JPS602181A - Preparation of raw sake - Google Patents

Abstract

PURPOSE:To obtain raw SAKE having superior quality of GENSHU (SAKE after brewing, not blended with other ingredients) of its own, distributable at normal temperature, less expensively, by filtering unheated ENSHU with a capillary polysulfone ultrafilter ultrafilter having specific properties. CONSTITUTION:A polysulfone resin having a repeating unit shown by the formula in the main chain of the molecule is dissolved in a solvent such as dimethylformamide, etc., made into a film by wet film forming process, etc., to prepare a capillary ultrafilter having 10-60wt% stopping ratio of dextran having 70,000mol.wt. and >=80wt% stopping ratio of dextran having 500,000mol.wt., 0.5-2m/m inner diameter and 0.1-1m/m thickness. A great number of the film are bundled, sealed with a resin at both end parts to prepare an inner-pressure filtration module, and unheated GENSHU is filtered with the module, to give the desired raw SAKE distributable at normal temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing raw sake that can be distributed at room temperature. Namazake here refers to sake that is not pasteurized at all in the manufacturing process for the purpose of sterilization and termination of fermentation. During the manufacturing process of sake, the raw sake is generally pasteurized, but during this process, protein turbid substances come together, producing a turbid substance called white flake.

In order to remove this whitishness, a process is performed, but if the ultrafiltration method can be used to sterilize and remove protein-turbid substances, it is possible to produce raw sake that retains the unique flavor of the original sake. be. The inventors of the present invention have conducted extensive studies for this purpose and have come up with the present invention. Several studies have already been carried out regarding ultrafiltration treatment of sake. For example, in the filtration of raw sake, certain types of membranes do not have the effect of preventing whitening, and some membrane types have the potential to alter the quality of sake (for example, Sato et al., Fermentation Engineering, Vol. 55, 84-94, 1977), and a stable film that is effective in preventing white flaking has also been discovered (
0hba, T, etal, J, Brew, So
c, Japan, Vo173, p951-954.
1978). However, to date, there have been no reports of actual use of ultrafiltration to produce raw sake that can be distributed at room temperature.

The present inventors believe that a membrane that has a high p-retardation efficiency and is easy to handle can be practically used for such purposes,
A capillary-like separation membrane was created using polysulfone resin, and the filtration of raw sake was investigated. Capillary-shaped filtration membranes 1) can perform cross-flow filtration, 2) increase the liquid flow rate to prevent scale build-up on the membrane surface, and 3) are easy to clean because there are few stagnant parts. It has been recognized that it has advantages such as being able to minimize the impact on the reeds and unprocessed sake, and 4) lowering the initial cost of the device due to the high packing density of the membrane, making it the easiest filtration membrane to handle in practice. . In a capillary-like filtration membrane, the smaller the inner diameter, the higher the packing density, but the greater the pressure loss and the lower the filtration efficiency.

Moreover, if the inner diameter is large, the pressure loss will be small, but the pressure resistance of the membrane will be reduced, and the load on the pump to maintain a constant flow rate will be increased. In addition, if the molecular weight fraction is small, the inhibition of cloudy matrix substances will be complete, but it will lower the ν hypermobility and have a negative effect on the flavor and aroma of raw sake, and if it is large, the inhibition of cloudy matrix substances will be incomplete. Become. In order to obtain a capillary-like filtration membrane with the best balance of these conditions, the present inventors have determined that the rejection rate of dextran having a molecular weight of 7 QOOO is 10 to 60 Q, preferably 251% to 35 Q.
6 or less, the rejection rate of dextran having a molecular weight of 50QOOO is 80% or more, preferably 90%, and the inner diameter is 0.5 to 2%, the wall thickness is 0.1 to 1.0%, and preferably the inner diameter is 1. We have discovered that by filtering raw sake that has not been pasteurized through a capillary polysulfone filtration membrane with a thickness of 0.0% and a wall thickness of 0.3%, it is possible to produce raw sake that can be distributed at room temperature. Note that dextran is a type of polysaccharide and has a molecular weight of 70. OOO and U: Pharmacia's T-70 and T-500 were used as 50QOOO, respectively. The rejection rate was measured by filtering a 0.5% aqueous solution of dextran at a filtration pressure of 0.6 kr/cf7N and calculating it using the following formula.

Ci where R is the rejection rate @), Ci and Cp are the dextran concentrations of the stock solution and filtrate, respectively. In addition, polysulfone resin contains a structure that becomes a repeating unit in the main chain of the molecule, and in the following explanation, UDEL P 17 manufactured by UCC Co., Ltd.
00 is used, but it is not limited to this.

The present invention will be explained below with reference to Examples.

A capillary-like filtration membrane having the shape and dextran rejection rate shown in Table 1 was formed by a normal wet membrane forming method, and the membrane area was 2.5 d and the effective length was 100 cm.
A module with this was created, and the unprocessed sake before pasteurization was filtered through internal pressure filtration.

The filtration rate is inlet pressure 3 kv/ad, unprocessed sake flow rate 1.
The average filtration speed is shown when concentration filtration is performed up to a concentration ratio of 20 times under the filtration condition of 5 m/sec. The distribution test was conducted by observing the appearance of white flakes when the product was transported back and forth between Tokyo and Osaka in a regular truck during the height of summer. In addition, the storage test was to observe the occurrence of white blur when stored in an environment of 20° C. or higher for 18 months.

In Experimental Examples 6 and 7, which are examples of the present invention, there was no occurrence of white blur in distribution tests and storage tests, and the operability and workability during filtration were also good. T-70 blocking rate is 40%, T
In Experimental Examples 1 to 3, in which the rejection rate of -500 was 95, no white flaking was observed in each test, but since the inner diameter or wall thickness was outside the scope of the present invention, The drivability, workability, etc. were poor. Further, in Experimental Examples 4 and 5, white blurring was observed in the distribution test or the storage test, and the object of the present invention could not be achieved.

Procedural amendment (voluntary) September 1, 1980' Commissioner of the Japan Patent Office1, Indication of the case, 1982 Patent Application No. 1077642, Name of the invention, Process for producing raw sake3, Person making the amendment, Relationship with the case Patent applicant address: 1-2-2-4 Uchisaiwai-cho, Chiyoda-ku, Tokyo. Full text of the specification subject to amendment.

Description 1, Title of the invention: Method for producing raw sake 2, Claims: Molecular weight 7: Rejection rate of QOOO dextran is 10 or more 6
0% or less, the rejection rate of dextran with a molecular weight of 50QOOO is 80q6 or more, and the inner diameter is 0.5 to 2.0%.
Method 3 for producing unpasteurized sake that can be distributed at room temperature, characterized by passing raw sake that is not pasteurized through a capillary-shaped polysulfone ultrafiltration membrane without a support and having a wall thickness of 0.1 to 1.0%. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing raw sake that can be distributed at room temperature. ζ Here, raw sake refers to sake that is not subjected to any heat treatment for the purpose of sterilization and termination of fermentation during the manufacturing process up to shipment. In the manufacturing process of sake, the mash obtained through aging and fermentation is filtered through an upper tank to obtain raw sake, which has a unique aromatic aroma and is of excellent quality. However, due to the presence of koji bacteria and hiochi bacteria, it is extremely susceptible to deterioration and the quality of sake is likely to be impaired. For this reason, despite its excellent quality, raw sake cannot be supplied to consumers through normal distribution channels, and by keeping it at a slightly low temperature, it can only be used for a short period of time in extremely limited areas. supply was possible. The purpose of the present invention is to invent a method for producing Namazake that allows such delicate Namazake to be constantly distributed at room temperature and to be widely available on the market.

Traditionally, sake undergoes a sedimentation process called orihiki, and after primary filtration with the addition of activated carbon, it undergoes a pasteurization process for the purpose of sterilization. Pasteurization stops fermentation and sterilizes hiochi bacteria, stabilizing the quality of sake.
At the same time, the rich aroma of raw sake is lost. After pasteurization, the unprocessed sake is filtered by adding gelatin and persimmon juice to prevent so-called white blur caused by associative proteins, and then subjected to the necessary treatments, and further heated and sterilized before shipping to become a product. It is something. In this conventional method of producing sake, it is obvious that the aroma of raw sake is lost during the pasteurization process, and if the pasteurization process is omitted to preserve the aroma, it is unlikely that deterioration due to hiochi bacteria will occur. It is clear from experience. The present inventors thought that by adopting the ultrafiltration method, which has seen rapid development in recent years, to the sake manufacturing process, it would be possible to produce raw sake that retains its aroma and does not cause deterioration. Several studies have already been conducted on ultra-flow filtration of sake, but these studies have focused on the prevention effect of white flakes caused by protein-based turbid substances, and it has been found that some film types have a prevention effect. has also been reported. However, no studies have been conducted on the deterioration of raw sake caused by Hiotoshi bacteria, and the absence of Hiotchi bacteria in filtered Namazake has not been confirmed.

In addition, there are no clear restrictions on film types with regard to the effect of preventing white embedding, and there have been no reports of practical use of such a method.

The present inventors believe that a membrane with high flow efficiency and easy handling can be practically used for such purposes,
A capillary-like separation membrane was created using polysulfone resin, and the filtration of raw sake was investigated. The polysulfone resin film has good chemical resistance, and it has been confirmed that even when actually immersed in raw sake, it does not impart any off-odor or chemical odor to the raw sake.

Capillary-shaped filtration membranes have the following advantages: 1) cross-flow filtration is possible, and 2) the liquid flow rate can be increased, so there is less scalability on the membrane surface.
3) It is easy to clean because there are few stagnation parts, and the influence on the raw beer can be minimized. 4) The initial cost of the equipment is low because the membrane is packed densely. It is recognized for its advantages and is the easiest filtration membrane to use in practice. In a capillary-like filtration membrane, the smaller the inner diameter, the higher the packing density, but the greater the pressure loss, the lower the filtration efficiency.

Moreover, if the inner diameter is large, the pressure loss is reduced, but the pressure resistance of the membrane is reduced and the load on the pump for maintaining a constant flow rate is increased.

Taking these points into consideration, the inventors created and tested polysulfone capillary-like membranes of various shapes.
．． It has been found that a shape with an inner diameter of 1% and a wall thickness of 0.3% is most efficient. Regarding the molecular weight cutoff of the membrane, it has been found that if it is too large, the inhibition of turbid substances and fungi will be incomplete, and if it is too small, it will not have a negative effect on the flavor and aroma of raw sake, and the present inventors have determined that these conditions We conducted studies to obtain the most balanced capillary-like filtration membrane with a molecular weight of 7.
The rejection rate of QOOO dextran is 10% or more and 60% or less, preferably 25% or more and 35% or less, and the rejection rate of dextran with a molecular weight of 500,000 is 80% or more,
It has been found that by filtering raw sake that is not pasteurized through a capillary polysulfone filtration membrane, which preferably has a content of 90% or more, it is possible to produce raw sake that can be distributed at room temperature. Note that dextran is a type of polysaccharide and has a molecular weight of 70.0.
Pharmacia's T-70 and T-500 were used as 00 and 500.000, respectively. In addition, the rejection rate was measured by adding a 0.5% aqueous solution of dextran to 0.6%.
It was filtered at a filtration pressure of /i, and calculated according to the following formula.

Ci where R is the rejection rate @), Ci and Cp are the dextrin 270 degrees of the stock solution and filtrate, respectively. In addition, polysulfone resin contains a structure that becomes a repeating unit in the main chain of the molecule, and in the following explanation, UDELP 170 manufactured by UCC Co., Ltd.
Although 0 is used, it is not limited to this.

The present invention will be explained below with reference to Examples.

Example I UDELP 1700 14% in dimethylformamide
The solution was dissolved in a concentration of 1.0% by weight, and this solution was used as a film-forming stock solution at a predetermined temperature using a double-structure nozzle for wet film-forming. A membrane was formed. 100 of these membranes were bundled and both ends were sealed with resin to create an internal pressure filtration module with a length of 50 crrL. When the rejection rate of dextran T-70 and T-500 was measured using this module,
They were 32 and 95 inches, respectively. This module was used to filter raw sake without pasteurization. Filtration conditions are temperature 10-15℃, average filtration pressure 4.5k7/
The filtration rate was 45 t/hr. When a viable bacteria culture test was conducted on the filtration pond obtained by filtration, the number of viable bacteria was 0, and no other viable bacteria such as Hiobacterium was observed. First analysis of raw sake and filtration pond analysis test results
Shown in the table. No change in alcohol quality was observed.

In addition, the results of a sensory test conducted by a panel showed that the filtration pond retained the aroma of raw sake, giving good results. Pack the filter into a sterilized glass bottle and keep it at a temperature of 20-25℃ for 12 months.
Although it was stored at a temperature of 25 to 32°C for 6 months, no change in alcohol quality, generation of turbidity, or change in texture was observed. In addition, the filtration pond was transported back and forth between Tokyo and Osaka by regular truck during the summer, but no adverse effects were observed. Also, the condition of the filtration basin was good.

Table 1 Analysis Results Example 2 Separation membranes of the same shape were produced by the same operations as in Example 1, but with different membrane forming temperatures. This was made into a module using the same procedure, and the inhibition rates of dextran T-70 and T-500 were measured to be 26 and 85, respectively. The same raw sake as in Example 1 was filtered under the same conditions to obtain a filter basin. The filtration rate was 52 t/d·hr.

Filtration pond obtained in this way (alcohol concentration 20.4 degrees)
was diluted to an alcohol concentration of 15.7 degrees by adding water filtered through the same module. The filter pond thus obtained was subjected to a culture test to determine the number of viable bacteria, but the number of viable bacteria was 0. In addition, a storage test and a distribution test were conducted in the same manner as in Example 1, but no abnormalities were observed.

Claims (1)

[Claims] The inhibition rate of molecule 17QOOO dextran is 10- or more6
0% or less, the rejection rate of dextran with a molecular weight of 500,000 is 80% or more, and the inner diameter is 0.5 to 2.0%.
, a method for producing unpasteurized sake that can be distributed at room temperature, characterized by filtering raw sake that is not pasteurized through a capillary-shaped polysulfone ultrafiltration membrane without a support and having a wall thickness of 01 to 10%.