JPH0459874B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing vinegar using a deep fermentation method. BACKGROUND ART Conventionally, as a method for producing vinegar, a method has been known in which vinegar is produced by a deep fermentation method while a fermentation mixture containing an alcohol-containing raw material solution and vinegar seeds is aerated and stirred in a fermentation tank. In this method, the mash is stirred with a high-speed stirrer and the oxygen-containing gases such as air and oxygen gas passed through the mash are uniformly and finely dispersed in the fermentation tank, so fermentation progresses even inside the liquid. This method has the advantage that the equipment capacity per fixed floor area can be increased compared to the surface fermentation method.
Therefore, in recent years, many methods for producing vinegar have been replaced by deep fermentation methods. By the way, it is desirable for the finished vinegar to have good flavor in order to increase its commercial value, and it has been desired to improve the flavor of vinegar produced by deep fermentation. In order to produce vinegar with good flavor, the surface fermentation method involves increasing the proportion of extract in the mash, which is the raw material for vinegar. However, since the deep fermentation method uses aeration and agitation, it is accompanied by a considerable amount of foaming, and while foaming is constantly eliminated by a mechanical defoamer installed in the head space of the fermentation tank, it is difficult to prevent the foaming from occurring during the fermentation of the raw materials. When the extract content is increased, especially when the extract content is 5% or more, the foaming becomes so intense that the defoamer cannot completely defoamer and the foam overflows from the exhaust hole at the top of the fermentation tank. Since the acetic acid bacteria also flow out of the fermentation tank along with the bubbles, there is a problem that the fermentation of the mash in the fermentation tank stagnates or stops. The purpose of the present invention is to provide a method for producing vinegar with good flavor by suppressing the increase in foaming that occurs when the proportion of extract in the mash of raw materials is increased when producing vinegar using such a deep fermentation method. As a result of various tests, the present inventors have arrived at the present invention. That is, in the method for producing vinegar of the present invention, when producing vinegar by a deep fermentation method while aerating and stirring the mash containing an alcohol-containing raw material liquid and seed vinegar,
It is characterized by adjusting the composition of the mash so that the amino acid content in the mash is about 2.0 or less and the ratio of non-fermentable sugars to fermentable sugars in the extract of the mash is about 0.6 or less. The present invention will be explained in detail below. In the present invention, the alcohol-containing raw material liquid is a liquid containing alcohol consumed by acetic acid bacteria in acetic acid fermentation, and generally an aqueous solution with an acetic acid concentration of 0 to 3% and an alcohol concentration of 4 to 12% is used. For its preparation, alcohol, wort mash, rice mash, wine, and a solution of sake lees are used as alcohol source materials. Further, the seed vinegar is vinegar or mash containing acetic acid bacteria, and it is preferable to use vinegar that is in the period of active fermentation. When preparing mash containing an alcohol-containing raw material liquid and seed vinegar, the mixing ratio of the two and the acetic acid concentration and alcohol concentration of the mash after mixing are not particularly different from those in the conventional case. The mixing ratio of the seed vinegar and the seed vinegar is generally 1 to 5 parts of the seed vinegar to 9 to 5 parts of the alcohol-containing raw material solution, but is not particularly limited. In addition, the acetic acid concentration in moromi is generally 1 to 9.
%, and the alcohol concentration is 3 to 6%. The mash of the present invention contains an alcohol-containing raw material liquid and vinegar seeds, but when preparing the alcohol-containing raw material liquid or preparing the final mash, raw materials other than those mentioned above may be added and used in any proportion as necessary. . That is, raw materials other than those mentioned above include flavor-imparting ingredients such as corn syrup, malt extract, and rice saccharification liquid.
Examples of nutritional substances for acetic acid bacteria include a mixture of glucose, inorganic salts, and yeast extract, and the type and amount thereof may be selected and adjusted depending on the purpose. In the present invention, vinegar is produced from the mash as described above by a deep fermentation method in a fermentation tank with aeration and agitation. Aeration stirring is not particularly different from conventional methods; for example, oxygen-containing gas such as oxygen gas or air is passed through a vent pipe and, if necessary, a pump is used to pump the gas at a rate of 0.03 to 0.2 vvm (ventilation volume/liquid volume/per unit). This is fed to the lower part of the mash at an aeration rate of 50 min), and is stirred and dispersed using a turbo or turbine stirrer to maintain the dissolved oxygen concentration in the mash at 1 to 8 ppm. As for the agitator, a turbo type is preferable to a turbine type, especially when the capacity of the tank is large, because it has good ventilation efficiency and requires a small amount of ventilation. In addition, as a fermentation method, the degree of continuous
There are various methods depending on whether it is adopted or not, such as a batch method, a semi-continuous method that repeats the process continuously, and even a continuous method.
There are no particular restrictions. The fermentation temperature and time are not particularly different from conventional fermentation, for example, at 26 to 38℃.
The fermentation process is carried out for about 20 hours to a week, and the fermentation is completed when the alcohol concentration in the mash has decreased to about 0.5 to 0.1%. Note that it is no different from conventional methods to replenish alcohol as necessary during fermentation. In the present invention, when producing vinegar in this way, the amino acid content in the mash is approximately 2.0 or less, and the ratio of non-fermentable sugars to fermentable sugars in the extract (hereinafter this ratio is referred to as the NS/FS ratio). ) is approximately 0.6
The major feature is that the composition of the mash is adjusted as shown below. Batch and semi-continuous methods usually require some time to mix the alcohol-containing raw material liquid and seed vinegar, but the length of this time and the start and end of fermentation immediately after mixing may vary during the mashing process. The amino acid content and the NS/FS ratio of are virtually unchanged. Therefore, when adjusting the above numerical values, in the case of batch type and semi-continuous type, the proportion of the alcohol-containing raw material liquid is determined so that the numerical value range is reached when the alcohol-containing raw material liquid and the vinegar seed are mixed. You can do this depending on the situation. In addition, in the case of a continuous type, the alcohol-containing raw material liquid is constantly mixed with the seed vinegar, so mix the alcohol-containing raw material liquid so that the mash in any part of the fermenter falls within the above numerical range. All you have to do is decide. The reason why the amino acid content in the mash is kept below about 2.0 in the present invention is that it depends on the ratio of non-fermentable sugars to fermentable sugars in the extract, but if it is higher than this value, foaming will be suppressed by the defoaming machine. This is because the effect is substantially eliminated, and preferably the amino acid content in the mash is about 1.5 or less from the viewpoint of the foaming suppressing effect. In the present invention, the amino acid content is one of the indicators indicating the content ratio of amino nitrogen, and is calculated as follows using the Seelenzen formol titration method. Take 10 ml of the sample (mash), neutralize it with normal sodium hydroxide solution, and add 5 ml of neutral formalin solution to this.
After addition, neutralization titration is performed with N/10 sodium hydroxide solution having a titer of F. If this titration ml number is a, then amino acid content = a x F.Also, the reason why the NS/FS ratio in the extract should be approximately 0.6 or less depends on the amino acid content in the mash mentioned above, but if it is higher than this value, This is because the foaming suppression effect is virtually eliminated, and it is preferable to reduce the NS/FS ratio.
It is desirable to set it to 0.4 or less. Here, the extract component refers to the evaporation residue of the mash such as carbohydrates and proteins. Fermentable sugars refer to sugars that are digested by alcohol-fermenting yeast among all soluble sugars including starch and dextrin, and include, for example, glucose, fructose, maltose, sucrose, and maltotriose. In addition, non-fermentable sugars refer to sugars that are not digested by alcohol-fermenting yeast among all sugars including starch and dextrin, such as galactose, trehalose,
Examples include maltotetraose and dextrin. Note that the method for adjusting the composition of the mash is not particularly different from conventional methods, and any method can be used. In order to adjust the composition of mash to the above numerical range, measure the amino acid content and the content of fermentable sugar and non-fermentable sugar in each raw material to be used, and make sure that the composition of mash after mixing all raw materials falls within that numerical range. All you have to do is make it look like this. As an example, we will show an example of adjusting the alcohol-containing raw material liquid in a normal case when 1 to 30% of seed vinegar is used in the mash. Although these values are not fixed, (1) Rice saccharified liquid 20 to 60 , malt extract 1-13Kg, sake lees solution 3-8, denatured alcohol 10-20,
Shimizu 25-45, (2) Corn saccharification liquid 15-25, Wort mash 10-50
, Sake lees solution 3~8, Denatured alcohol 10~
20, Shimizu 20-50 (3) Rice mash 8-15, Concentrated rice saccharification liquid 10-15,
Sake lees solution 3-25, denatured alcohol 8-15
, Shimizu 30-70, etc. According to the present invention, although the mechanism of action is not necessarily clear, as described above, the amino acid content in the mash is about 2.0 or less, and the NS/FS ratio in the extract of the mash is about 0.6 or less. By adjusting the composition of the mash, the increase in foaming that occurs when the proportion of extract in the mash is large can be suppressed, resulting in acetic acid bacteria flowing out of the fermentation tank along with the foam, resulting in stagnation of the fermentation process. Since problems such as stoppage can be solved, vinegar with good flavor can be produced. Test examples showing the effects of the present invention and Examples of the present invention will be described below using a batch method as an example. In addition, in the present invention, % refers to weight/for extract content and acetic acid.
Volume % is indicated, and for alcohols volume/volume % is indicated. Test example A 20-capacity aeration stirrer (rotation speed: 500 rpm, tank height: 44 cm) was filled with 10 of the 14 types of alcohol-containing raw material solutions shown in Table 1 below, each having a different composition. , alcohol concentration 1
%) 2, air flow rate 0.1vvm, temperature 32
Batch fermentation was carried out at ℃. For reference, the foaming state during fermentation, the average acetylation rate, and the flavor of the product after fermentation were observed and measured, and the results are shown in Table 1 below. As is clear from the table, in the cases of Test Nos. 1, 2, 3, 4, 6, 7, 8, 11, and 12, which fall within the scope of the present invention, bubbles overflowed from the exhaust hole at the top of the fermentation tank. In addition, in order to suppress foam, the amino acid content is approximately 1.5 or less, allowing fermentation to proceed smoothly.
Test Nos. 1, 2, 6, with an NS/FS ratio of approximately 0.4 or less;
It is understood that cases 11 and 12 are more preferable.

【table】

[Table] Example 1 20,000 ml of alcohol-containing raw material liquid with the following blending ratio was added to a 30,000-capacity aeration stirring device (with turbo stirrer, rotation speed: 1,450 rpm, tank height: 450 cm, with a blade attached to the top of the tank for removing bubbles). This contains 2,000 seeds of vinegar (a fermented mash of alcoholic vinegar with an acetic acid concentration of 6% and an alcohol concentration of 1%) at a rate of approximately 30% per minute.
Batch fermentation was carried out at a temperature of 32°C with an aeration rate of 0.08vvm. 42 hours after the start of fermentation, the acetic acid concentration reached 7.2% and the alcohol concentration reached 0.2%, so fermentation was terminated.
Vinegar with good flavor was obtained without overflowing from the exhaust hole at the top of the tank. Mixing ratio of alcohol-containing raw material liquid Rice mash 20 Rice saccharification liquid (amazake) 20 Sake lees solution 5 Denatured alcohol 7 Alcoholic vinegar (acetic acid concentration 6.8%) (alcohol concentration
0.2%) 10 Shimizu 38 Extract content of mash components at the start of fermentation 6.5% Amino acid content 1.13 NS/FS ratio 0.06 Acetic acid concentration 1.6% Alcohol concentration 6.4% Example 2 In Example 1, the blending ratio of alcohol-containing raw material liquid Fermentation was carried out under the same conditions as in Example 1, except that the amount of the raw material was changed to 18,000 ml of alcohol-containing raw material liquid and 3,600 ml of vinegar seed. 44 hours after the start of fermentation, the acetic acid concentration reached 7.6% and the alcohol concentration reached 0.2%, so fermentation was terminated, but during this time, bubbles did not overflow from the exhaust hole at the top of the tank, and vinegar with good flavor was obtained. . Mixing ratio of alcohol-containing raw material liquid Corn syrup 20Kg Malt extract 7Kg Ring juice 20 Denatured alcohol 15 Fresh water 40 Extract content of mash components at the start of fermentation 18.5% Amino acid content 0.77 NS/FS ratio 0.4 Acetic acid concentration 1.8% Alcohol concentration 6.1% Implementation Example 3 In Example 1, the blending ratio of the alcohol-containing raw material liquid was changed to the following, and the acetic acid concentration of the seed vinegar was changed to 11.
Fermentation was carried out under the same conditions as in Example 1, except that the fermentation mash was changed to alcoholic vinegar with an alcohol concentration of 1%. 84 hours after the start of fermentation, the acetic acid concentration reached 11.8% and the alcohol concentration reached 0.2%, so fermentation was terminated, but during this time, bubbles did not overflow from the exhaust hole at the top of the tank, and vinegar with good flavor was obtained. . Mixing ratio of alcohol-containing raw material liquid Rice mash 30 Concentrated rice saccharification liquid 14 Alcohol vinegar (acetic acid concentration 12%, alcohol concentration
0.2%） 56 Extract of mash components at the start of fermentation 8.2% Amino acid content 0.95 NS/FS ratio 0.06 Acetic acid concentration 7.1% Alcohol concentration 5.0%

Claims (1)

[Scope of Claims] 1. When producing vinegar by the deep fermentation method while aerating and stirring the mash containing an alcohol-containing raw material liquid and seed vinegar, the amino acid content in the mash is approximately 2.0 or less and the fermentation in the extract of the mash is performed. 1. A method for producing vinegar, which comprises adjusting the composition of mash so that the ratio of non-fermentable sugar to fermentable sugar is about 0.6 or less. 2. The method for producing vinegar according to claim 1, wherein the extract content in the mash is about 5% or more. 3. The composition of the mash is adjusted so that the amino acid content in the mash is about 1.5 or less, and the ratio of non-fermentable sugar to fermentable sugar in the extract of the mash is about 0.4 or less. The method for producing vinegar described.