JPH08173077A - Low-smelling fermented soybean and its production - Google Patents

Abstract

PURPOSE: To obtain low-smelling nutritionally excellent fermented soybeans capable of reducing only peculiar ammonia smell without deteriorating flavor or taste as fermented soybeans essential to NATTO (fermented soybeans). CONSTITUTION: The low-smelling fermented soybeans contain at least soybeans and a catechin compound or its derivative as essential ingredients. A plant extract or a tea leaf, a pulverized substance of Gambir, etc., are preferably used as the catechin compound. Any of an unfermented green tea leaf, a fermented tea leaf or a semifermented tea leaf can preferably be used as the tea leaf. The catechin compound may be added to either of raw material soybeans before fermentation or fermented soybeans after the fermentation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to low-odor natto, the purpose of which is to reduce the ammonia odor peculiar to natto without impairing the flavor and taste of the soybean ferment of natto. It is also to provide an excellent low-odor natto and its manufacturing method.

[0002]

BACKGROUND OF THE INVENTION Natto is a fermented food in which steamed soybeans are reacted with natto bacteria to cause mucus fermentation. Vitamin B ₂ synthesized during fermentation and accumulated digestive enzymes are most effective in the digestive tract. It is one of the extremely nutritious foods that is affected by. In particular, fat is mostly linoleic acid, which plays a role in cholesterol lowering in the blood vessels and is expected to prevent arteriosclerosis. Also, rice foods low in lysine are easy to digest soybean protein with a relatively high lysine content. There is a nutritional value in forming and feeding. After the high-growth economy, Japanese dietary habits have changed drastically, and Western diets centered on animal protein and animal fat have become mainstream.
However, in recent years, the prevalence of adult diseases such as hypercholesterolemia and arteriosclerosis in the Japanese people has become extremely high, and traditional Japanese foods centering on soybeans and seaweeds have replaced the Western-style diet. It is starting to be reviewed.

[0003]

2. Description of the Related Art Generally, when natto is eaten, a method is used in which shijyoyu, green onions, shavings and bonito are added as they are, stirred well, and then simmered in warm cooked rice. Alternatively, it is usually adopted to eat it as it is sandwiched in bread. However, natto has a peculiar ammonia odor produced by fermentation, and its color is dark brown, so it is generally recognized as one of the foods that is not easily accepted. Therefore, in view of such circumstances, in JP-A-62-244362, shiso powder obtained by crushing sun-dried shiso into 80 to 180 mesh is added in an amount of 3 to 12% based on boiled soybean which is a raw material for natto. The manufacturing method of natto was disclosed. In addition, JP-A-61-1
No. 81351 discloses that garlic natto with garlic characterized in that minced garlic and grated garlic are mixed with steamed soybeans, natto bacteria are planted in soybeans and then fermented, and dehumidification is performed during the progress of the fermentation. Was disclosed.

[0004]

However, the above-mentioned JP-A-62-244362 and JP-A-2-2731 are known.
In the technology disclosed in Japanese Patent Publication No. 53, since the flavor of perilla or garlic added is added to natto, these additives impair the flavor of natto's original soybean fermented product, and the natto's original taste is sufficiently imparted. There was a problem of not being able to taste. Therefore, in the industry, since natto, which has a very high nutritional value and is suitable as a health food, is widely spread, it is possible to reduce only a unique ammonia odor without impairing the flavor and taste as the natto original soybean fermentation product. The creation of low-odor natto and its manufacturing method has been desired.

[0005]

In the present invention, the above-mentioned conventional problems are solved by providing a low-odor natto characterized by containing at least soybean and a catechin compound as essential components.

[0006]

By containing the raw material soybean and the catechin compound as essential components, the alcohol odor peculiar to natto produced by fermentation can be reduced, and the natto itself can be preserved well. Moreover, even if the alcohol odor is reduced, the flavor and taste as the soybean fermented product of natto is not impaired. When catechin compounds such as tea leaves and / or crushed Assen drug are used, not only alcohol odor peculiar to natto is reduced, but also vitamins and minerals are strengthened, and the nutritional value is extremely high. It is possible to make the optimum low-odor natto.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of the low-odor natto and its manufacturing method according to the present invention will be described in detail below. The low-odor natto of the present invention contains soybean and a catechin compound as essential components. As the raw material soybean, conventionally known soybeans for natto are not particularly limited, and any one can be suitably used.

As the catechin compound, any one or two or more appropriately selected from catechin compounds such as epigallocatechin gallate, epigallocatechin, epicatechin, epicatechin gallate, gallocatechin, and catechin may be used. It can be preferably used. Such a catechin compound may be extracted from a plant and used as a purified product, or an extract of a catechin-containing plant, or even a pulverized product of the catechin-containing plant itself. It may be. Preferable examples of the catechin-containing plant include tea and Assen drug.

As the tea, an extract obtained from a dried product such as tea leaves and tea trees, or a dried and pulverized product thereof is used as it is. As tea leaves, the enzyme (polyphenol oxidase) contained in the tea leaves is inactivated by heating during the tea making process to prevent unfermented tea (green tea) that prevents the oxidation of tea components, or oxidase in the tea leaves. Fermented tea (black tea) produced by promoting the oxidation of tea components, and further, half-fermented tea (oolong tea), which is roasted in a kettle at the time of fermenting tea leaves a little to give off an aroma, can be suitably used. Yes, but more preferably fermented tea (green tea),
It is preferably used because the alcohol odor peculiar to natto can be effectively reduced without impairing the flavor of the soybean fermented product. Specifically, any one or more of steamed tea such as sencha, gyokuro, tencha (matcha), kabusecha, bancha, and jade green tea, or pot-baked tea such as gyokuro tea and Chinese green tea are appropriately used. Although it can be selected and suitably used, more preferably, "deep-steamed tea" in which the steaming heat treatment step is performed longer than usual is preferably used. "Deep-steamed tea" is produced by steam heat treatment that is performed for a relatively long time.
This is because the oxidase is completely destroyed and the chlorophyll and taste components are fixed in the tea leaves, which is desirable for ingestion for the purpose of promoting health.

As an Asen drug, there is Uncaria gambir
The extract obtained from the dried product of leaves and young shoots of Rudiaceae), or the dried pulverized product thereof is used as it is.
When using the extract, alcohol, water, acetone-
Appropriate solvents usually used for plant extraction such as water, ether, ethyl acetate and the like can be used. The concentrate of the extract solution extracted with such a solvent as it is, or further obtained by selectively adsorbing and purifying this extract solution using an adsorption resin or the like is not particularly limited, It can also be used.

Further, in the present invention, in addition to the one isolated as a catechin compound simple substance, for example, an oxide of a catechin compound obtained from fermented tea (black tea), specifically a free form or ester form of thearubidine, theaflavin or the like. A compound can also be used as an active ingredient.

In addition to the above-mentioned extract, when a dry pulverized product of tea leaves or Assen medicinal leaves is used, the pulverized product is preferably adjusted to a size of about 60 to 200 mesh. However, it is not particularly limited. Alternatively, in the present invention, a freeze-dried product of tea leaves or Asenyaku leaves or young shoots can also be used. As the freeze-drying method, for example, a dry pulverized product of the extract is frozen at -10 ° C or lower and pulverized with a pulverizer such as a ball mill in this frozen state, or -10 such as liquid nitrogen or liquid helium.
A method of pulverizing while contacting with an ultra-low temperature refrigerant having a boiling point of 0 ° C. or less can be suitably adopted, but is not particularly limited.

The method for producing the low-odor natto of the present invention containing the above-mentioned catechin compound and soybean as essential components is as follows. However, a method obtained by performing fermentation for a predetermined time can be exemplified. That is, in accordance with a conventional method, the raw material soybean is dipped in water to absorb water to a weight of 2.2 to 2.5 times to soften the tissue, and then the soybean is steamed. Next, about 5 to 25% of a catechin compound (extract or tea leaves or Asenyaku crushed product, frozen crushed product, etc.) is added to the obtained steamed soybean, and this is inoculated with natto bacterium and 40 to 50 ° C. When fermented for 16 to 24 hours, a stringy low odor natto can be obtained. further,
If necessary, koji and salt may be added to the obtained string natto and aged for 2 to 4 weeks.

In addition to the above-mentioned production method, a production method of fermenting raw soybeans according to a conventional method and then adding a catechin compound to obtain low-odor natto is also suitably used in the present invention. Here, the addition amount of the catechin compound used is not particularly limited, but it is preferably added within the range of about 5 to 25% with respect to the raw material soybeans used.

As described above, in the low-odor natto according to the present invention, the presence of the catechin compound causes the alcohol odor produced during fermentation to be adsorbed, and the odor of alcohol is not felt during feeding. Moreover, the antioxidative effect of the catechin compound improves its preservability. When crushed tea leaves are used as the catechin compound, vitamins A, B ₁ , B ₂ contained in the tea leaves,
C, E, niacin, folic acid, vitamins such as biotin,
Calcium, potassium, magnesium, iron, manganese,
Minerals such as sodium, catechins, flavonols,
Since tannins such as leuco anthocyan and phenol carboxylic acid can be ingested, the natto has a high nutritional value with a very enhanced nutritional component. Moreover, even if such a catechin compound is added to reduce the alcohol odor peculiar to natto, it does not impair the flavor and taste as the original fermented soybean fermented soybeans, and to fully enjoy the flavor as soybean fermented product. You can

[0016]

EXAMPLES The effects of the low-odor natto and the method for producing the same according to the present invention will be described in more detail below with reference to examples. However,
The present invention is not limited to the following examples.

(Example 1) 100 g of soybean was immersed in water at room temperature for 20 hours, drained, and then pressure-ripened using a pressure can (10 minutes at a pressure of 2 kg) to obtain 220 g of steamed soybean. To this steamed soybean, 35 g of deep-steamed tea dry powder (100 mesh) was added, and natto was sprinkled and ingested and mixed well, then fermented at 45 ° C. for 22 hours, and then aged at 5 ° C. for 24 hours. The natto of Example 1 was obtained. (Example 2) 100 g of soybean was immersed in water at room temperature for 20 hours, drained, and then pressure-ripened using a pressure can (10 minutes at a pressure of 2 Kg) to obtain 220 g of steamed soybean. This steamed soybean was sprayed with natto bacteria, mixed well, fermented at 45 ° C. for 22 hours, and then aged at 5 ° C. for 24 hours. To the natto obtained, 35 g of deep steamed tea dry powder (100 mesh) was added. And mixed well to obtain natto of Example 2.

(Example 3) Example 1 except that gyokuro dry powder (120 mesh) was used in place of the deep-steamed tea powder.
The same natto of Example 3 was obtained. (Example 4) Natto of Example 4 was obtained in the same manner as in Example 2 except that the gyokuro dried powder (120 mesh) was used in place of the deep-steamed tea powder.

(Example 5) Natto of Example 5 was obtained in the same manner as in Example 1 except that black tea powder (120 mesh) was used in place of the deep-steamed tea powder. (Example 6) Black tea powder (12
Example 6 similar to Example 2 except that (0 mesh) was used.
Got natto.

Example 7 Natto of Example 5 was obtained in the same manner as in Example 1 except that oolong tea dry powder (100 mesh) was used in place of the deep-steamed tea powder. (Example 8) Natto of Example 8 similar to Example 2 was obtained except that oolong tea dry powder (100 mesh) was used in place of the deep-steamed tea powder.

(Example 9) 500 g of dried tea leaves were finely chopped,
Extract overnight with 3 liters of methanol. Natto of Example 9 was obtained in the same manner as this except that the extract was concentrated to dryness and used instead of the deep-steamed tea powder of Example 1. (Example 10) Asa medicinal leaves (500 g) were cut into small pieces and extracted with 3 liters of methanol overnight. Natto natto of Example 10 similar to this was obtained, except that this extract was concentrated to dryness and used instead of the deep-steamed tea powder of Example 1.

Example 11 A mixture of epigallocatechin gallate, epigallocatechin, epicatechin, epicatechin gallate, gallocatechin, and catechin extracted from tea leaves and purified was replaced with the deep-steamed tea powder of Example 1. The same natto of Example 11 was obtained except that it was used. (Example 12) After drying Assen medicinal leaves, they were pulverized to about 30 mesh, frozen at -30 ° C, and pulverized to about 100 mesh with a pulverizer such as a ball mill in this frozen state. Natto of Example 12 was obtained in the same manner as in Example 12 except that it was used in place of the deep-steamed tea powder.

Comparative Example 1 100 g of soybean was immersed in water at room temperature for 20 hours, drained, and then pressure-ripened using a pressure can (10 minutes at a pressure of 2 Kg) to obtain 220 g of steamed soybean. After inoculating the steamed soybeans with Bacillus natto and thoroughly mixing,
After fermenting at 45 ° C. for 22 hours, it was aged at 5 ° C. for 24 hours to obtain natto of Comparative Example 1. (Comparative Example 2) 100 g of soybean was immersed in water at room temperature for 20 hours, drained, and then steamed under pressure using a pressure can (pressure: 2K).
g for 10 minutes) to obtain 220 g of steamed soybean. After adding 35 g of this steamed soybeans to ground soybean flour (100 mesh), sprinkling and ingesting Bacillus natto was thoroughly mixed, fermented at 45 ° C. for 22 hours, and then aged at 5 ° C. for 24 hours. I got natto.

[0024]

[Test Example] With respect to the natto obtained in Examples 1 to 12 and Comparative Examples 1 to 2, a panel consisting of 20 men and women aged 18 to 40 was used, and the odor of alcohol and the original flavor of natto were evaluated. A sensory test was conducted. Regarding the alcohol odor, the natto obtained in Examples 1 to 8 and the natto of Comparative Example 1 were compared and a sensory test was conducted to find out how much difference there was. Compared to Comparative Example 1, those that felt a strong natto smell were marked with ×, those that felt similar were marked with △, those with a weak natto smell were marked with ◯, and those with little natto smell were hardly felt.
The evaluation results were the most frequently answered. Regarding the original flavor of natto, the natto obtained in Examples 1 to 8 and Comparative Example 2 and Comparative Example 1 were used.
When compared with the natto of No., the one in which the original flavor of the natto was not felt at all was ×, the one whose flavor was not much different from that of the comparative example 1 was ◯, and the flavor of the natto was more than that of the comparative example 1. Those with good results were evaluated as ⊚, and the answers with the most answers were taken as the test results. Table 1 shows the results.

[0025]

[Table 1]

[0026]

As described in detail above, the present invention is a low-odor natto characterized by containing at least soybean and a catechin compound or its derivative as essential components. As is apparent, it has an excellent effect that it is possible to reduce only the alcoholic odor peculiar to natto without increasing the flavor and taste as the original soybean fermented product of natto, and to improve its preservability. In addition, when crushed tea leaves are used as the catechin compound, various vitamins and minerals are strengthened,
It has the excellent effect of becoming a nutritionally very valuable health food.

Claims (6)

[Claims] 1. A low-odor natto containing at least soybean and a catechin compound or a derivative thereof as essential components. 2. The low-odor natto according to claim 1, wherein the catechin compound or its derivative is a catechin compound or its derivative contained in a plant extract. 3. The low-odor natto according to claim 1, wherein the catechin compound or a derivative thereof is a catechin compound or a derivative thereof contained in ground tea leaves and / or crushed Assen drug. 4. The low-odor natto according to claim 1, wherein the catechin compound or a derivative thereof is a catechin compound or a derivative thereof contained in a freeze-pulverized product of tea leaves and / or Assenyaku. 5. A low-odor natto, which is obtained by adding a catechin compound or a derivative thereof to raw soybeans and then fermenting the soybeans by a conventional method. 6. A method for producing low-odor natto, which comprises fermenting raw soybeans by a conventional method, and then adding a catechin compound or a derivative thereof to the fermented soybean.