JP2001178449A - Yeast, frozen bread dough, dry bread yeast, fermented food, and method for producing salt-containing fermented food and fermented food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing food products through making use of the high stress resistance of fermentable natural yeast, in view of the manufacturing industry for various fermented foods using such natural yeast. SOLUTION: This method comprises using Saccharomyces cerevisiae (FERM P-17573), a kind of yeast with high stress resistance, isolated from leaf mould found in deciduous broad-leaved forest zones in the Temperate Zone. Using the yeast, bread with dampish palate feeling is produced. Bread with adequate date of minimum durability is produced by one of various breadmaking methods involving stress load on yeast and including frozen dough breadmaking method. Alternatively, dry yeast is prepared from the above-mentioned yeast and used in breadmaking activities. By making use of the fact that the above yeast has high fermentative power even at high saline concentrations, the yeast is used in manufacturing miso/soy sauce and for flavoring in manufacturing pickles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a highly stress-tolerant yeast Saccharomyces cerevisiae isolated from a temperate deciduous broad-leaved forest zone. In the field of fermented foods such as bread, which is extremely in demand in Japan, and traditional foods such as miso, soy sauce, and pickles, naturally-derived stress-resistant yeast is strongly demanded. In response to.

[0002]

2. Description of the Related Art Conventionally, the use of natural yeast in the bakery industry involves seeding from fruits and the like and using it for a period that can maintain breadmaking suitability. Has been adopted.

[0003] In addition, the only yeast used in the frozen dough baking method that has become popular in recent years is a freeze-tolerant yeast bred from a conventional baker's yeast by a yeast manufacturer.

[0004] Further, the dry yeast for bread making has also been limited to those obtained by breeding from baker's yeast by a yeast manufacturer and drying and granulating the yeast produced by a special culturing method.

Hitherto, the use of yeast in salt-containing fermented foods such as pickles, miso, and soy sauce has been limited to halophilic yeasts such as Zygosaccharomyces rouxii.

[0006]

However, since bread cannot be stably fermented in bread making using naturally brewed natural yeast, bread making requires skill.

[0007] The use of natural yeast in the frozen dough baking method is as follows.
This has not been done so far because there is no natural yeast having sufficient freezing tolerance.

[0008] Furthermore, the drying and granulation of natural yeast by the conventional method has not been produced due to the low drying resistance.

In salt-containing fermented foods, attempts have been made to use Saccharomyces cerevisiae having higher fermentative power and aroma-producing ability than halophilic yeasts such as Digosaccharomyces luxii, but Saccharomyces cerevisiae has a low salt tolerance. Had not been put to practical use.

[0010]

SUMMARY OF THE INVENTION The present invention provides a method for separating natural yeasts for fermented foods from the natural world, in which a stress load from nature is large and a temperate deciduous broad-leaved forest zone is located at 40 degrees north of latitude which is unopened soil. Humic soil was the source of separation.

As a result of vigorous separation, the same yeast belonging to Saccharomyces cerevisiae as a conventional bread yeast was successfully separated from mulch. As a result of the bread making test, this yeast has excellent fermentation performance in both the scratch baking method and the frozen dough baking method, and retains its fermentation performance even when dried, so it can be used as a dry yeast for baking. there were. In addition, it showed sufficient fermentation performance even at a high salt concentration, and was confirmed to be usable for salt-containing fermented foods such as pickles, miso, and soy sauce, and thus completed the present invention.

The yeast strain ARIF KD-003 used in the present invention was isolated from mulch by the following method. [Strain isolation and identification] 200 g of chloramphenicol was obtained from this buffered yeast obtained with the permission of the competent authority from the buffer area of the "Shirakami-Sanchi" natural world heritage in Fujisato-cho, Yamamoto-gun, Akita Prefecture.
m, glucose 0.3g, peptone 0.1g, yeast extract 0.05g, tap water
Place in a medium with a composition of 10 ml, 25-26 ° C, 5 cm at 5 cm amplitude.
After shaking culture for 7 days to measure the yeast growth, the yeast was cultured in a koji juice agar medium consisting of 50 g of powdered koji extract, 15 g of agar, 1,000 ml of tap water and pH 5.0 at 27 ° C. for 3 days, and then purified. It is separated into

The method of Van Der Walt and D. Yallow [The Yea
sts, a Taxonomic Study (Ed.by NJWKerger-van Ri
j) Elsevier Science Publishers, 45-104 (1984)], the taxonomic properties of the food ARIF KD-003 strain are as follows.

Propagation method: Multipolar sprouting Vegetative cell shape: oval, sphere Vegetative cell size: (4.0-1.0) × (4.0-15.0) μm Ascospore formation: Ascospore shape: sphere Capsule formation mode: vegetative cells directly become ascospores Number of ascospores: 1 to 4 Sugar fermentation glucose: + galactose: + sucrose: + maltose: + lactose:-raffinose: + melibiose:-carbon Compound assimilation glucose: + galactose: + ribose:-L-rhamnose:-D-arabinose:-L-arabinose-xylose:-sucrose: + maltose: + lactose:-trehalose: + melezitose: + sorbose:- Melibiose:-Cellobiose:-Raffinose: + Soluble starch:-Ethyl alcohol: + Glycerol: + Erythritol:-Glutitol:-Glass Tititol:-Mannitol:-Inositol:-Arbutin:-Inulin:-Salicin:-Succinic acid:-Citric acid:-DL-lactic acid:-α-Methylglucoside:-Ethylamine:-Utilization of nitrate:-Vitamin-deficient medium Growth on + 37 ° C .: + 50% glucose-yeast extract on agar medium: + Urease activity: − GBB test: −

The yeast grows by multipolar budding, the vegetative cells directly form ascospores to form 1 to 4 spherical ascospores, ferment glucose, and do not assimilate nitrate. [The Yeasts, a Taxonomic Study (Ed.by NJW
Kerger-van Rij) Elsevier Science Publishers, 379-398
(1984)] according to Sacchlomyces cerevisiae.
aromyces cerevisiae) and the strain number as ARIF KD-0
03. This strain has been deposited at the Institute of Biotechnology, Institute of Biotechnology, Institute of Biotechnology, Patent Microorganisms Depositary No. 17573 (FERM P-17573).

An industrial production method of this yeast (FERM P-17573) is as follows. This is a method of culturing under aerobic conditions such as shaking culture and aeration culture while maintaining the oxygen supply ability at a high level. For example, when performing aeration culture, the amount of aeration is 1-2? / Min per 1? Of culture solution.
Ventilation is desirable.

As a carbon source, sucrose, glucose, molasses and the like can be used.

As the nitrogen source, peptone, ammonium sulfate, urea, aqueous ammonia, other vitamins such as yeast extract, and inorganic salts are used.

In the present invention, stress tolerance refers to freezing,
It means maintaining high viability and activity against physicochemical stress such as drought and high concentration salt.

Hereinafter, the present invention will be described in more detail with reference to Production Examples and Examples.

[Production example] Saccharomyces cerevisiae ARIF KD-003
(FERM P-17573) was stored in a liquid YPSu consisting of 0.5% yeast extract, 1.0% peptone, 4% sucrose and pH 5.0.
After shaking culture in a 500 ml Erlenmeyer flask using a crose medium for 50 hours, culturing was further performed with aeration and agitation at 28-30 ° C. for 30 hours in a 100-cm culture tank.

The culture was collected and washed by a centrifuge to obtain 6 kg of yeast cells having a water content of 70%.

[Low Temperature Stress Tolerance] This yeast (FERM)
P-17573) was evaluated for its resistance to low-temperature stress based on the survival rate when the collected and washed yeast was kept at a low temperature of -80 to 4 ° C for a certain period of time. In addition, the measurement of the survival rate, the unfrozen sample is the yeast as it is, and for the frozen sample, in a 37 ° C warm bath, the yeast thawed for 3 minutes is appropriately diluted with sterilized water, and yeast extract 0.5%, peptone 1.0%, Glucose 3.
0%, agar 1.5%, pH5.0 on YPD agar medium at 30 ° C, 3
This was performed by a plate measurement method in which culture was performed for one day.

Saccharomyces cerevisiae ARIF KD-00
When the strain 3 (FERM P-17573) was kept at low temperature for one month, the survival rates were -80 ° C: 63%, -50 ° C: 94%, -30 ° C.
C: 100%, -20C: 100%, -2C: 86%, + 4C: 80%. When held for 6 months, -80 ° C: 58%, -50
° C: 73%, -30 ° C: 85%, -20 ° C: 93%, -2 ° C: 63%, + 4 ° C:
Compared to the freeze-tolerant yeast for bread making that has been used so far, the yeast of the present invention (FERM P-17573) shows a higher survival rate when the yeast is manufactured and stored under the same conditions. Was.

Now, the present invention will be described in further detail with reference to Examples, but it should be understood that the present invention is by no means restricted by such specific Examples.

[0025]

Example 1 Saccharomyces sp.
Using the S. cerevisiae ARIF KD-003 (FERMP-17573) strain, the low sugar dough fermentation power was measured based on the yeast test method for bread of the Japan East Industry Association, and the amount of carbon dioxide gas generated was observed. The results are shown in Table 1.

[0026]

[Table 1]

[0027] The low sugar dough fermenting power of the normal yeast for bread is 48-57 ml, but it is Saccharomyces cerevisiae AR.
As shown in Table 1, the IF KD-003 (FERM P-17573) strain exhibited fermentation power equivalent to that of yeast for bread even though it was a natural yeast.

[0028]

[Example 2] Saccharomyces cerevisiae ARIF KD-00
Bread was manufactured using the 3 (FERM P-17573) strain by a direct kneading bread method. The production was performed according to the formulation shown in Table 2.

[0029]

[Table 2]

Saccharomyces cerevisiae ARIF KD-00
Bread using strain 3 (FERM P-17573) had a pale, thin, glossy rind, and was of high quality with a good sweetness and a moist texture.

The yeast (FERM) containing the low sugar dough shown in Table 2
P-17573) and a sensory test for comparison between bread manufactured using ordinary yeast for bread and bread manufactured using ordinary yeast for bread.
Performed by 24 panelists, the results in Table 3 were obtained.

[0032]

[Table 3]

As is clear from the above results, Saccharomyces cerevisiae ARIF KD-003 (FERM P-1
7573) Bread using the strain was preferred, and it was confirmed that the effect of using the yeast of the present invention was exhibited in a normal bread making method.

[0034]

Example 3 Saccharomyces cerevisiae ARIF KD-00
The application of 3 (FERM P-17573) strain to a frozen dough baking method was studied. Using this yeast, the solution fermented at 30 ° C. for a certain period of time was degassed, frozen and stored after defrosting, and the amount of gas generated after thawing was measured by the liquid fermentation method of the yeast test for bread of the Japan East Industry Association.

For freezing, a freezer at -20 ° C was used. After freezing, it was frozen and stored at -20 ° C for a certain period, and thawed in a warm bath at 30 ° C. After thawing, the amount of gas generated in a 30 ° C. warm bath for 1 hour is shown in Table 4.

[0036]

[Table 4]

The amount of gas generated by the liquid fermentation method is 90 to 115 ml in the case of the present yeast (FERM P-17573) when freezing is not performed. Was also considered to have little effect on gas generation.

[0038]

Example 4 A dough was produced with the low sugar dough formulation shown in Table 2,
After dough freezing and shaping freezing at 10 ° C., the bread was made after being frozen and stored for 10 days. Any freezing method can produce high-quality bread with sufficient volume and no shiny pear skin,
Saccharomyces cerevisiae ARIF KD-003 (FERM
P-17573) strain was also confirmed to be applicable to the frozen dough baking method.

[0039]

Example 5 Saccharomyces cerevisiae ARIF KD-00
3 (FERM P-17573) strain in YPSucrose medium
The yeast cells cultured with shaking at 40 ° C for 40 hours are collected and washed.
Hot air drying was performed at 30 ° C. to obtain dry yeast. Similar culture, collection, washing, and drying treatments were also performed on yeast isolated from commercially available dry yeast, and used as a control.

When the viability before and after drying was measured by a plate measurement method, Saccharomyces cerevisiae ARIF K
D-003 (FERM P-17573) strain 74%, commercially available dry yeast strain 75%, and the residual rate of gas generation measured by the above liquid fermentation method was ARIF KD-003 (FER
(MP-17573) strain was 64%, whereas that of the commercially available dry yeast strain was 60%. The moisture after drying is ARIF KD-
003 (FERM P-17573) and the commercially available dry yeast strain were 4.0%.

As described above, the dried product of the Saccharomyces cerevisiae ARIF KD-003 (FERM P-17573) strain has the same survival rate to dryness and residual gas generating power as those of the commercially available dry yeast strain. It was judged that it could be used as a better dry yeast for baking.

[0042]

Example 6 The yeast of the present invention produced according to the Production Example was
A test solution of the liquid fermentation method containing 0% NaCl at 4-30 ° C, 6
The temperature was maintained for one day, and the amount of gas generated was measured. The results shown in Table 5 were obtained.

[0043]

[Table 5]

From Table 5, it can be seen that a sufficient amount of gas is generated even at 20% NaCl and 30 ° C., so that Saccharomyces cerevisiae
ARIF KD-003 (FERM P-17573) strain can be used as yeast for brewing in the production of miso / soy sauce.
In addition, the fermentation effect is expected in the production of salt-containing fermented foods such as pickles since the amount of gas generated is good even at room temperature to low temperature.

[0045]

Example 7 A production test of fermented pickles was conducted. Saccharomyces cerevisiae ARIF KD-003 manufactured according to the manufacturing example
(FERM P-17573) 1500 g of dried radish was soaked in a fermentation solution 3 containing 3% strain, 5% salt, 5% sucrose, and 0.5% protein preparation, and fermented in a refrigerator for 7 days.

Sufficient gas generation was observed even in the refrigerator,
The radish pickles after fermentation have the same texture as conventional pickles and are of high quality with good fermentation aroma. Saccharomyces cerevisiae ARIF KD-003 (FERM P-1775)
3) It was confirmed that the strain can be used for salt-containing fermented foods.

[0047]

According to the present invention, a yeast having freezing resistance, drying resistance and salt resistance can be obtained. The yeast of the present invention has excellent fermentation performance in the scratch baking method and the frozen dough baking method, and retains its fermentation performance even when dried, so that it can be used as a dry yeast for baking.
In addition, it shows sufficient fermentation performance even at a high salt concentration and can be used for salt-containing fermented foods such as pickles, miso, and soy sauce.

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Claims (6)

[Claims] 1. The yeast Saccharomyces cerevisiae ARIF KD-003 (FER), which has stress tolerance.
MP-17573). 2. A frozen bread dough comprising the yeast according to claim 1. 3. A dried baker's yeast obtained by drying the yeast according to claim 1. 4. A fermented food produced by using the yeast according to claim 1. 5. A salt-containing fermented food produced by using the yeast according to claim 1. 6. A method for producing a fermented food, comprising a process of fermenting using the yeast according to claim 1.