KR20150124411A - Method for producing Chunggukjang with increased quality and preference and Chunggukjang produced by the same method - Google Patents

Abstract

The present invention relates to a method for preparing fermented soybeans, the fermented soybeans prepared by using the method, a processed food product using the fermented soybeans, and Bacillus subtilis SCKB1319 strains (KCCM 11684P) having biogenic amine decomposition activity and glutamic acid-producing ability. The method includes the following steps: (a) removing water from soaked soybeans (Glycine max), boiling the soybeans, and cooling the soybeans at 55-65°C; and (b) inoculating the Bacillus subtilis to the soybeans cooled in the step (a) and fermenting the soybeans at 35-45°C.

Description

[0001] The present invention relates to a method of manufacturing a cheonggukjang having enhanced quality and preference, and a method of producing chunggukjang prepared by the above method,

The present invention relates to a process for producing soybean milk, comprising the steps of: (a) removing water from soaked soybeans, heating and cooling to 55 to 65 ° C; And (b) inoculating Bacillus subtilis to the cooled soybeans of step (a) and fermenting the fermented soybeans at 35 to 45 ° C. the soybean processed food and with biogenic amines processing the soybean prepared in (biogenic amine) decomposing activity, and Bacillus having the glutamic acid-producing ability subtilis (Bacillus subtilis strain SCKB1319 (KCCM 11684P).

Chongkukjang, a traditional soybean fermented food, contains dietary fiber, phospholipid, isoflavone, phenolinic acid, saponin, trypsin inhibitor and phytic acid as well as nutrients such as proteins, carbohydrates and fats derived from soybeans, and contains vitamins, minerals, Essential amino acids and other necessary nutrients and active ingredients. Chongkukjang's effects known so far include low blood cholesterol, prevention of hypertension, anticancer, antioxidant, thrombolysis, prevention of osteoporosis, and improvement of liver function.

On the other hand, the fermentation of Chongkukjang is greatly influenced by the kind of soybean, strain used, fermentation temperature and humidity. Due to the use of microorganisms, the distinctive flavor due to differences in fermentation conditions has become a factor that greatly affects the quality of Chungkookjang.

Conventionally, the soybean is produced by washing soybeans, boiling them in hot water, boiling yeast germs and Bacillus subtilis, sealing them in a sealed container and fermenting them. However, due to changes in diet and westernization of residential culture, the consumption of Chungkookjang is gradually decreasing. In the course of fermentation of soybean, the unpleasant odor is generated due to the fermentation of the moisture permeated in the soybean life, Although the distinctive odor that occurs during the process is rich in nutrition and benefits the human body, there has been a problem that the degree of preference for children and young people is limited and is limited to popularization. As the conventional technology for improving the palatability and quality of Cheonggukjang, there have been reported herbaceous herbs such as herb medicine added with medicinal plants or natural materials, red ginseng chonggukjang, green tea chonggukjang, chitosan chonggukjang, but the study on the quality and sensual characteristics In Korea, there are few companies that produce Chongkukjang by standardized manufacturing process.

On the other hand, biogenic amines are nitrogen compounds which are produced mainly by chemical action such as decarboxylation action of an amino acid, amino group transfer action, etc., and are generated by microorganisms or biochemical activities in a protein-containing food. Biogenic amines in being formed by amino dicarboxylic decarboxylase (amino acid decarboxylase) action of microorganisms bacteria arc Pseudomonas (Acromonas), Bacillus (Bacillus), bakteo (Citrobacter), Clostridium (Clostridium) in a sheet, Escherichia (Escherichia), keurep when it is known as having a Ella (Klebsiela), Lactobacillus bacteria (Lactobacillus), Phedi O Rhodococcus (Pediococcus), Proteus (Proteus) and Pseudomonas (Pseudomonas) in such a dicarboxylic amino acid decarboxylase.

Representative biogenic amines include putrescine, histamine, tyramine, cadaverine, spermidine, and serotonin. Since biogenic amines act directly or indirectly as neurotransmitters in the body and also affect cardiovascular diseases such as blood pressure control and blood flow, various pharmacological phenomena may occur due to ingestion of biogenic amine-containing foods. Among these, ingestion of histamine and tyramine beyond the degradation limit of the human body causes symptoms such as rash, local skin inflammation, allergy, vomiting, nausea and diarrhea. In addition, blood vessel contraction and heart rate activity are increased by biorenic amines to cause elevation of blood pressure, dilation of pupil and eyelid tissue to promote secretion of tears, excessive salivation of saliva, increase of respiration and increase of blood sugar, And the like.

Glutamic acid is a substance that constitutes the protein of living organisms and has a unique taste and flavor, and is widely used as a seasoning for the production of household and processed foods. Glutamic acid is produced by recovering from a culture solution obtained by culturing a genus of genus Corynebacterium or Brevibacterium genus. In order to increase the productivity of glutamic acid, there is a method in which biotin in a medium is usually confined to a specific range, culture is carried out by adding a surfactant, culture is carried out by adding a penicillin antibiotic, or culture is carried out by adjusting the culture temperature Are known.

Korean Patent No. 0856568 discloses a method for producing chungkukjang using mulberry leaves and silkworms and Korean Patent No. 0324132 discloses a method for producing chungkukjang using soybean koji. . ≪ / RTI >

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned needs, and an object of the present invention is to provide a bacterium having Bacillus subtilis ( Bacillus subtilis) subtilis ) SCKB1319 strain and the above strains to maintain the inherent flavor of Chungkukjang. In order to produce chungkukjang which can enhance the quality and preference of Chungkookjang without adding any other food additives, The present invention is to provide a cheonggukjang which is low in biogenic amine content and high in glutamic acid content as well as improving the preference degree of the cheonggukjang.

In order to solve the above problems, the present invention provides a process for producing soybean milk, comprising the steps of: (a) removing water of soaked soybeans, heating and cooling to 55 to 65 ° C; And (b) inoculating Bacillus subtilis to the cooled soybeans of step (a) and fermenting the fermented soybean oil at 35 to 45 ° C. .

The present invention also provides a cheonggukjang prepared by the above method.

Further, the present invention provides a processed food prepared by processing the above-mentioned Chungkookjang.

In addition, the present invention relates to a method for producing a bacterium having Bacillus subtilis ( Bacillus subtilis) subtilis ) SCKB1319 strain (KCCM 11684P).

The cheonggukjang produced by the method of the present invention can be used to reduce unpleasantness, which is the biggest problem of chonggukjang, and to improve the quality and preference without adding any other food additives or seasonings, and has been developed in accordance with the taste and preference of modern people It will be an opportunity to inherit the traditional food and develop it one step further.

In addition, Bacillus subtilis ( Bacillus subtilis), which has high degrading activity of biogenic amines and has glutamic acid- subtilis ) SCKB1319 strain, it is possible to produce safe and high-quality production of Chongkukjang.

FIG. 1 is a photograph of Chungkookjang fermented for 72 hours at different strain inoculation temperatures.
A: inoculated at 40 ° C, B: inoculated at 50 ° C, C: inoculated at 60 ° C
FIG. 2 is a graph showing changes in moisture content according to the fermentation period of Chungkookjang with different inoculation temperatures.
FIG. 3 is a graph showing changes in pH with fermentation period of Chungkookjang at different inoculation temperatures.
FIG. 4 is a graph showing the change in titratable acidity according to the fermentation period of Chungkukjang with different inoculation temperatures.
FIG. 5 is a graph showing the change in amino nitrogen content during fermentation period of Chungkukjang with different inoculation temperatures.
6 is a photograph of Chungkookjang fermented for 72 hours at different fermentation temperatures.
A: Fermentation at 30 ° C, B: Fermentation at 40 ° C, C: Fermentation at 50 ° C
FIG. 7 is a graph showing changes in moisture content according to the fermentation period of Chungkukjang with different fermentation temperatures.
FIG. 8 is a graph showing changes in pH with fermentation period of Chungkookjang fermentation temperature.
9 is a graph showing the change in titratable acidity according to the fermentation period of Chungkukjang with different fermentation temperatures.
10 is a graph showing the change of protease activity according to the fermentation period of Chungkukjang with different fermentation temperatures.
FIG. 11 is a graph showing changes in amino nitrogen content with fermentation period of chungkukjang with different fermentation temperatures.

In order to achieve the object of the present invention,

(a) subtracting the water of the soaked soybeans, and increasing the temperature to 55 to 65 캜; And

(b) inoculating Bacillus subtilis to the cooled soybeans in step (a), and fermenting the fermented soybeans at 35 to 45 ° C.

In step (a) of the present invention, the water of soybeans soaked for 5 to 7 hours is removed for 25 to 35 minutes, and then the mixture is heated at 110 to 130 ° C for 15 to 25 minutes, To 65 ° C. More preferably, the water of soybeans soaked for 6 hours is removed for 30 minutes, and then the mixture is heated at 121 ° C for 20 minutes and cooled to 58 to 62 ° C. Although the soybean soaked in water as described above can be called soybeans in a state suitable for growth, there is a problem in that the soybean is not sufficiently blown when the soybean is soaked in less than the time, There is a problem that the water-soluble nutrients of soybean are lost through water. In addition, soybean soaked by soaking was prevented from contamination of fungi and other bacteria through the process of elevating at high temperature as described above, and it was prepared as soybeans suitable for the production of chungkukjang without the bean smell. In addition, fermenting the microorganisms by inoculating them at the above-mentioned cooling temperature has high amino nitrogen content and excellent flavor, which not only improves the preference degree but also enables fermentation into chungkukjang having a viscosity suitable for chungkukjang.

Also, in the method for producing a cheonggukjang of the present invention, the Bacillus subtilis strain used for the fermentation in the step (b) may be a strain having a high biogenic amine-decomposing activity and a high production of glutamic acid, but is not limited thereto. Biogenic amines are substances that affect central nervous system neurotransmitters or direct and indirect vasculature control in the body and also affect cardiovascular diseases. It is a nitrogen compound mainly produced by chemical action such as decarboxylation of amino acid and transamination of amino acid . In particular, soybean fermented with soybean as main raw material can easily be exposed to the risk of biogenic amines. At present, however, it does not limit the content of biogenic amines in the genus, but it is necessary to limit it to the minimum. Therefore, the strain used in the present invention is a strain that does not produce biorenic amines but decomposes more than 95% of biorenic amines. In addition, there is no definite range for the production rate of glutamic acid in the strain. However, as the glutamic acid is produced as a decomposition product produced by the bacteria reacting with the protein during the fermentation process, the flavor of Chungkookjang is increased.

The inoculation of step (b) may be performed by inoculating 0.05-0.15% of Bacillus subtilis with respect to the weight of soybeans before the increase, more preferably, the amount of Bacillus subtilis Bacillus subtilis ) can be inoculated 0.1%. The Bacillus subtilis subtilis ) was able to produce chungkukjang with high quality because of low biogenic amine production rate and high glutamic acid production. In addition, by infecting the Bacillus subtilis in an appropriate amount and fermenting it, the protein of the soybean could be decomposed into amino acids to further enhance the original taste and flavor of Chungkukjang. However, in case of inoculation exceeding the above range, And there is a problem that fermentation is not performed well when inoculated under the above range.

Further, in the method of manufacturing a cheonggukjang of the present invention, the fermentation in the step (b) may preferably be performed at a temperature of 35 to 45 ° C for 68 to 76 hours, more preferably at 38 to 42 ° C for 72 hours can do. By fermenting under the above-mentioned conditions and producing chungkukjang, it is possible to maximize the activity of the physiologically active substance, nutritional component and live bacteria of Chungkukjang, while suppressing the generation of materials causing generation of unpleasant odors generated in the fermentation process, , And it was able to inhibit browning phenomenon during storage and distribution process. However, when the fermentation is carried out at less than the temperature and time, there is a problem in that the cheonggukjang tastes less salty, and when the fermentation exceeds the temperature and time, the harmful bacteria multiply and the preference is lowered.

The method for producing a cheonggukjang of the present invention is more specifically

(a) removing water from soybean soaked for 5 to 7 hours for 25 to 35 minutes, then heating at 110 to 130 ° C for 15 to 25 minutes and cooling to 58 to 62 ° C; And

(b) inoculating Bacillus subtilis to the cooled soybeans in step (a), and then fermenting the mixture at 38 to 42 ° C for 68 to 76 hours,

More specifically,

(a) subtracting the water of soybean soaked for 6 hours for 30 minutes, adding to 121 DEG C for 20 minutes and cooling to 60 DEG C; And

(b) inoculating Bacillus subtilis to the cooled soybeans of step (a), and then fermenting the mixture at 40 ° C for 72 hours.

The present invention also provides a cheonggukjang prepared by the above method.

The present invention also provides a processed food obtained by processing the above-mentioned chungkukjang. Examples of the processed food include, but are not limited to, Chungkukjang ring, Chungkukjang stew, and Chungkukjang powder.

The invention further biogenic amines (biogenic amine) Bacillus subtilis (Bacillus having a degrading activity and glutamic acid-producing ability subtilis ) SCKB1319 strain (KCCM 11684P).

The Bacillus subtilis subtilis ) SCKB1319 strain (KCCM 11684P) was isolated from a traditional soybean, and has a biogenic amine-degrading activity and glutamic acid producing ability. The Bacillus subtilis subtilis SCKB1319 strain was deposited at Korean Culture Center of Microorganisms (KCCM) on Apr. 09, 2015 (Accession No .: KCCM 11684P).

In the strain according to an embodiment of the present invention, the biogenic amine may be at least one selected from the group consisting of tyramine, putrescine and cadaverine, but is not limited thereto.

The biogenic amine of the present invention is formed from an amino acid by the action of an amino acid decarboxylase of a microorganism. When a biogenic amine is ingested from a food in excess of the decomposition limit of a human body, the biogenic amine may cause rash, local skin inflammation, Vomiting, nausea and diarrhea.

Hereinafter, embodiments of the present invention will be described in detail. However, the following examples are illustrative of the present invention, and the present invention is not limited to the following examples.

1. Materials and manufacturing methods

1) Materials

Soybeans used domestic soybeans (Jeonbuk Sunchang Army). The strains were purchased from the Sungchang-gun fermented microorganism control center. Bacillus subtilis ( Bacillus subtilis), which is high in biogenic amine degradation rate and high in glutamic acid production, subtilis SCKB1319) Strain (Accession No. KCCM 11684P) was used.

2) Chungkukjang manufacturing

The selected soybeans were washed five times, immersed in water for 6 hours, dehydrated for 30 minutes, and then heated at 121 ° C for 20 minutes. Soybean production to find out the quality characteristics and organoleptic properties of the specific temperature inoculated soybean is steamed soybean is cooled to a 40 ℃ without any molding process, 50 ℃, 60 ℃, and then Bacillus subtilis (B. subtilis SCKB1319) The strain (OD value: 1.0) was inoculated 0.1% of the soybeans before fermentation and fermented at 40 ° C for 72 hours.

In addition, the soybean production to find out the quality characteristics and organoleptic properties of the specific fermentation temperature soybean is cooled to increase the soybean to 60 ℃ and then Bacillus subtilis (B. subtilis SCKB1319) (OD value 1.0) was inoculated at 0.1% of the soybeans before fermentation and fermented at 30 ° C, 40 ° C and 50 ° C for 72 hours, respectively.

2. Experimental Method

1) Strain experiment

(A) Biogenic amine-decomposing activity

HPLC was performed to observe the ability of the selected strain to degrade the biogenic amine. Steam sterilized boiled rice flour was prepared by adding 0.8 mL of NB (nutrient broth) medium containing 16 mg of tyramine, putrescine and cadaverine to 0.3 g of soy flour, and 0.2 mL of the selected strain. Respectively. For comparison, a control group without addition of bacteria was used. In 37 ℃ 48 hours of incubation mix the culture supernatant 0.1 mL, 80 ㎕ acetone soluble 1% daensil chloride, 50 ㎕ saturated Na ₂ CO ₃ obtained by separating 10 minutes centrifugation at 13,000 rpm was screen 1 hours derivative in 45 ℃. To the derivatized sample solution, 0.5 mL of ether was added. After 3 minutes, the separated supernatant was collected, cultured at 50 ° C, evaporated, and dissolved in 0.1 mL of acetonitrile. In the HPLC analysis, 0.1% formic acid (A) dissolved in H ₂ O and 0.1% formic acid (B) dissolved in acetonitrile were used as the reversed phase column and C18 (Capcellpak, 4.6 mm × 150 mm, ~ 10 minutes, A: B = 45: 55; 11-15 minutes, A: B = 35: 65; 16 to 25 minutes, A: B = 20: 80; 26 to 30 min, A: B = 10: 90, 30 min flow rate was 1 mL / min and 10 μl samples were injected.

(B) Glutamic acid production ability

The selected strains were cultured in 2% soy flour medium at 47 ° C for 48 hours and then centrifuged at 13,000 rpm for 10 minutes to remove the cells. 50 μl of the supernatant was dispensed into a 96-well plate, and then 90 μl of an assay buffer of Glutamic Acid Assay Kit (Catalog # K629-100; 100 reactions; Store kit at -20 ° C), 8 μl of glutamic acid developer and 2 μl of glutamic acid enzyme mix, Lt; / RTI > wells. After incubation at 37 ° C for 30 min, the absorbance was measured with a 450 nm microplate reader.

2) Chungkukjang experiment

(A) Moisture measurement

Samples were collected, blashed with a mixer, and water was measured by an infrared moisture meter.

(B) Measurement of pH and titratable acidity

The sample was taken out, ground with a blender, and weighed 5 g. Distilled water was added to make 50 mL. The mixture was thoroughly mixed and measured using a pH meter (Mettler Toledo Gmbh, Switzerland). The titratable acidity was determined by adding 0.1 N NaOH and titrated until the pH reached 8.4.

Titratable acidity (%) = (0.1 N-NaOH titration amount 占 0.009 (lactic acid) 占 F 占 dilution multiple 占 100) / sample amount (g)

(C) Measurement of protease activity

Take 10 g of the sample, add 100 ml of distilled water, mix with shaking at 150 rpm for 1 hour at 30 ° C, and use the filtrate as the crude enzyme solution. Use 0.5 ml of the enzyme solution, 1 ml of Mcllvaine buffer, 2% (milk casein) was added, and the mixture was incubated at 38 ° C for 1 hour in a constant-temperature water bath. Then, 3 mL of 0.4M TCA was added thereto, followed by stirring at 38 ° C for 20 minutes. 1 mL of the resulting filtrate, 5 mL of 0.4 M Na ₂ CO _3, and 1 mL of a 2-fold dilution of phenol reagent were reacted at 38 ° C for 30 minutes, and the absorbance was measured at 660 nm.

(D) Amino-type nitrogen measurement

Amino nitrogen was measured by the Formol method. 1 g of the sample was taken in a beaker, 50 mL of distilled water was added, and the mixture was thoroughly mixed by shaking for 240 seconds. The solution was then titrated with 0.1 N NaOH solution and titrated to pH 8.4. 20 mL of neutral formalin was added thereto, and the mixture was shaken for 20 seconds, and then neutralized with 0.1 N NaOH solution to pH 8.4.

Amino nitrogen (mg%) = (0.1 N-NaOH titration amount 占 1.401 占 F 占 dilution multiple 占 100) / sample amount (g)

(E) Sensory evaluation

The sensory evaluation was carried out in the absence of chungkukjang and evaluated by a panel of nine using the 9 - point scale. The evaluation items were evaluated for four characteristics such as appearance, taste, aroma, and viscous viscosity.

Example  One: Biogenic  Amine analysis result

The results of analysis of the biogenic amine degradation rate of the isolated strains are shown in Table 1. In this experiment, three types of biogenic amines were tested: tyramine, putrescine, and cadaverine. As a result, the Bacillus subtilis SCKB1319 strain has a total of three types of biogenic amine cleavage ability, and each cleavage ability is more than 90% for tyramine, putrescine and cadaverine, so that the biogenic amine can be efficiently removed .

Biogenic Amine Degradation Rate (%) Strain Tyramine Putrescine Cadaverine Bacillus subtilis SCKB1319 95% 91% 95%

Example  2: Glutamic acid Generation

The glutamic acid-producing ability of the isolate strain Bacillus subtilis SCKB1319 is shown in Table 2 below. The content of glutamic acid per 1 mL of 2% soybean medium was converted to 5.954 nmol.

Glutamic acid production ability Strain Glutamic acid (nmol / 2% soybean broth 1 mL) Bacillus subtilis SCKB1319 5.954

Example  3: Quality Characteristics of Cheonggukjang by Inoculation Temperature

For the production of chungkukjang, Bacillus subtilis subtilis SCKB1319) strains were examined to determine whether there was any difference in quality characteristics. Basically, the optimum temperature for sprouting of CJC spores is around 40 ℃ and it is delayed at 50 ℃. However, it does not germinate within 24 hours at more than 55 ℃ or below 10 ℃. In actual work, however, CJK is inoculated immediately after spreading the flesh from the pot The reason for this is that the spore is highly heat-resistant, and if it is given a high-temperature impact for a short period of time, the sprouting effect is promoted. Thus, Bacillus subtilis (B. subtilis SCKB1319) The inoculation temperature of the strain was changed to 40 캜, 50 캜 and 60 캜 to compare the quality characteristics (Fig. 1).

The measurement results of moisture content changes are shown in Fig. At the early stage of fermentation, the temperature was kept similar, but after 48 hours of fermentation, the temperature of the fermentation decreased. It was thought that the drying was caused by evaporation of water during fermentation, and the decrease of moisture was rapidly progressed at the inoculation temperatures of 40 ° C and 50 ° C as a whole.

As a result of observing the pH change according to the inoculation temperature, it was found that a neutral region appeared at 24 hours of fermentation, and was converted into an alkaline region as the fermentation time elapsed (FIG. 3). The conversion of the pH of the chungkukjang into alkaline was considered to be the result of protein degradation. The pH was in the range of 6.5 ~ 7.7 when inoculated at 50 ℃ and 6.4 ~ 7.7 when inoculated at 60 ℃. In the case of inoculation at 40 ° C, the pH was slightly lowered to 6.3 ~ 7.5.

As shown in Fig. 4, the titratable acidity rapidly increased at 24 hours after fermentation and then decreased at 48 hours. Thereafter, no significant change occurred. In the case of inoculation at 40 ℃, the highest acidity was obtained at 0.6 ~ 1.2%, 0.6 ~ 1.1% at 60 ℃ and 0.6 ~ 0.8% at 50 ℃.

Amino nitrogen, which is a measure of the richness of soybean fermented food, is a substance produced by degradation of soybean protein, and is important as a quality index of fermentation of soy sauce. According to the Food Code of Korea, the amino nitrogen content of chungkukjang is defined as 280 mg% or more. Amino nitrogen content in all experimental conditions increased in proportion to the fermentation time (Fig. 5). In the case of inoculation at 60 ℃, 473.7 mg% was shown at 48 hours after fermentation and 582.4 mg% at 72 hours.

Example  4: Sensory evaluation of Cheonggukjang by inoculation temperature

Bacillus subtilis (B. subtilis The results of the sensory evaluation of Chungkookjang prepared by the inoculation temperature of SCKB1319 strain are shown in Table 3. Taste, flavor, and viscosity of the viscous substance at the inoculation temperature of 60 ℃.

Sensory evaluation of Cheonggukjang by inoculation temperature Inoculation temperature (℃) Sensual characteristic Exterior flavor incense Viscosity of viscous substance 40 5.2 4.3 5.1 5.1 50 4.5 5.3 4.9 2.3 60 6.3 6.9 5.2 6.8

Examples 3 and 4, when seen from the results in consideration of quality and the most relevant amino nitrogen of Soybean, sensory evaluation, such as Bacillus subtilis (B. subtilis SCKB1319) The optimal inoculation temperature was determined to be 60 ° C at the time of inoculation.

Example  5: Quality Characteristics of Cheonggukjang by Fermentation Temperature

In order to establish the optimum fermentation temperature for the production of chungkukjang using B. subtilis SCKB1319, B. subtilis SCKB1319) strain was inoculated at a suitable inoculation temperature of 60 ° C and then fermented for 72 hours at each temperature (30 ° C, 40 ° C, and 50 ° C), and then the quality characteristics of Chungkukjang were measured (FIG.

The results of moisture content of Chungkukjang by fermentation temperature are shown in Fig. The fermentation at 30 ℃ showed a gradual decrease in water content but the fermentation at 40 ℃ and 50 ℃ rapidly decreased to about 33% at 72 hours of fermentation. This is due to the drying of the surface of Chongkukjang. It is considered that the surface of Chongkukjang is rapidly dried due to temperature rise when fermenting at 40 ℃ and 50 ℃ compared to 30 ℃.

The pH of Chungkookjang prepared according to fermentation temperature tended to increase with Bacillus subtilis SCKB1319 (Fig. 8). The fermentation at 40 ℃ and 50 ℃ showed higher pH at 6.5 ℃ and pH 6.5 ~ 7.6 at 50 ℃, respectively.

As a result of measuring the change of titratable acidity during the fermentation of Chongkukjang, the Chongkukjang fermented at 50 ° C showed 0.5 to 0.6% as shown in FIG. 9, and showed a constant acidity as the fermentation time elapsed. When fermented at 40 ° C, The fermentation time of fermentation increased rapidly to 24 hours. The content of fermentation increased to 1.3% at 72 hours after fermentation.

Protease is one of the important factors determining the taste of Chungkukjang because it decomposes soy protein and produces amino acid and polypeptide which are rich in flavor. The change in protease activity of Chungkukjang according to the fermentation temperature is shown in Fig. When incubated at 40 ℃, the highest activity was 158.8 unit / g at 72 hours, 136.9 unit / g at 30 ℃, and 95 unit / g when cultured at 50 ℃. g. < / RTI >

The amino acid nitrogen, which is a measure of the taste of soybean fermented food, is caused by the amino acid produced by the protease activity produced by microorganisms during the fermentation of fermented soy sauce. The content of amino nitrogen was 435 mg% at the fermentation temperature of 40 ℃, and the content was slightly lower at 40 ℃ than the fermentation temperature of 30 ℃. % (FIG. 11). These results suggest that the protease activity secreted by the microorganism is low due to the insufficient growth of the microorganism and the decomposition of the soybean protein is not easily occurred.

Example  6: Quality Characteristics of Cheonggukjang by Fermentation Temperature

Bacillus subtilis (B. subtilis The results of the sensory evaluation of Chungkukjang prepared by using the SCKB1319 strain at different fermentation temperatures are shown in Table 4. Viscosity of viscous and viscous materials showed higher score with lower fermentation temperature, and taste and flavor showed the highest score at 40 ℃.

Sensory Evaluation of Cheonggukjang by Fermentation Temperature Fermentation temperature (℃) Sensual characteristic Exterior flavor incense Viscosity of viscous substance 30 5.9 3.9 2.7 6.9 40 5.1 6.5 3.9 5.8 50 2.8 6.1 3.2 2.6

According to the quality characteristics and sensory test results of the cheonggukjang in Examples 5 and 6, the content of B. subtilis SCKB1319) strain at 60 ° C, it is considered appropriate to ferment at 40 ° C.

Korea Microorganism Conservation Center (overseas) KCCM11684P 20150409

Claims (7)

(a) subtracting the water of the soaked soybeans, and increasing the temperature to 55 to 65 캜; And
(b) inoculating Bacillus subtilis to the cooled soybeans of step (a), and fermenting the fermented soybeans at 35 to 45 ° C. The method according to claim 1,
(a) removing water from soybean soaked for 5 to 7 hours for 25 to 35 minutes, then heating at 110 to 130 ° C for 15 to 25 minutes and cooling to 58 to 62 ° C; And
(b) inoculating Bacillus subtilis to the cooled soybeans in step (a), and fermenting the fermented soybeans at 38 to 42 ° C for 68 to 76 hours. Way. [Claim 3] The method according to claim 2, wherein the Bacillus subtilis is a strain having a biogenic amine-degrading activity and glutamic acid producing ability (Deposit No. KCCM 11684P). A cheonggukjang prepared by the method of any one of claims 1 to 3. Processed food processed in accordance with paragraph 4. Biogenic amines (biogenic amine) having a degrading activity of Bacillus subtilis and glutamic acid-producing ability (Bacillus subtilis strain SCKB1319 (KCCM 11684P). The method according to claim 6, wherein the biogenic amine is at least one selected from the group consisting of tyramine, putrescine, and cadaverine. Bacillus subtilis ( Bacillus subtilis) subtilis ) SCKB1319 strain.

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