JPH0336499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing yeast extract by autolysis.

Conventionally, an autolysis method has been known as a method for producing yeast extract.

Autolysis is a method of enzymatic decomposition using yeast cells' own enzymes, and since live yeast cells, especially fresh cells obtained by culturing, are difficult to self-digest as they are, ethyl acetate, toluol, etc. are generally used. So-called autolysis promoters such as organic solvents and salt are added to induce autolysis. The quality of the yeast extract obtained from such autolysis methods is generally superior to other methods.

Conventionally, when yeast cells are extracted using the autolysis method, a small amount (0.5-5.0%) of an autolysis promoter such as ethyl acetate or toluol is added to the yeast cell slurry. If it is not added, the induction of autolysis will be slow and the extraction will be insufficient. For example, when baker's yeast is autolysed at 45°C for 21 hours and 50 hours, the autolysis rates are low at 15% and 48%, respectively.

As a result of intensive research to develop a method for efficiently promoting autolysis in a short time without using such organic solvents, the present inventor has found that yeast cells with a yeast cell concentration of 5% to 30% have been developed. Add 0.5 sucrose fatty acid ester or sorbitan fatty acid ester to the slurry
The inventors discovered that when the yeast extract is added in an amount of 3.0% to 3.0% for self-digestion, the self-digestion progresses efficiently in a short period of time, and a yeast extract of good quality can be obtained, leading to the completion of the present invention.

The yeast used in the present invention may be any edible yeast belonging to the genus Satucharomyces or Candeida, such as Satucharomyces cerevisiae.
AJ14502, CBC1523, FERM−P5705, CBS1172
Baker's yeast such as Satscharomyces cerevisiae
Examples include brewer's yeast such as CBS1171 and CBS1230, and yeast such as Satucharomyces luxii CBS4632 and Candidauchillus ATCC9226.
As yeast cells, cells obtained by culturing these yeasts in a conventional nutrient medium containing a carbon source, a nitrogen source, and inorganic salts are used. In addition, commercially available baker's yeast (cake) etc. can also be used satisfactorily. When making an extract, prepare a yeast cell slurry with a yeast cell concentration of 5 to 30%. In the case of a yeast cell slurry with a high water content and a yeast cell concentration of 5% or less, the amount of fatty acid ester added for the purpose of autolysis increases, and only a dilute autolysis solution can be obtained. In addition, yeast cell concentration
In the case of a bacterial cell slurry with a high bacterial cell concentration of 30% or more, it is difficult for the fatty acid ester added for the purpose of autolysis to act uniformly on the yeast cells, making it difficult to produce a yeast extract of constant quality. Hateful. In the present invention, for the purpose of autolysis, yeast cell slurry with a yeast cell concentration of 5 to 30% is added to a yeast cell slurry of 0.5% to 3.0%, preferably 0.8% to 2.0%, per yeast cell slurry.
% of sucrose fatty acid ester or sorbitan fatty acid ester alone to induce autolysis. In the present invention, the sucrose fatty acid ester is preferably a monoester, and the fatty acid used is saturated or unsaturated and has a chain length of _C6 to _C22 .
_C8 to _C18 fatty acid esters effectively promote autolysis of yeast cells. Further, the sorbitan fatty acid ester is preferably a monoester, and fatty acids with a saturated or unsaturated chain length of C ₆ to C ₁₄ are used, particularly C ₈
A fatty acid monoester with a chain length of ~ _C12 effectively promotes the autolysis of yeast cells. Regarding the amount of fatty acid ester added to promote autolysis, if less than 0.5% fatty acid ester is added per bacterial cell slurry, the autolysis rate of yeast cells will be low and the reaction will be insufficient to improve the autolysis rate. It is necessary to increase the time. Furthermore, even if 3.0% or more of fatty acid ester is added, the autolysis rate remains unchanged compared to addition of 0.5% to 3.0%. In the present invention, the reaction temperature, reaction time and reaction pH may be carried out in the same manner as conventional methods. That is, the reaction temperature is between 43°C and
In the range of 55℃, reaction time is 20-45 hours, PH is
A good extract will be produced if it is carried out within the range of 5.5 to 6.5. After making the extract, insoluble residues can be removed by centrifugation or the like to obtain a yeast extract. The extract prepared in this manner can be used as is, but for storage purposes, it is desirable to further concentrate it to form a paste with a moisture content of 30 to 60%, or to form it into a powder form by spray drying or the like. The quality of the yeast extract obtained by the method of the present invention is that it has a mellow taste and is of good quality, and can be used as a raw material for various seasonings and foods.

Hereinafter, this will be explained in detail in Examples.

Example 1 A 70-volume jar fermenter was filled with 50 liters of a medium having the composition shown in Table 1 and sterilized at 120° C. for 15 minutes.

Table 1 Medium composition Component Content Glucose 5.0% (NH ₄ ) ₂ SO ₄ 1.0% KH ₂ PO ₄ 0.3% MgSO ₄・7H ₂ O 0.1% CaCl ₂・2H ₂ O 0.05% Corn stave liquor 10ml/ dl PH 5.5 This was inoculated with 200 ml of a seed culture of Satucharomyces cerevisiae AJ14502 (FERM-P5705) obtained by flask shaking culture at 30°C for 18 hours using a medium of the same composition, and the aeration rate was 1/2 V. VM stirring number 500r.
pm, an internal pressure of 0.5 Kg/cm ² , and a temperature of 30° C. for 20 hours with aeration and stirring to obtain a baker's yeast culture solution with a dry bacterial weight of 5.0 g/dl. This culture solution was centrifuged to obtain baker's yeast slurry (17% bacterial cell concentration). Transfer 1,500 g of this baker's yeast slurry to a 2-volume glass container, add 15 g of sorbitan lauric acid monoester (SPAN20(F) (1.0% vs. slurry), and then keep it at 45°C in a constant temperature bath with occasional stirring for 21 hours. Autolysis was performed (autolysis rate 57%).After autolysis, 1.5 ml of water was added, centrifuged, and the resulting supernatant was concentrated under reduced pressure to obtain 326 g of a pasty yeast extract sample with a water content of 53%. (processing yield *60%).

Similarly, use 500g of the above baker's yeast slurry to prepare sorbitan laurate ("Span20(F)").
Autolysis was performed by changing the amount of added and holding at 45% °C for 21 hours to determine the autolysis rate ※※.

The results are shown in Table 2.

Table 2 Sorbitan lauryl ester (SPAN20(F))
Addition effect Added amount (% vs. slurry) Autolysis rate (%) 0 15 0.15 24 0.5 37 0.8 57 1.0 57 1.5 57 3.0 57 *Processing yield (%) = 100 x (dry) solid content in sample / Amount of (dry) bacterial cells used ※※Autolysis rate (%) = 100 × [1 - (dry) bacterial cell concentration after autolysis (%) / (dry) bacterial cell concentration before autolysis (%)] Implementation Example 2 Baker's yeast slurry obtained by the method of Example 1
Add 15 g of sucrose stearate (“DK Ester SS”) to 1500 g (1.0% slurry) and make 45
Autolysis was performed at ℃ for 21 hours (autolysis rate 50%).
The obtained reaction solution was treated in the same manner as in Example 1 to obtain 288 g of a pasty yeast extract sample with a moisture content of 53% (processing yield 53%).

Claims (1)

[Claims] 1. It is characterized by adding sucrose fatty acid ester or sorbitan fatty acid ester to an edible yeast cell slurry with a cell concentration of 5% to 30% at a concentration of 0.5% to 3.0% per cell slurry for autolysis. Method for producing yeast extract.