-mentioned Example 1 (2) brewing yeast acclimation, the yeast extract and liquid sugar to be added are brewer's yeast extract (MC Food Specialties) and malt sugar as the main components. Preparation of brewing yeast by fed-batch culture under the same conditions as in Example 1, fermentation test, analysis of fermented liquid, except that it is changed to maltose liquid sugar (manufactured by Nippon Food Processing Co., Ltd.) Went.

The results were as shown in Table 10 and FIG.

  According to Table 10 and FIG. 12, in the acclimation treatment of brewing yeast obtained by fed-batch culture, the effect of acclimation (increased sugar consumption rate, liquor) Reduced acetaldehyde concentration, reduced alcohol and reduced acetic acid concentration).

  Moreover, according to Table 10 and FIG. 12, in the acclimation process of the brewing yeast obtained by fed-batch culture, when it incubates at 10 degreeC, compared with the brewing yeast before acclimation, sugar consumption rate is quick, and acetaldehyde and acetic acid It was found that the content was low. Since this acclimatization temperature of 10 ° C. is 2 ° C. lower than the temperature condition (12 ° C.) of the fermentation test, the acclimatization temperature exceeds 2 ° C. lower than the fermentation temperature when considered together with the results of Table 6 and FIG. It was considered preferable to set.

Claims (9)

A method of acclimatizing a brewing yeast comprising incubating a brewing yeast cell fluid under anaerobic conditions in the presence of sugar and yeast extract comprising:
The acclimatization method , wherein the brewer's yeast cell liquid is obtained by a fed-batch culture method under an aerobic condition, and the cell concentration of the brewer's yeast cell liquid is 3 × 10 ⁸ cells / ml or more.   The acclimation method according to claim 1, wherein the addition amount of sugar is 10 to 25 g / 100 ml and the addition amount of yeast extract is 1 to 4% (w / v).   The temperature condition of the incubation is within a range in which the upper limit is a culture temperature when preparing a brewer's yeast cell solution and the lower limit is a temperature 2 ° C lower than the fermentation temperature when producing a fermented alcoholic beverage. 2. The acclimation method according to 2.   The acclimation method of Claim 1 or 2 whose temperature conditions of incubation are 10 to 20 degreeC.   The habituation method as described in any one of Claims 1-4 whose incubation time is 16 hours or more.   A brewing yeast acclimated by the acclimation method according to any one of claims 1 to 5. A method for producing a brewing yeast suitable for brewing a fermented alcoholic beverage,
Incubating the brewer's yeast cell fluid under anaerobic conditions in the presence of sugar and yeast extract;
The method wherein the brewer's yeast cell fluid is obtained by a fed-batch culture method under an aerobic condition, and the cell concentration of the brewer's yeast cell fluid is 3 × 10 ⁸ cells / ml or more .   A method for producing a fermented alcoholic beverage, comprising a step of fermenting a pre-fermentation solution using the brewer's yeast according to claim 6.   The production method according to claim 8, wherein the brewer's yeast is brewer's yeast, and the produced fermented alcoholic beverage is a beer-taste fermented alcoholic beverage.

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