JP7212614B2 - New baker's yeast - Google Patents

Description

NPMD NITE BP-02461 NPMD NITE BP-02462 NPMD NITE BP-02463 NPMD NITE BP-02464

TECHNICAL FIELD The present invention relates to novel baker's yeast, bread dough containing the baker's yeast, bread obtained by baking the bread dough, and a method for producing baker's yeast.

In the bread market, breads are actively differentiated by their characteristic flavor and texture. is being considered for improvement. There are various variations of fermented seeds, such as sake seeds and old noodle seeds produced by ethanol fermentation, and sour seeds produced by lactic acid fermentation. By using these fermented seeds as raw materials for bread making, it is possible to impart a characteristic flavor to bread.

However, if these fermenting seeds are added to the bread dough before primary fermentation or secondary fermentation, the fermenting seeds bring ethanol into the bread dough, and the ethanol inhibits fermentation by baker's yeast (carbon dioxide gas generation). was there. This problem of fermentation inhibition due to ethanol occurs remarkably when the ethanol concentration in the dough is 7000 ppm or more. For this reason, if a certain amount or more of fermented seeds containing ethanol is added to bread dough, the bread dough will not rise to the desired volume and the bread volume will be insufficient. time) is longer than usual, and if the amount of baker's yeast added is increased, the bread will have an excessive yeast odor and the balance of the preferred flavor will be impaired. It has been difficult to mix a sufficient amount of fermented seeds into bread dough to efficiently produce soft bread while retaining the flavor derived from the fermented seeds.

Patent Literature 1 discloses that sake seeds produced by fermenting koji, alcohol, and sake lees have high fermenting power and can impart good volume and sake-like flavor to bread. However, neither description nor suggestion is made about baker's yeast having high fermentative power under high ethanol conditions.

JP 2013-153663 A

The object of the present invention is to provide bread obtained by blending fermented seeds containing ethanol, fermenting and baking without extending the proofing time during bread making and lacking the volume of bread, and having a strong and soft flavor derived from fermented seeds. To provide baker's yeast capable of making bread, bread dough containing the yeast, bread obtained by baking the bread dough, and a method for producing baker's yeast.

As a result of intensive research conducted by the present inventors in order to solve the above problems, the amount of gas generated is greater than that of conventional strains in each of medium-sugar dough, high-sugar dough, and ultra-high-sugar dough containing high-concentration ethanol. When the baker's yeast indicated above is used, it is possible to obtain soft bread with a strong flavor derived from the fermented seeds without extending the proofing time at the time of bread making or lacking the volume of the bread mixed with the fermented seeds containing ethanol. The discovery led to the completion of the present invention.

That is, the first aspect of the present invention is formulation 1 (strong flour: 100 parts by weight, white sugar: 15 parts by weight, salt: 1.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight, water: 58 parts by weight, ethanol (99.5% (w/w): 1.82 parts by weight), condition 1 (mix for 3 minutes to obtain a dough, then ferment the dough at 38 ° C. for 1 hour) The amount of gas generated per 50 g of the dough is 180 ml or more, and formulation 2 (strong flour: 100 parts by weight, white sugar: 30 parts by weight, salt: 0.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight parts, water: 52 parts by weight, ethanol (99.5% (w / w)): 1.90 parts by weight), the amount of gas generated per 50 g of the fabric prepared under condition 1 is 130 ml or more, and formulation 3 ( Strong flour: 100 parts by weight, white sugar: 40 parts by weight, salt: 0.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight, water: 47 parts by weight, ethanol (99.5% (w /w)): 1.94 parts by weight), and a baker's yeast characterized by generating 70 ml or more of gas per 50 g of the dough prepared under Condition 1. According to a preferred embodiment, the baker's yeast is used for bread dough having an ethanol concentration of 7000 ppm or more.

The second of the present invention is Saccharomyces cerevisiae KCY1278 (accession number: NITE BP-02462), Saccharomyces cerevisiae KCY1279 (accession number: NITE BP-02463), or Saccharomyces cerevisiae KCY1280 (accession number: NITE BP-02464). about baker's yeast. In addition, the baker's yeast is cross-breeding, mutagenized, or cell-fused baker's yeast, and the amount of gas generated per 50 g of the dough produced under Formulation 1, Condition 1 is 180 ml or more, and produced under Formulation 2, Condition 1. It also relates to baker's yeast that generates 130 ml or more of gas per 50 g of the dough prepared according to Formulation 3, Condition 1 and generates 70 ml or more of gas per 50 g of the dough.

A third aspect of the present invention relates to bread dough containing the baker's yeast. According to a preferred embodiment, the bread dough has an ethanol concentration of 7000 ppm or higher.

The fourth aspect of the present invention relates to bread prepared by heating and cooking the bread dough.

The fifth aspect of the present invention relates to a baker's yeast screening method comprising the following steps. Formulation 1, the amount of gas generated per 50 g of the dough prepared under Condition 1 is 180 ml or more, Formulation 2, the amount of gas generated per 50 g of the dough prepared under Condition 1 is 130 ml or more, and Formulation 3, Condition 1. Baker's yeast (polyploid) belonging to Saccharomyces cerevisiae is selected using as an indicator that the amount of gas generated per 50 g of dough is 70 ml or more.

The sixth aspect of the present invention is a method for producing baker's yeast, comprising a step of crossing baker's yeast to obtain a plurality of hybrid strains, and selecting among the hybrid strains of the plurality of strains according to the following indicators: selecting baker's yeast. Formulation 1, the amount of gas generated per 50 g of the dough prepared under Condition 1 is 180 ml or more, Formulation 2, the amount of gas generated per 50 g of the dough prepared under Condition 1 is 130 ml or more, and Formulation 3, Condition 1. The amount of gas generated per 50 g of dough should be 70 ml or more.

According to the present invention, bread obtained by blending fermented seeds containing ethanol, fermented and baked does not extend the proofing time at the time of bread making or lacks the bread volume, and the flavor derived from the fermented seeds is strong and soft. It is possible to provide baker's yeast capable of making bread, bread dough containing the yeast, bread obtained by baking the bread dough, and a method for producing baker's yeast.

In addition, the baker's yeast of the present invention exhibits high fermentation power in each of medium-sugar dough, high-sugar dough, and ultra-high-sugar dough, and can efficiently produce large-volume, soft bread from each dough. In particular, the baker's yeast of the present invention makes it possible to efficiently produce large-volume, soft bread by additionally adding the yeast of the present invention to sponge dough after fermentation containing a high concentration of ethanol.

The present invention will be described in more detail below.

The baker's yeast of the present invention has a gas generation amount of 180 ml or more per 50 g of the dough produced under the conditions 1 and the formulation 1 shown in Table 1, and the gas per 50 g of the dough produced according to the formulation 2 and the conditions 1 shown in Table 1. The amount of gas generated is 130 ml or more, and the amount of gas generated per 50 g of the dough produced according to Formulation 3 and Condition 1 shown in Table 1 is 70 ml or more. Formulations 1-3 all contain ethanol at a high concentration of 10000 ppm (w/w). No baker's yeast that exhibits high fermentation power in dough containing such a high concentration of ethanol has been known, and the baker's yeast of the present invention is novel.

The baker's yeast of the present invention may be a naturally occurring yeast as long as it satisfies the requirements for the amount of gas generated. Yeast is more preferred. The baker's yeast of the present invention is preferably obtained by alternately performing crossbreeding and screening.

The baker's yeast to be subjected to crossbreeding, mutation treatment, or cell fusion is not particularly limited, and may be naturally occurring yeast or yeast obtained by artificial treatment. In addition, commercially available yeast may be used, or a deposited strain described later may be used.

According to a preferred embodiment of the present invention, the baker's yeast of the present invention is obtained by crossing a plurality of baker's yeasts to obtain a plurality of hybrid strains, and among the plurality of hybrid strains, It is preferably produced by a method comprising the step of selecting baker's yeast. To describe more specific procedures, it is preferable to carry out the following screening steps (1) to (3) for production.

Note that the terms used in this specification have the same meanings as those commonly used in the art, unless otherwise specified below. In the present specification, the blending ratio of the main and secondary ingredients for bread (to flour, parts by weight), including the sugar blending ratio, is the blending amount (parts by weight) per 100 parts by weight of flour in the whole dough, unless otherwise specified. , so-called baker's %, and the blending amount is defined as the blending ratio (parts by weight) of the main and auxiliary raw materials for bread making. In the present invention, the term "high ethanol condition" specifically refers to a state in which the ratio (w/w) of ethanol contained in the dough immediately after kneading is 7000 ppm or more.

(Screening step (1))
In the screening step (1), a spore strain (a), a spore strain (b) and a spore strain (c) are obtained. The yeast used as a selection target in the screening step (1) may be yeast isolated from natural soil, rivers, fruits, etc., and spore strains are obtained from the yeast isolated in this way, and these are appropriately used. It may be a yeast obtained by combining and hybridizing by a conventional method. In addition, commercially available yeast may be used, or a deposited strain described later may be used. Furthermore, it may be a yeast obtained by crossing the deposited strains described later, or a yeast obtained by crossing the deposited strain described later with another yeast.

Spore strain (a) is obtained as follows. That is, according to Table 1, formulation 1 (strong flour: 100 parts by weight, white sugar: 15 parts by weight, salt: 1.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight, water: 58 parts by weight , Ethanol (99.5% (w / w)): 1.82 parts by weight, per 50 g of dough prepared under Condition 1 (mix for 3 minutes to obtain dough, then ferment the dough for 1 hour at 38 ° C.) Yeast (polyploid) is selected using as an indicator that the amount of gas generated is 160 ml or more, the yeast is sporulated, and the spores are separated to obtain a spore strain (a).

The amount of gas generated means the amount of gas generated when the dough is fermented, and indicates the fermentation power of the yeast. By measuring the amount of gas generated by a dough containing a high concentration of ethanol, it is possible to estimate the fermentation function of the dough under high ethanol conditions with the addition of fermentation seeds. In this step, if the amount of gas generated per 50 g of the medium sugar dough produced in Formulation 1 and Condition 1 is 160 ml or more as an indicator, in the final screening step (3) by cross breeding, the amount of gas generated is 180 ml or more. , making it easy to obtain yeast that has the ability to ferment medium-sugar dough under high-ethanol conditions.

Spore strain (b) is obtained as follows. That is, according to Table 1, formulation 2 (strong flour: 100 parts by weight, white sugar: 30 parts by weight, salt: 0.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight, water: 52 parts by weight , Ethanol (99.5% (w / w): 1.90 parts by weight), Yeast (polyploid) is selected as an indicator that the amount of gas generated per 50 g of the dough prepared under Condition 1 is 110 ml or more. Then, the yeast is allowed to form spores, and the spores are separated to obtain a spore strain (b).

In this step, if the amount of gas generated per 50 g of the high-sugar dough produced in Formulation 2, Condition 1 is 110 ml or more as an indicator, in the final screening step (3) by cross breeding, the gas generation amount is 130 ml or more. , making it easy to obtain yeast that has the ability to ferment high-sugar dough under high-ethanol conditions.

Spore strain (c) is obtained as follows. That is, according to Table 1, formulation 3 (strong flour: 100 parts by weight, white sugar: 40 parts by weight, salt: 0.5 parts by weight, baker's yeast (moisture content 65% wet cells): 4 parts by weight, water: 47 parts by weight , Ethanol (99.5% (w / w): 1.94 parts by weight), Yeast (polyploid) is selected as an indicator that the amount of gas generated per 50 g of the dough prepared under Condition 1 is 50 ml or more. Then, the yeast is sporulated, and the spores are separated to obtain a spore strain (c).

In this step, if the amount of gas generated per 50 g of the ultra-high sugar dough produced in Formulation 3, Condition 1 is 50 ml or more as an indicator, in the final screening step (3) by cross breeding, the amount of gas generated is 70 ml. As described above, it becomes easy to obtain yeast having the function of fermenting an ultra-high sugar dough under high ethanol conditions.

(Screening step (2))
In the screening step (2), the spore strain (b) and the spore strain (c) obtained in the screening step (1) are used to obtain the spore strain (d).

Specifically, a spore strain (d) is obtained by the method shown below. That is, the spore strain (b) and the spore strain (c) are crossed according to a conventional method to obtain a plurality of first-generation yeast (polyploid). Among these first-generation yeast (polyploid), the amount of gas generated per 50 g of the dough prepared under the above formulation 2 and the condition 1 is 125 ml or more, and the dough produced under the above formulation 3 and the above condition 1 is 50 g Yeast (polyploid) is selected using as an indicator that the amount of gas generated is 65 ml or more, the yeast is sporulated, and the spores are separated to obtain a spore strain (d).

In this step, the amount of gas generated per 50 g of the high-sugar dough prepared in Formulation 2, Condition 1 is 125 ml or more, and the amount of gas generated per 50 g of the ultra-high-sugar dough prepared in Formulation 3, Condition 1 is 65 ml or more. Using this as an index, in the final screening step (3) by crossbreeding, it becomes easy to obtain yeast that has both high-sugar dough fermentation function and ultra-high-sugar dough fermentation function under high ethanol conditions.

(Screening step (3))
In the screening step (3), the baker's yeast of the present invention is obtained using the spore strain (a) obtained in the screening step (1) and the spore strain (d) obtained in the screening step (2).

Specifically, first, the spore strain (a) and the spore strain (d) are crossed according to a conventional method to obtain a plurality of second-generation yeast (polyploid). Among these second-generation yeasts (polyploids), the amount of gas generated per 50 g of the dough prepared under the above formulation 1 and the condition 1 is 180 ml or more, and the dough produced under the above formulation 2 and the above condition 1 is 50 g Yeast (polyploid) is selected based on the indicators that the amount of gas generated is 130 ml or more and the amount of gas generated per 50 g of the dough prepared according to the above formulation 3 and condition 1 is 70 ml or more. Thereby, the baker's yeast of the present invention can be obtained.

In this step, the amount of gas generated per 50 g of the medium-sugar dough prepared in Formulation 1, Condition 1 is 180 ml or more, and the amount of gas generated per 50 g of the high-sugar dough prepared in Formulation 2, Condition 1 is 130 ml or more. In addition, if the amount of gas generated per 50 g of the ultra-high sugar dough prepared in Formulation 3, Condition 1 is 70 ml or more as an index, medium sugar dough, high sugar dough and ultra-high sugar dough under high ethanol conditions , it is possible to obtain a yeast having a fermenting power exceeding existing yeast having a high fermenting power.

In the above screening steps (1) to (3), the amount of gas generated is measured using Fermograph II (manufactured by ATTO) when 20 g of the divided dough is fermented for 1 hour at 38 ° C. Then, by multiplying the obtained value of the total gas amount by 2.5, the total gas amount per 50 g of dough can be calculated.

In the above description, the term "wet cells with 65% water content" means wet cells with 65% water content. Yeast with a moisture content of 65% wet cells can be obtained as follows. 5 ml of the medium having the composition shown in Table 2 is dispensed into a large test tube and 50 ml into a 500 ml Sakaguchi flask, sterilized in an autoclave, and then used for culture. One platinum loop of the slant-preserved yeast is inoculated into a large test tube, shake-cultured at 30°C for 1 day, transferred to a 500-ml Sakaguchi flask, and further shake-cultured at 30°C for 1 day. The cells thus prepared are centrifuged at 2000 rpm for 5 minutes and dehydrated by suction with a Nutsche to obtain wet cells. Then, the water content of the wet cells is measured, and when the wet cells are used, the amount of the wet cells used is adjusted so that the pure amount of yeast in the formulation matches.

The baker's yeast obtained through the screening steps (1) to (3) as described above exhibits a gas generation amount of 180 ml or more per 50 g of dough prepared under Formulation 1, Condition 1, and was produced under Formulation 2, Condition 1. The baker's yeast exhibits a gas generation amount of 130 ml or more per 50 g of the dough, and further exhibits a gas generation amount of 70 ml or more per 50 g of the dough prepared according to Formulation 3, Condition 1.

As described above, the baker's yeast of the present invention exhibits a high gas generation rate in medium-sugar dough, high-sugar dough and ultra-high-sugar dough containing high-concentration ethanol that causes fermentation inhibition. By using the baker's yeast, it is possible to obtain bread with a soft texture and a sufficient flavor characteristic of the ethanol-containing fermented yeast, without the extension of the proofing time during bread making and lack of volume of the bread.

Although an embodiment in which the baker's yeast of the present invention is obtained through the screening steps (1) to (3) has been described above, the baker's yeast of the present invention is not limited to those that have undergone the above screening steps. As described above, the amount of gas generated per 50 g of the dough prepared under Formulation 1, Condition 1 is 180 ml or more, and the amount of gas generated per 50 g of dough prepared under Formulation 2, Condition 1 is 130 ml or more. 3. If it exhibits the function of generating 70 ml or more of gas per 50 g of the dough prepared under Condition 1, it corresponds to the baker's yeast of the present invention.

The baker's yeast of the present invention can also be obtained by performing only the screening step (3) without performing the screening steps (1) and (2). When the screening steps (1) and (2) are not performed, the yeast used as a selection target in the screening step (3) is obtained by crossing the spore strain (a) and the spore strain (d) as described above according to a conventional method. It is not limited to second generation yeast obtained. It may be a yeast isolated from soil, rivers, fruits, etc. in the natural world, or a yeast obtained by obtaining spore strains from the yeast isolated in this way, appropriately combining them, and hybridizing them by a conventional method. There may be. In addition, commercially available yeast may be used, or a deposited strain described later may be used. Furthermore, it may be a yeast obtained by crossing the deposited strains described later, or a yeast obtained by crossing the deposited strain described later with another yeast. However, by performing the screening steps (1) and (2) before the screening step (3), the baker's yeast of the present invention can be obtained more reliably.

As the baker's yeast of the present invention, baker's yeast belonging to Saccharomyces cerevisiae is preferably selected, and Saccharomyces cerevisiae KCY1278 strain, Saccharomyces cerevisiae KCY1279 strain or Saccharomyces cerevisiae KCY1280 strain has been obtained. The KCY1278 strain, KCY1279 strain, and KCY1280 strain are transferred from Saccharomyces cerevisiae "NITE BP-02462 (original deposit date) NITE P-02462, which was deposited on April 25, 2017. Transfer date: April 2018 17th)”, “NITE BP-02463 (Transferred from NITE P-02463 deposited on April 25, 2017 (original deposit date). Transfer date: April 17, 2018)”, “NITE BP-02464 (Transferred from NITE P-02464 deposited on April 25, 2017 (original deposit date). Transfer date: April 17, 2018)”, the National Institute of Technology and Evaluation Patent Microorganism Depositary Center (Japan (Room 122, 2-5-8 Kazusa Kamatari, Kisarazu City, Chiba Prefecture).

The baker's yeast of the present invention may be in the form of fresh yeast, or may be prepared in the form of dry yeast according to a conventional method.

The baker's yeast of the present invention can be suitably used when making bread to which ethanol-containing fermented seeds such as sake seeds and old noodle seeds are added. In particular, by adding ethanol-containing fermented seeds, the ratio of ethanol contained in the bread dough (w / w) becomes 7000 ppm or more, and conventionally fermentation inhibition by ethanol has been a problem for bread dough under high ethanol conditions. , can be preferably used. However, since the baker's yeast of the present invention has a high fermenting power in bread dough containing a high concentration of ethanol, even if ethanol-containing fermented seeds are not added, the ethanol content (w / w) in the bread dough is 7000 ppm or more. It can be suitably used for bread dough. Further, when the bread dough contains 15 to 40 parts by weight of sugar per 100 parts by weight of wheat flour, the effects of the present invention are achieved more reliably.

The baker's yeast of the present invention can be used in both the straight method of bread making by one-step fermentation and the sponge dough method of bread making by two-step fermentation, but it can be preferably used in the sponge dough method. . In the sponge method, first, 55 to 75% of the total amount of wheat flour, all or part of baker's yeast, and part of water are mixed to prepare a sponge dough, which is fermented for a predetermined time (fermentation of sponge). After that, the rest of the ingredients are added to this medium dough, mixed again (main kneading), fermented again, and bread is made. Since the baker's yeast of the present invention exhibits ethanol tolerance, it can be suitably used as a baker's yeast (additional seed) that is additionally added to a sponge dough after fermentation containing a high concentration of ethanol. In the case of adding the fermented seeds by the sponge dough method, it is preferable to add the fermented seeds additionally to the sponge dough after fermentation of the sponge dough, but the method is not limited to this.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. In the following, "parts" and "%" are based on weight unless otherwise specified.

<Preparation of bacterial cells for screening>
65% wet yeast cells used in the following screening were obtained as follows. 5 ml of the medium having the composition shown in Table 2 was dispensed into a large test tube and 50 ml into a 500 ml Sakaguchi flask, sterilized in an autoclave, and then used for culture. One platinum loop of yeast stored in a slant was inoculated into a large test tube, cultured with shaking at 30°C for 1 day, then transferred to a 500 ml Sakaguchi flask, and further cultured with shaking at 30°C for 1 day. The cells thus prepared were centrifuged at 2000 rpm for 5 minutes and dehydrated by suction with a Nutsche to obtain wet cells. Then, the moisture content of the wet cells was measured, and when using the wet cells, the amount of the wet cells used was adjusted so that the pure amount of the yeast in the formulation was matched.

<Preparation of bread-making fungus>
In Examples and Comparative Examples, culture was performed as follows in order to obtain baker's yeast to be subjected to bread-making tests.

(batch culture)
5 ml of the medium having the composition shown in Table 2 was dispensed into a large test tube and 50 ml into a 500 ml Sakaguchi flask, sterilized in an autoclave, and then used for culture. One platinum loop of the breeding strain was completely inoculated into a large test tube, cultured with shaking at 30°C for 1 day, then transferred to a 500 ml Sakaguchi flask, and further cultured with shaking at 30°C for 1 day. The prepared batch-cultured cells were subjected to seed culture in the following 5 L jar. In preparing the medium, molasses was used as sugar, and the amount of molasses used was adjusted so that the sugar concentration in the medium was 4% (w/v).

(5L jar seed culture)
2 L of the medium having the composition shown in Table 3 was placed in a 5 L jar, and after autoclave sterilization, five 500 ml Sakaguchi flasks of batch-cultured cells were inoculated, and seed culture was performed under the conditions shown in Table 4. In preparing the medium, molasses was used as sugar, and the amount of molasses used was adjusted so that the sugar concentration in the medium was 4% (w/v).

(5L jar main culture)
A medium having the composition shown in Table 5 was used as the starting solution, and 50 g of wet cells cultured in a 5 L jar were added to the culture medium, and main culture was carried out under the conditions shown in Table 6. In the main culture, culture was performed for 13 hours, and sugar was added in portions. Immediately after the completion of the main culture, the cells were centrifuged and dehydrated by suction with a Nutsche to prepare wet cells, which were used for the following screening. When evaluating the fermentation power in the screening, the amount of gas generated from each bread dough was measured by the method described below.

<Gas generation amount measurement>
Nisshin Seifun's hard flour camellia is used as wheat flour, and a suspension containing a specified amount of white sugar, water, salt, and ethanol is prepared, mixed with baker's yeast, and kneaded for 3 minutes with a Hobart desktop mixer. bottom. The amount of gas generated from 20 g of the dough after kneading is measured at 38 ° C. for 1 hour using Fermograph II (manufactured by ATTO), and the total amount of gas obtained is multiplied by 2.5, which corresponds to 50 g of the dough after kneading. The total amount of gas was obtained, and the amount of gas was defined as the amount of gas generated by each baker's yeast. Unless otherwise specified, the blending ratio (%) of raw materials is the weight ratio to 100 wheat flour in the whole dough, so-called baker's %, and the amount of baker's yeast is the amount equivalent to the wet cells that account for 65% of the moisture. show.

In addition, regarding the ingredients used in the following bread making, the wheat flour used is strong flour “Camellia” (manufactured by Nisshin Flour Milling Co., Ltd.) and “Auchion” (manufactured by Nisshin Flour Milling Co., Ltd.), and the yeast food is “New Food C” (Kaneka company), emulsifier “Panmac 200V” (Riken Vitamin), and shortening “Snowlight” (Kaneka). Other baking ingredients and baking sub-ingredients were available from general retailers.

The amount of yeast used in the evaluation of bread making in the Examples was described as the amount of wet cells in which water accounts for 65%. When the moisture content of the cells actually used is different from 65%, the amount of the cells used is adjusted so that the pure amount of the yeast in the formulation matches. Adjusted for body water content.

<Measurement of proof gas generation amount>
The amount of gas in 20 g of the dough after mixing prepared in the example was measured using Fermograph II (manufactured by ATTO) at 38 ° C. for 55 minutes, and the total amount of gas obtained was multiplied by 2.5 to obtain the dough. The total gas amount per 50 g was calculated. This was taken as the amount of proof gas generated.

<Preliminary time measurement>
350 g of the dough prepared in the example was placed in a one-loaf mold, proofed (temperature 39 ° C. / humidity 86%), and the time required for the expansion of the dough to reach 10 mm above the one-loaf mold was measured. This was taken as the proof time.

<Measurement of specific volume of bread>
Put 350 g of the dough prepared in the example in a one-loaf mold, perform proof fermentation (temperature 39 ° C. / humidity 86% / 55 minutes), store the baked bread at 25 ° C. for 24 hours, and measure the weight and volume of the bread with a laser. It was measured with a volume meter (manufactured by Astec). The specific volume of the bread was calculated from the weight and volume obtained.

<Sensory evaluation of bread>
After baking, the one-loaf was placed in a bag, sealed and stored at 25° C. for one day, and sliced into 1.5 cm wide slices to obtain a sample. The evaluation was performed by 10 people, and each person ate the sample and evaluated the rich liquor-like flavor derived from the fermented seeds (sake seeds) exhibited by the bread and the softness of the bread on a scale of 10, and the average value was calculated. Calculated. In addition, the evaluation of the flavor is a relative evaluation when the flavor of the bread of Comparative Example 5 in which sake seeds are added in a general amount (5%) is set to 5 points, and the evaluation of the softness is the same. A relative evaluation was made when the softness of the bread of Comparative Example 5 was set to 5 points.

(Examples 1 to 3) Acquisition of strains KCY1278, KCY1279, and KCY1280 (Preparation of bacterial cells for screening)
Saccharomyces cerevisiae strain (diploid) isolated from soil and plants in Japan (Tohoku region: 380 samples/1167 isolates, Shikoku region: 236 samples/695 isolates, Chugoku region 347 samples/468 isolates, Kyushu Local: 294 samples / 752 isolates, other: 55 samples / 111 isolates), 30 kinds of hybrid strains were prepared from a number of randomly selected combinations, and the <Screening fungus Preparation> to obtain yeast (polyploid) as wet cells with a moisture content of 65%.

(Screening step (1)-1: Acquisition of spore strain (a))
From the 30 types of yeast (polyploid) obtained above, 10 strains of yeast (polyploid) with a gas generation amount of 160 ml or more per 50 g of the dough prepared according to Formulation 1 and Condition 1 listed in Table 1 were selected. selected. When these yeasts (polyploids) were identified, they were all Saccharomyces cerevisiae, and the strain with a particularly high gas generation amount of 186 ml was designated as NITE BP-02461 (KCY1275 strain). Transferred from NITE P-02461 deposited at the Microorganism Depository Center (Room 122, 2-5-8 Kazusa Kamatari, Kisarazu City, Chiba Prefecture, Japan) (transferred from NITE P-02461 deposited on April 25, 2017 (original date of deposit). Date of transfer: April 17, 2018). The selected 10 strains of yeast (polyploid) were allowed to form spores, and a total of 40 spore strains obtained by separating the spores were designated as spore strains (a).

(Screening step (1)-2: Acquisition of spore strain (b))
Among the 30 types of yeast (polyploid) obtained in the preparation of the screening fungus, the yeast that generated 110 ml or more of gas per 50 g of the dough prepared according to Formulation 2 and Condition 1 listed in Table 1 ( Polyploid) 8 strains were selected. Among these eight strains, one strain was commercially available Kaneka Yeast DR (trade name) manufactured by Kaneka Corporation, and the amount of gas generated was 133 ml. These 8 strains of baker's yeast (polyploid) were allowed to form spores, and 32 kinds of spore strains obtained by separating the spores were designated as spore strains (b).

(Screening step (1)-3: Acquisition of spore strain (c))
Among the 30 types of yeast (polyploid) obtained in the preparation of the screening fungus, the yeast that generated 50 ml or more of gas per 50 g of the dough prepared according to Formulation 3 and Condition 1 listed in Table 1 ( Polyploid) 10 strains were selected. Among these 10 strains, one strain was commercially available Kaneka East TR (trade name) manufactured by Kaneka Corporation, and the amount of gas generated was 60 ml. These 10 strains of baker's yeast (polyploid) were sporulated, and 40 spore strains obtained by separating the spores were designated as spore strain (c).

(Screening step (2): Acquisition of spore strain (d))
The spore strain (b) and the spore strain (c) are crossed according to a conventional method to obtain 30 kinds of first-generation hybrid strains, which are cultured according to the <Preparation of screening cells>. got a body Among the 30 first-generation hybrid strains obtained, the amount of gas generated per 50 g of the dough prepared under Formulation 2, Condition 1 is 125 ml or more, and the amount of gas generated per 50 g of the dough prepared under Formulation 3, Condition 1 is Seven strains of baker's yeast (polyploid) with a gas generation amount of 65 ml or more were selected. These 7 strains of baker's yeast (polyploid) were sporulated, and 28 spore strains obtained by separating the spores were designated as spore strain (d).

(Screening step (3): Acquisition of KCY1278, KCY1279, and KCY1280 strains)
The spore strain (a) and the spore strain (d) are hybridized according to a conventional method to obtain 20 second-generation hybrid strains, cultured according to the <Preparation of screening cells>, and wet cells with a moisture content of 65%. Obtained. Among the 20 second-generation hybrid strains obtained, the amount of gas generated per 50 g of the dough prepared under Formulation 1, Condition 1 is 180 ml or more, and the amount of gas generated per 50 g of the dough prepared under Formulation 2, Condition 1 is A plurality of baker's yeast (polyploid) with a gas generation amount of 130 ml or more and a gas generation amount of 70 ml or more per 50 g of the dough prepared according to Formulation 3, Condition 1 was obtained.

Three of them were identified, and all were Saccharomyces cerevisiae. Receipt number: NITE BP-02462 (KCY1278 strain, Example 1), Receipt number: NITE BP-02463 (KCY1279 strain, Example 2), Receipt number: NITE BP-02464 (KCY1280 strain, Example 3 ) was deposited at the National Institute of Technology and Evaluation Patent Microorganisms Depositary Center (Room 122, 2-5-8 Kazusa Kamatari, Kisarazu City, Chiba Prefecture, Japan).

Table 7 shows the amount of gas generated per 50 g of the fabrics produced using the KCY1278 strain, KCY1279 strain, or KCY1280 strain under Formulations 1 to 3 and Condition 1.

(Comparative Example 1) KCY1275 Strain Table 7 shows the amount of gas generated per 50 g of the dough prepared under conditions 1 under Formulations 1 to 3 using the KCY1275 strain obtained in the above (screening step (1)-1).

(Comparative Example 2) Kaneka East DR manufactured by Kaneka Corporation
Table 7 shows the amount of gas generated per 50 g of the dough prepared in Formulations 1 to 3 and Condition 1 using the commercially available Kaneka Yeast DR manufactured by Kaneka Co., Ltd. obtained in the above (screening step (1)-2). .

(Comparative Example 3) Kaneka East TR manufactured by Kaneka Corporation
Table 7 shows the amount of gas generated per 50 g of the dough prepared in Formulations 1 to 3 under Condition 1 using the commercially available Kaneka Yeast TR manufactured by Kaneka Co., Ltd. obtained in the above (screening step (1)-3). .

From the above results, the KCY1278 strain, KCY1279 strain, and KCY1280 strain of the present invention are higher in medium-sugar, high-sugar, and ultra-high-sugar blended doughs containing high concentrations of ethanol compared to commercially available baker's yeast. It can be said that the fermentation function in the presence of ethanol is high, indicating the amount of gas generated.

(Example 4-6) Bread making test with 15% sake seed addition Using the above-mentioned KCY1278 strain (Example 4), KCY1279 strain (Example 5), and KCY1280 strain (Example 6), the formulations described in Table 8 4, Bread dough was prepared according to the steps described in Table 9. The amount of proofing gas generated, the proofing time, and the specific volume (volume) of the bread prepared by baking each bread dough under the conditions shown in Table 9 were measured, and the results are shown in Table 10. Furthermore, as a sensory evaluation, the flavor and softness (texture) of the bread were evaluated, and the results are shown in Table 10.

(Comparative Example 4) Bread-making test with addition of 15% sake type Kaneka yeast TR manufactured by Kaneka Co., Ltd. was used to prepare bread dough according to formulation 4 shown in Table 8 and the steps shown in Table 9, and the bread dough was made under the conditions shown in Table 9. Bread was prepared by baking. Measurements and evaluations were carried out in the same manner as in Examples 4 to 6, and the results are shown in Table 10.

(Comparative Example 5) Bread-making test with 5% alcoholic beverages Bread dough was prepared using Kaneka Yeast TR manufactured by Kaneka Co., Ltd., using the formulation 5 described in Table 8 and the process described in Table 9, with the amount of alcoholic beverages changed to a general amount. The bread dough was baked under the conditions shown in Table 9 to prepare bread. Measurements and evaluations were carried out in the same manner as in Examples 4 to 6, and the results are shown in Table 10.

From the results shown in Table 10, the baker's yeast according to the present invention (KCY1278 strain, implemented Example 4, KCY1279 strain/Example 5, KCY1280 strain/Example 6) has a shorter proofing time, a larger bread volume, and a softer texture than Kaneka East TR manufactured by Kaneka Corporation in Comparative Example 4. It can be seen that the bread quality is excellent.

Furthermore, using the baker's yeast according to the present invention (KCY1278 strain, Example 4, KCY1279 strain, Example 5, KCY1280 strain, Example 6), 3 times the amount of sake used is generally used. The bread (the ethanol concentration in the dough is about 10000 ppm) is a bread (the ethanol concentration in the dough is is about 3500 ppm), there is no delay in proofing time, the bread volume is comparable, the flavor can be improved, and the texture is soft.

That is, the baker's yeast (KCY1278 strain, KCY1279 strain, KCY1280 strain) according to the present invention exhibits good bread quality under dough conditions in which a high concentration of ethanol is present. It is added to allow the efficient production of high-volume, soft bread. In addition, the baker's yeast according to the present invention exhibits high fermentation power in medium-sugar dough, high-sugar dough, and ultra-high-sugar dough in which ethanol is present at a high concentration, and can efficiently produce soft bread with a large volume from each dough. make it possible to create

Claims (7)

Saccharomyces cerevisiae KCY1278 with accession number: NITE BP-02462, Saccharomyces cerevisiae KCY1279 with accession number: NITE BP-02463 , or Saccharomyces cerevisiae KCY1280 with accession number: NITE BP-02464 . The baker's yeast according to claim 1 is cross-breeding, mutation treatment, or cell fusion baker's yeast,
The amount of gas generated per 50 g of the dough prepared under Formulation 1, Condition 1 is 180 ml or more,
Formulation 2, the amount of gas generated per 50 g of the fabric produced under condition 1 is 130 ml or more, and
Formulation 3, the amount of gas generated per 50 g of the fabric produced under condition 1 is 70 ml or more ,
The above formulation 1 is: strong flour: 100 parts by weight, white sugar: 15 parts by weight, salt: 1.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 58 parts by weight, 99.5 w /w% ethanol: 1.82 parts by weight,
The condition 1 is a condition that after mixing for 3 minutes to obtain a dough, the dough is fermented at 38 ° C. for 1 hour,
The above formulation 2 is: strong flour: 100 parts by weight, white sugar: 30 parts by weight, salt: 0.5 parts by weight, baker's yeast that is a 65% moisture content wet cell: 4 parts by weight, water: 52 parts by weight, 99.5 w /w% ethanol: 1.90 parts by weight,
The above formulation 3 is: strong flour: 100 parts by weight, white sugar: 40 parts by weight, salt: 0.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 47 parts by weight, 99.5 w /w % ethanol: baker's yeast, which is 1.94 parts by weight. Bread dough containing the baker's yeast according to claim 1 or 2. The bread dough according to claim 3, which has an ethanol concentration of 7000 ppm or more. Bread prepared by cooking the bread dough according to claim 3 or 4. A method for screening baker 's yeast, comprising:
The amount of gas generated per 50 g of the dough prepared under Formulation 1, Condition 1 is 180 ml or more,
Formulation 2, the amount of gas generated per 50 g of the fabric produced under condition 1 is 130 ml or more, and
Formulation 3, selecting polyploids of baker's yeast belonging to Saccharomyces cerevisiae, using as an indicator that the amount of gas generated per 50 g of dough prepared under Condition 1 is 70 ml or more ,
The above formulation 1 is: strong flour: 100 parts by weight, white sugar: 15 parts by weight, salt: 1.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 58 parts by weight, 99.5 w /w% ethanol: 1.82 parts by weight,
The condition 1 is a condition that after mixing for 3 minutes to obtain a dough, the dough is fermented at 38 ° C. for 1 hour,
The above formulation 2 is: strong flour: 100 parts by weight, white sugar: 30 parts by weight, salt: 0.5 parts by weight, baker's yeast that is a 65% moisture content wet cell: 4 parts by weight, water: 52 parts by weight, 99.5 w /w% ethanol: 1.90 parts by weight,
The above formulation 3 is: strong flour: 100 parts by weight, white sugar: 40 parts by weight, salt: 0.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 47 parts by weight, 99.5 w /w% ethanol: 1.94 parts by weight , screening method for baker's yeast . A method for producing baker's yeast, comprising:
A step of crossbreeding baker's yeast to obtain a plurality of hybrid strains, and a step of selecting baker's yeast from among the plurality of hybrid strains according to the following indicators ,
The indicator is
The amount of gas generated per 50 g of the dough prepared under Formulation 1, Condition 1 is 180 ml or more,
Formulation 2, the amount of gas generated per 50 g of the fabric produced under condition 1 is 130 ml or more, and
Formulation 3, the amount of gas generated per 50 g of the dough prepared under Condition 1 is 70 ml or more ,
The above formulation 1 is: strong flour: 100 parts by weight, white sugar: 15 parts by weight, salt: 1.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 58 parts by weight, 99.5 w /w% ethanol: 1.82 parts by weight,
The condition 1 is a condition that after mixing for 3 minutes to obtain a dough, the dough is fermented at 38 ° C. for 1 hour,
The above formulation 2 is: strong flour: 100 parts by weight, white sugar: 30 parts by weight, salt: 0.5 parts by weight, baker's yeast that is a 65% moisture content wet cell: 4 parts by weight, water: 52 parts by weight, 99.5 w /w% ethanol: 1.90 parts by weight,
The above formulation 3 is: strong flour: 100 parts by weight, white sugar: 40 parts by weight, salt: 0.5 parts by weight, baker's yeast that is 65% moisture content wet cells: 4 parts by weight, water: 47 parts by weight, 99.5 w /w% ethanol: 1.94 parts by weight.