JP2810993B2 - Defatted food material enriched in γ-aminobutyric acid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defatted food material, for example, used as a raw material for beverages, noodles, confectioneries, soups and the like.

[0002]

2. Description of the Related Art γ-Aminobutyric acid is a kind of amino acid produced by decarboxylation of glutamic acid in a living body and plays an important role in the central nervous system as a neurotransmitter and also has an action of lowering the blood pressure of animals. It is known. Conventionally, γ-aminobutyric acid has been produced by a fermentation method, but there are some problems in terms of production cost, and therefore, development of a food material capable of ingesting a higher concentration of γ-aminobutyric acid is desired. ing.

[0003]

SUMMARY OF THE INVENTION The present inventors have found that glutamic acid, which is a precursor of γ-aminobutyric acid, is contained in a high concentration in the rice germ and the surface layer of the rice grain.
It was found that it was rapidly converted to γ-aminobutyric acid when immersed in water, and it was also found that wheat germ and wheat germ containing germ started to be converted to γ-aminobutyric acid by immersion in water. . Based on such findings, the present inventors have already found rice germ, rice bran including germ, germ rice,
Wheat germ or one of wheat germ containing germ is immersed in water under certain conditions to activate endogenous glutamate decarboxylase, thereby promoting the production of γ-aminobutyric acid, An embryo food material has been proposed in which the content of γ-aminobutyric acid in the product has been dramatically improved (Japanese Patent Application No. 6-27581).
However, such a germ food material enriched in γ-aminobutyric acid has a relatively high content of free fatty acid in the material, and may be about 2 to 10% by weight. As a specific component, it contains a large amount of unsaturated fatty acids such as linoleic acid and linolenic acid, so that it is easily oxidized and rotted, and the flavor of the material is impaired. The range of application to food is narrowing. The reason why a large amount of free fatty acids is contained in the germ food material is considered to be due to the lipid content in the raw material germ, which is contained in the germ during the production process of γ-aminobutyric acid, particularly when the raw material germ is immersed in water. It is considered that the lipase activity hydrolyzes fats and generates free fatty acids. Accordingly, an object of the present invention is to enrich γ-aminobutyric acid in rice germ, rice bran containing germ, germ rice, wheat germ, or wheat germ containing germ under predetermined conditions, Reduce the content to improve the flavor of germ food, taste,
It is an object of the present invention to provide a defatted food material that can be widely applied to the food field in terms of overall digestion, cooking processing, management, and the like.

[0004]

A defatted food material enriched in γ-aminobutyric acid according to the first aspect of the present invention for achieving the above object comprises rice germ, rice bran containing germ, germ rice A defatted product obtained by extracting and separating at least one kind of lipid from wheat germ and wheat germ including wheat germ with n-hexane, at pH 2.5 to 7.5 and immersed in water at 50 ° C or lower. It is characterized by. Further, the defatted food material enriched in γ-aminobutyric acid according to the invention of claim 2,
A defatted product obtained by extracting and separating at least one lipid from rice germ, rice bran containing germ, germ rice, wheat germ, and wheat germ containing wheat germ with subcritical or supercritical carbon dioxide has a pH of 2.5 to It is obtained by immersing in water at a temperature of 7.5 and 50 ° C. or lower.

[0005] The rice used in the present invention is not limited to varieties,
It is more preferable to use a giant germ rice having a high embryo weight ratio and a variety having a large γ-aminobutyric acid production amount. Germ rice can be easily prepared by polishing rice with a rice mill and removing bran. It is also possible to use germ-containing rice bran or germ rice. After the germ is further ground by a grinding rice mill, the germ is separated from the powder and bran derived from the endosperm through an appropriate sieve (about 32 mesh).

[0006] Wheat does not limit the variety. As the wheat germ and the wheat containing the wheat germ, a germ-containing fur (kobusuma, oobuma) obtained by milling wheat with a mill (for example, a Buhler test mill, manufactured by Bühler Co., Ltd.) can be used. Preferably, Kobusuma is used. Wheat germ can be easily obtained from Kobusuma by sieving with an appropriate sieve (about 32 mesh).

[0007] Regarding the temperature conditions for lipid extraction, it is desirable to perform the extraction at a temperature not higher than the boiling point of n-hexane (69 ° C). Desirably, extraction is performed at 15 ° C to 30 ° C, more preferably at about 20 ° C. This means that when extracted at this temperature, γ-
This is because the enrichment ratio of aminobutyric acid is higher. In addition,
When extraction is performed at a temperature higher than the boiling point of n-hexane (69 ° C.), glutamate decarboxylase endogenous in embryos and the like is inactivated, and the amount of γ-aminobutyric acid produced is reduced. When the extraction is performed at 20 ° C., the extraction may be performed for at least about one hour. The number of extractions is desirably two or more.

For the removal of n-hexane after extraction, γ
-Before the enrichment of aminobutyric acid, defatted germs and the like may be separated from n-hexane by filtration. Although it is possible to evaporate n-hexane by heating, exposing defatted rice germ and the like to a high temperature deactivates endogenous decarboxylase. Note that even a small amount of n-hexane does not affect the enrichment rate of γ-aminobutyric acid.

[0009] One of the features of the present invention is that the raw material germ and the like are defatted before the raw material is enriched with γ-aminobutyric acid in the present invention. This is because if the raw material germ or the like is enriched with γ-aminobutyric acid and then defatted, the enriched γ-aminobutyric acid is flowed into the extraction solvent and the amount thereof is likely to decrease. On the other hand, γ
Performing defatting before enriching aminobutyric acid makes it possible to reduce the amount of lipid in the raw material and increase the amount of γ-aminobutyric acid enriched.

The conditions for enriching defatted germ and the like with γ-aminobutyric acid are pH 2.5 to 7.5 and 50 ° C. or lower in order to increase the activity of glutamate decarboxylase present in the germ and the like. . Specifically, water adjusted to pH 2.5 to 7.5, preferably pH 3.0 to 7.0, more preferably pH 5.5 to 6.0
Add 2 to 10 times the amount and add 5 to 50 ° C or less, usually 10 to 50 ° C.
20 minutes or more at 0 to 150 strokes / minute, usually 20 minutes to 24 hours,
Shaking is preferably carried out at 80 to 120 strokes / min for 40 minutes to 10 hours, more preferably at 40 ° C at 100 strokes / min for 4 to 8 hours. The acid used for adjusting the pH is an organic acid such as citric acid or malic acid, or an inorganic acid such as hydrochloric acid, sulfuric acid or phosphoric acid. Also, as the alkali, sodium hydroxide,
Potassium hydroxide, calcium hydroxide, sodium carbonate,
Sodium phosphate or the like is used. With this process,
Glutamic acid endogenous in embryos and the like can be converted to γ-aminobutyric acid. At this time, proteolytic enzymes also act at the same time, and proteins contained in embryos and the like are degraded,
Glutamic acid is supplied and can be efficiently converted to γ-aminobutyric acid.

Also, rice germ, rice bran containing germ, germ rice,
At least one of wheat germ and wheat germ
Conditions for extracting species lipids with subcritical or supercritical carbon dioxide are described in the critical point of carbon dioxide (31.0
(° C, 72.9atm). Carbon dioxide in a critical state has a density close to that of a liquid and a large diffusion coefficient close to that of a gaseous substance, and can efficiently extract lipids such as embryos from such characteristics.

Further, in the present invention, ethyl alcohol can be used in place of n-hexane as a solvent for extracting lipids such as embryos. It is also possible to use a mixed solvent of n-hexane and ethyl alcohol.

[0013]

Embodiments of the present invention will be described below. (Preparation of raw materials) For germ rice, Sasanishiki rice is converted to a normal rice mill.
(For example, RMA-150, manufactured by Yanagisawa Seisakusho) to remove the bran, and then the germ rice is further ground by a grinding rice mill (for example, TM5, manufactured by Satake Seisakusho), and then appropriately sieved (32
Rice germ was separated from the endosperm-derived flour and bran (mesh position).

(Example 1: Examination of temperature conditions) To 200 g of the prepared rice germ, 1000 ml of n-hexane was added, and -20 ° C, 0 ° C, 10
After stirring for 2 hours at each temperature condition of 20 ° C., 20 ° C., 30 ° C., 40 ° C., 60 ° C. and 69 ° C. (reflux temperature), one operation to extract and separate lipids was performed.
I went there. After extraction, the defatted germ was filtered to remove n-hexane. Next, 8 ml of water adjusted to pH 5.6 was added to 0.5 g of the obtained defatted germ, and the mixture was shaken at 40 ° C. at 100 strokes / min for 4 hours to generate γ-aminobutyric acid.

(Example 2: Examination of extraction time) To 200 g of the prepared rice germ, 1000 ml of n-hexane was added, and 30 ° C and 69 ° C.
(Reflux temperature), the mixture was stirred under the conditions of each extraction time of 1, 2, 4, 6, and 24 hours, and then an operation of extracting and separating lipid was performed once. After extraction, the defatted germ was filtered to remove n-hexane. Next, 8 ml of water adjusted to pH 5.6 was added to 0.5 g of the obtained defatted germ, and the mixture was shaken at 40 ° C. at 100 strokes / min for 4 hours to generate γ-aminobutyric acid.

(Example 3: Examination of the number of extractions) To 200 g of the prepared rice germ, 1000 ml of n-hexane was added, and the mixture was stirred at 30 ° C. for 2 hours. The number of extractions was performed. After extraction, the defatted germ was filtered to remove n-hexane. Next, pH 5.6 was added to 0.5 g of the obtained defatted germ.
8 ml of water adjusted to above was added and shaken at 40 ° C. at 100 strokes / min for 4 hours to generate γ-aminobutyric acid.

(Comparative Example) To 0.5 g of raw rice germ without degreasing
8 ml of water adjusted to pH 5.6 was added, and the mixture was shaken at 40 ° C. at 100 strokes / minute for 4 hours to generate γ-aminobutyric acid.

(Comparison of free fatty acid content) Next, the free fatty acid content of the samples obtained in Examples 1 to 3 and Comparative Example was compared. The measurement was performed according to the following Japanese agricultural and forestry standard measurement method. [Method for measuring Japanese Agricultural Standards for vegetable oils (15 acid value)]
(A sample containing a solid or a solid sample is melted by heating.) In a Erlenmeyer flask, weigh properly according to the sampled amount corresponding to the estimated acid value in the table below, and transfer the solvent to 50-100 m
Add a few drops of l and the indicated indicator to completely dissolve the sample. Acid value Sample Weighing accuracy 0-5 20.0 g ± 0.05 g 5-15 10.0 g ± 0.05 g 15-30 5.0 g ± 0.05 g 30-100 2.5 g ± 0.001 g 100 or more 1.0 g ± 0.001 g N / 10 Titrate with a potassium hydroxide ethyl alcohol standard solution, and calculate the acid value by the following equation, using the time when the discoloration of the indicator continues for 30 seconds as the neutralization point. Generally, phenolphthalein is used as an indicator, and alkaline blue 6B is used for rice oil. Acid value = 5.611 × A × F / B A: Amount of N / 10 potassium hydroxide ethyl alcohol standard solution used F: Factor of N / 10 potassium hydroxide ethyl alcohol standard solution B: Sample (g)

The results are shown in Table 1.

[Table 1] According to Table 1, each of the samples of Examples 1 to 3 contained 0.42 to 0.45 wt% of the free fatty acid in the germ, whereas the sample of the comparative example contained 5.54 wt%. This allows n
It can be seen that the free fatty acids were sufficiently extracted and separated with -hexane.

(Comparison of γ-aminobutyric acid enrichment ratio) Next, the enrichment ratio of γ-aminobutyric acid was compared for each of the samples obtained in Examples 1 to 3 and Comparative Example. The comparison of the enrichment ratio of γ-aminobutyric acid was measured under the conditions shown in Table 2.

[Table 2]

The results showing the enrichment rate of γ-aminobutyric acid are shown in Tables 3 to 6 and FIGS. Table 3 shows the results of Comparative Examples, and Tables 4 to 6 and FIGS. 1 to 3 show the results of Examples 1 to 3, respectively.
In Tables 3 to 6, the "reference amount" indicates the content of γ-aminobutyric acid originally contained in the live germ.

[Table 3]

[Table 4]

[Table 5]

[Table 6] As shown in Tables 3 to 6, each of the samples of Examples 1 to 3 has a higher enrichment amount than the sample of the comparative example, and the enrichment amount of γ-aminobutyric acid is higher than that of the sample of the comparative example. Conversion rate.
This indicates that the rice germ is defatted and promoted without inhibiting the enrichment of γ-aminobutyric acid. In addition, from the results in Table 4, it can be seen that the enrichment of γ-aminobutyric acid is highest when the extraction temperature is about 20 ° C. to 30 ° C.
From the results shown in Table 5, it can be seen that the extraction time when extracting at 30 ° C. is preferably within 4 hours. From the results according to Table 6, the number of extractions when extracting at 30 ° C. for 2 hours is as follows:
It turns out that two or more times are desirable.

(Evaluation of Flavor) Next, the samples obtained in Examples 1 to 3 and Comparative Example were evaluated for aroma and taste. The evaluation was performed 5 days after the preparation of the sample, and the roasted sample was similarly evaluated. Table 7 shows the results. In Table 7, “○” is the best, “△” is good,
“▲” indicates discomfort.

[Table 7] As shown in Table 7, in each of Examples 1 to 3, good results were obtained as compared with Comparative Examples. In particular, roasting the defatted one increased the flavor as compared to the roasted raw germ.

(Degreasing by Critical Extraction Method) In Examples 1 to 3, the raw rice germ was degreased using n-hexane as an extraction solvent. It is also possible to perform degreasing using an extraction solvent. For example, 500 g of rice germ is mixed with carbon dioxide in a supercritical state at 40 ° C. and 220 kg / cm 2 to extract oil or
Further, 500 g of rice germ is mixed with carbon dioxide in a subcritical state of 220 kg / cm 2 at 30 ° C. and extracted to obtain defatted rice germ. The step of enriching defatted rice germ with γ-aminobutyric acid can be performed by the same operation as in Examples 1 to 3 described above. When the raw material germ is defatted by the critical extraction method, the method of removing the solvent (carbon dioxide) used for the extraction from the defatted germ is not by the heat removal method, but the pressure of the extraction device is set to normal pressure at a temperature of 40 ° C or less The used solvent can be removed from the raw material germ only by returning to. As a result, there is an advantage that the heat-sensitive decarboxylase is not deactivated.

[0024]

As described above, according to the defatted food material of the present invention, at least one lipid selected from the group consisting of rice germ, rice bran containing germ, germ rice, wheat germ, and wheat germ containing n -The defatted product obtained by extraction and separation with hexane is enriched in γ-aminobutyric acid under predetermined conditions, and the content of free fatty acids in the raw material is significantly reduced. Obtainable. (a) The flavor is greatly improved, and the range of application as a food material is expanded. (b) Preservation of rice germ etc. is improved by defatting, γ
-A large amount of water immersion can be performed efficiently when enriching aminobutyric acid. (c) Rice germ or the like containing high lipids can be used as a low-lipid food. (d) Since the amount of γ-aminobutyric acid enriched per weight is improved by defatting, a food material containing a higher concentration of γ-aminobutyric acid can be provided.

[Brief description of the drawings]

FIG. 1 is a characteristic diagram showing a relationship between an extraction temperature and an amount of γ-aminobutyric acid.

FIG. 2 is a characteristic diagram showing a relationship between an extraction time and an amount of γ-aminobutyric acid.

FIG. 3 is a characteristic diagram showing the relationship between the number of extractions and the amount of γ-aminobutyric acid.

Continued on the front page (72) Inventor Taro Murakami Oriza Yuka Co., Ltd. (72) Inventor Kiyoji Nakagawa Northern character Numata Ichibanchi Ichinomiya Town, Ichinomiya City, Aichi Prefecture Incorporated (72) Inventor Hiromichi Murai Oriza Yuka Co., Ltd. (56) References JP-A 7-213252 (JP, A) (58) Fields surveyed Int.Cl. ⁶ , DB name) A23L 1/305 A23L 1/172

Claims (2)

(57) [Claims] 1. A defatted product obtained by extracting and separating at least one lipid from rice germ, rice bran containing germ, germ rice, wheat germ, and wheat germ containing n-hexane with pH 2.5.
Γ- obtained by immersion in water under conditions of ~ 7.5 and 50 ° C or less
A defatted food material enriched in aminobutyric acid. 2. A defatted product obtained by extracting and separating at least one lipid from rice germ, rice bran containing germ, germ rice, wheat germ, and wheat germ containing wheat with subcritical or supercritical carbon dioxide. Is a defatted food material enriched in [gamma] -aminobutyric acid obtained by immersion in water under conditions of pH 2.5 to 7.5 and 50 [deg.] C. or lower.