JPH0552184B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement in the method for producing solid koji using a puffed raw material obtained by extruder treatment,
By mixing and coating the puffed raw material obtained by extruder treatment with an appropriate amount of powder such as finely ground wheat, cracked roasted wheat, etc., the stickiness (stickiness) of the puffed raw material is prevented. This invention relates to a method for producing solid koji that makes it easy to make koji, has very few bacteria, and produces high-quality koji that has a high titer of enzymes such as protease. Conventionally, a mixture of protein raw materials such as defatted soybeans and carbohydrate raw materials such as wheat is kneaded under heat and pressure in an extruder, and then rapidly released under low pressure to cause expansion, thereby obtaining expanded raw materials for koji making. Are known. However, this puffed raw material is different from the puffed raw material obtained by heating under pressure with saturated steam etc. in a hollow airtight container and then rapidly releasing it under lower pressure.In order to facilitate the growth of koji mold, this puffed raw material is sprinkled with water as needed to make it absorb water. If you let
Since the surface of the puffed raw material becomes highly sticky,
The seed koji or koji mold spores cannot be uniformly spread, they are easily contaminated by miscellaneous bacteria, and they tend to adhere to each other and form clumps, making it impossible to accurately control the temperature of the koji product in this area, which hinders the growth of koji mold. It is difficult to obtain high-quality koji, and it adheres to the koji making equipment such as the filling machine, handling machine, and koji making tank (kasten), making it difficult to remove it later. It has its drawbacks. The present invention was completed as a result of various studies to solve these drawbacks in the method for producing solid koji. ,
A method for producing solid koji, which is characterized in that when solid koji is produced by rapidly discharging it under low pressure to cause it to expand, and using the obtained puffed raw material, the puffed raw material is mixed and coated with an appropriate amount of powder. be. The present invention will be explained in detail below. First, the protein raw materials used in the present invention include one or more kinds of whole soybeans, defatted soybeans (defatted processed soybeans), etc., which are commonly used in the production of soy sauce, miso, etc. Examples of the carbohydrate raw materials include one or more of wheat, barley, corn, rice, coriander, various starches, etc. used in the production of soy sauce, miso, sake, shochu, and the like. Next, as the extruder used in the present invention, either a single-screw type or a twin-screw type may be used, but in a twin-screw extruder, the raw material generates heat due to shearing between the barrel and the screw. This is preferable because the temperature of the raw material can be accurately controlled using a heater or the like from the outer peripheral wall of the barrel, and the raw material can be appropriately denatured. Next, to carry out the present invention, the above-mentioned protein raw material and carbohydrate raw material are supplied to the feed port of the extruder and kneaded under heat and pressure. At this time, water is simultaneously supplied to the feed port (supply port) or into the barrel through a communicating pipe. The water is
It may be added in an amount of 5 to 65%, preferably 20 to 28% of the total raw materials. If the water content is less than 5%, it will be difficult to uniformly heat and denature the raw material, it will easily burn, and it will be difficult to continuously extrude and knead. On the other hand, if the amount is more than 65%, the solid content in the raw material will be diluted and a soft noodle-like extrudate will be obtained, but it will become sticky after extrusion and will tend to stick together, resulting in flakes, etc. It becomes difficult to cut and granulate. The temperature of the raw material inside the extruder barrel is
Set at 40~200℃, preferably 120~130℃, and the pressure inside the barrel is 10~100Kg/ ^cm2 , preferably 40℃.
-60 Kg/cm ² , and the amount of raw material supplied is adjusted so that the substantial residence time in the heating barrel section is usually 3 to 120 seconds, preferably 5 to 60 seconds. If the temperature in the barrel described above is lower than 40°C, a later heat treatment will be required again. Furthermore, if the temperature inside the barrel is higher than 200°C, it is not preferable because it tends to cause scorching. Also, the residence time is
It is preferable to lengthen the time when the temperature is low, and conversely shorten the time when the temperature is high. Next, by satisfying the conditions of moisture, pressure, temperature, and time, the raw materials that have been kneaded under heat and pressure in the barrel can be continuously compressed under lower pressure, such as atmospheric pressure. can do. The raw material extruded from the die is in the shape of noodle strings or strips, but in order to make it easier to make koji, it is cut into strips or granulated. In this case, it is preferable to cut or granulate so that the bulk specific gravity [ratio of weight (Kg) to constant volume ()] is 0.25 to 0.45. In other words, the bulk specific gravity is
If it is smaller than 0.25, the surface area per raw material will be small and it will be difficult to obtain koji with high enzyme titer.On the other hand, if it is larger than 0.45, fine particles will be produced. It becomes difficult to allow air to flow smoothly, to always easily and uniformly control the temperature of the koji layer as desired, and to smoothly eliminate harmful gases within the koji layer, making it difficult to obtain good koji. In order to facilitate the propagation of koji mold, the puffed raw material obtained in this way can be used as is, dried, or added with water to reduce the moisture content to 25 to 65%, preferably 37 to 47%.
After adjusting the amount, mix and coat an appropriate amount of powder. In the present invention, it is extremely important to add this powder, and as mentioned at the beginning, the puffed raw material whose moisture content is adjusted to 25 to 65% has very strong stickiness, so it has various drawbacks. invite. On the other hand, when an appropriate amount of powder is mixed and coated, the surface of the puffed raw material becomes smooth, which makes it easy to uniformly spread the seed koji or koji mold spores, and also allows the mutual bonding of the raw materials. prevents wear and tear,
Temperature-controlled and humidity-controlled air can be circulated smoothly, and the temperature of the koji layer can always be easily and uniformly adjusted as desired. Also, harmful gases in the koji layer can be smoothly removed, making it possible to eliminate miscellaneous Koji with very few bacteria and high enzyme titer can be obtained. In addition, since there is less adhesion of the puffed raw material to the filling machine, handling machine, koji making tank, etc., it becomes easier to manage the cleaning of these koji making equipment. Next, as the powdered material in the present invention, the above-mentioned carbohydrate raw material is dried and pulverized, roasted and crushed, or powdered carbohydrate raw material processed without an extruder, such as starch, and carbohydrate raw material. Powdered materials obtained by extruder treatment, such as those obtained by swelling the protein material alone or in combination with a protein raw material using an extruder, drying it, and then pulverizing it, can be mentioned. These are preferably ground to a particle size of the same level or finer than that of roasted cracked wheat used in soy sauce brewing, for example, about 28 mesh (mesh opening 0.59 m/m). It is preferable to add as little powder as possible, but in order to effectively prevent the stickiness of the puffed material, it should be added at least 3% by weight, especially from 10 to 20% is preferred.
In addition, if the amount of powdered material to be added is large, adjust the amount of protein raw material and carbohydrate raw material used in advance when preparing the puffed raw material with an extruder.
It is preferable not to impair the relative blending balance of protein raw materials and carbohydrate raw materials (for example, in the case of soy sauce, the blending balance is approximately 1:1) of the target food. Next, after mixing and coating the puffed raw material with an appropriate amount of powder, a filamentous fungus such as Aspergillus or the like is inoculated, and the culture environment is suitable for the growth of the bacteria used, for example, at a temperature of 25°C.
Indoor mycelium at ~35℃ and 90-100% humidity,
or the time required for a sufficient number of spores to settle;
For example, culture for 30 to 80 hours. The above-mentioned filamentous fungi are not limited, and include, for example, those for brewed foods such as soy sauce and miso, those for seed koji,
Microorganisms can be selected and used depending on the purpose of the solid koji, such as for enzyme production. For example, Aspergillus soya, Aspergillus oryzae,
Examples include Aspergillus tamari and Aspergillus niger. In this manner, according to the present invention, high-quality koji can be obtained that has very few undesirable bacteria (live bacteria) and has very high enzyme titers such as protease and amylase. Hereinafter, the present invention will be specifically explained with reference to Examples. In this example, the number of viable bacteria and protease activity of the solid koji obtained were measured by the following method. (1) Measurement of the number of viable bacteria By the plate method using a sweetened bouillon agar medium,
The number of colonies was determined after culturing at 35°C for 48 hours. (2) Measurement of protease activity Measurement was performed by the Anson-Hagiwara method using milk casein (PH7.0) as a substrate. Example 1 Defatted processed soybeans and wheat were mixed to have the raw material composition listed in Table 1, and fed through a feeder to a twin-screw extruder, while adding water (moisture 26%) at a pressure of 50 Kg/cm ² , product temperature 128℃, residence time 25
The mixture was kneaded under heat and pressure for a few seconds, extruded into noodle strings under normal pressure, cut with a propeller cutter, and dried to form a cylindrical shape with a diameter of about 4 mm and a thickness of 3 mm, with a bulk specific gravity of about 0.4. A puffed raw material was obtained. Next, the charged moisture is added to the puffed raw material in the first place.
Water was uniformly sprinkled in a screw container to obtain the values shown in the table. It was observed that the surface of the material after water sprinkling and water absorption was quite sticky. Next, the puffed wheat obtained by previously treating wheat with an extruder under the same conditions as above is dried, and the obtained fine powder wheat (moisture 6
%, passed through a 32-mesh sieve) to the proportions listed in Table 1, inoculated with soy sauce starter koji, and subjected to cross-ventilation koji production at a temperature of 28°C according to a conventional method. Koji (soy sauce malt) was obtained. For comparison, a control solid koji was obtained by performing the same process as above except that finely powdered wheat was not added. When the number of viable bacteria and protease activity of the solid koji thus obtained were measured, the results shown in Table 1 were obtained.

[Table] From the above results, in the control area where the amount of powdery material added was 0%, the packed raw materials after watering were quite sticky in all categories, and the granulated and expanded raw materials were bound to each other. However, it was found that in the category of the present invention in which powdery material was added, the loaded material did not become very sticky after watering, and especially in the category in which 30% or more was added, it was found that it was hardly sticky. In addition, from the results in Table 1, the control koji to which no powder was added was severely contaminated with bacteria in the moisture content range of 42 to 47%, and protease activity was observed to be very low. It can be seen that the koji of the present invention to which the compound has been added has little bacterial contamination in the moisture content range of 37 to 47%, and exhibits very high protease activity.

Claims (1)

[Claims] 1. In producing solid koji using the obtained expanded raw materials obtained by kneading protein raw materials and carbohydrate raw materials under heat and pressure in an extruder, and then rapidly releasing them under low pressure to cause expansion. A method for producing solid koji, which comprises mixing and coating the expanded raw material with an appropriate amount of powder. 2. The method for producing solid koji according to claim 1, wherein the powder is at least one selected from the group consisting of dry and pulverized carbohydrate raw materials, starch, and dry and pulverized materials for puffing.