JPH06253880A - Composite utilization of rice grain - Google Patents

Abstract

PURPOSE:To produce a cyclodextrin from inexpensive rice bran and broken rice by the action of CGTase and to obtain protein-concentrated rice flour and glucose having high utility value as by-products. CONSTITUTION:White bran or broken rice is used as raw material and treated with an enzyme to successively produce cyclodextrin, glucose for fermentation raw material and high-protein rice grain fraction.

Description

Detailed Description of the Invention

[0001]

The present invention utilizes white rice bran or broken rice as a starting material to produce various products with high added value,
Generally, it relates to a technology that is advantageously provided.

[0002]

2. Description of the Related Art Rice is not only one of the most produced crops in the world as a staple food, but also the amino acid of protein contained in rice as compared with other cereals. It has a well-balanced composition and therefore has good nutritional utilization efficiency and is nutritionally equivalent to beef (Food Technology, 35 (1)
1), 38-42, 1981). However, the outer skin portion (alley powder layer) containing most of rice protein is removed as rice bran in the rice polishing process and is hardly used for food. Further, white rice bran and broken rice are produced in the rice polishing process, but most of them are currently mainly used as livestock feed. However, not only crushed rice but also white rice bran and Kamishiro bran produced during the rice polishing process of sake rice still contain 5.0% or more of high quality protein. Therefore, the proteins can be concentrated and separated by specifically converting these starch parts with an enzyme.

Many research and development examples have already been known regarding the production method of cyclodextrin (Starch Science, 2
2,6-10,1975: Journal of Agricultural Chemistry, 51,691
-698, 1977: Starch Science, 36, 35-42, 1
989), the starch substance is converted into a cyclic dextrin by the action of an enzyme, cyclodextrin-glucanotransferase (hereinafter, abbreviated as CGTase) produced by Bacillus genus cells. Cyclic dextrin (cyclodextrin; hereinafter abbreviated as CD) has the property of including various substance molecules in its structure, and by utilizing this property, it stabilizes various volatile spice components and masks malodorous substances, It is also applied in the pharmaceutical industry and food processing fields such as taste improvement (food industry, 31 (4),
30-40, 1988: New Food Indus.
try, 34 (5), 40-44, 1992). However, currently, CDs and their derivatives are not cheap enough to use in large quantities and easily. As starch used as a raw material for CD production, processed starch from horse mackerel, sweet potato, corn, and tapioca is generally used, but there is no direct use of rice bran or broken rice. Therefore, if rice bran or broken rice, which is relatively inexpensive, can be used as a raw material, it naturally helps reduce costs.

By the way, not all of it is converted into CD by the enzymatic treatment of starch, but a considerable amount of dextrin and maltooligosaccharide remains. It can be used as a raw material for the production of lactic acid, citric acid and alcohol. Lactic acid is produced by fermentation of starch, glucose and the like, and is used not only as a sour agent, a flavor buffer or a pH adjuster, but also in a considerable amount as a calcium strengthening adjuster. In the conventional lactic acid fermentation method, starch is saccharified and subjected to fermentation as glucose (glucose), but this requires a considerable cost. Since glucose is a raw material for alcohol, citric acid, etc., as well as for producing lactic acid, as described above, it is clear that if high-purity glucose is supplied at low cost, it will contribute to the reduction of production costs in the fermentation and brewing industry. Is.

[0005]

Means for Solving the Problems As a result of repeated studies to clarify the above-mentioned problems, the present inventors have found that an enzyme produced by a thermophilic bacterium of the genus Bacillus efficiently produces CD using rice bran or broken rice as a raw material. The present invention has been found out. It was also confirmed that high-purity glucose can be easily produced from the mother liquor from which the produced CD has been separated, and that lactic acid can be efficiently produced by using this glucose as a raw material for lactic acid fermentation. Furthermore, as a result of analysis of insoluble matter before CD separation, it was found that the protein content was concentrated to 30% or more in the dry matter, and it was found that this can be applied as a raw material for the production of nutrition foods. The present invention has thus been completed. Hereinafter, the present invention will be described in detail.

In the process of the present invention, rice bran or broken rice is used as a raw material, but rice grains may be used. It is preferable that ground rice and rice grains are ground into the finest possible powder before use in order to accelerate the biosynthetic reaction.

On the other hand, CGTas, an enzyme that biosynthesizes CD
e is mainly produced by Bacillus bacteria,
Among them, B. macerans , B. megateriu
m and B. circulans and the like are well known (Starch Science, 38 (2), 211-215, 1991). In the present invention, as a result of testing various newly found bacterial cells (provided by the Academy of Sciences of the Republic of Armenia) in addition to these bacterial cells, a few bacterial strains were found to be efficient due to characteristics such as growth rate and CGTase activity. We have found that it is suitable for CD production. Table 1 shows these characteristics.

[0008]

[Table 1]

5 to 20% of rice bran or broken rice as a raw material
Although it can be used in the range of (percentage by weight), the concentration is preferably around 10% from the viewpoint of operability and reaction efficiency. Table 2 shows the ratios of the products obtained when different concentrations of rice bran were used.

[0010]

[Table 2]

The rice bran solution was gelatinized by heating at 80 to 100 ° C. for 15 to 30 minutes, and 5 THU of CGTase was added per 1 g of starch.
And liquefy. At this time, 5 to 15 mM / l C
Addition of aCl ₂ was observed to have a promoting effect on liquefaction and subsequent reaction. CGTase was further added to the liquefied mother liquor in an amount of 8 THU per 1 g of starch, and the mixture was cultured at 40 to 50 ° C. for 18 to 24 hours with stirring. After culturing, centrifugation was performed to obtain a precipitate portion in an amount of 4 to 12% in terms of dry weight.
This precipitate is concentrated in protein content of 30% or more,
It can be used as an excellent nutritional food material.

The supernatant was heated with activated charcoal, and the filtrate was concentrated under reduced pressure and allowed to stand at low temperature (4 ° C.) to precipitate β-CD. The yield of β-CD is 10 to 2 of the raw material in terms of dry weight.
The amount was 0%. After removing β-CD, 5% amount of cyclohexane was added to the filtrate and stirred, and the precipitated α-CD was collected by centrifugation, dissolved in water again, and dried with a spray dryer to obtain 8 to 13% amount. Α-CD
was gotten.

Amylase is added to the residual liquid after the CD is harvested to decompose starch and polysaccharides, treated with activated carbon and filtered to obtain a highly pure glucose solution. This glucose solution can be used as it is as a raw material for lactic acid fermentation or the like, or can be prepared into glucose crystal powder by spray drying.

[0014]

[Examples] The present invention is described in more detail below by referring to Examples using T42 strain, but the present invention is not limited thereto.

Shiranuka (sugar percentage 80% or less) was used as a raw material. To 100 g of white rice bran to which 10 mM of CaCl ₂ was added, add water to make 1 liter,
It was gelatinized with stirring for 30 minutes. INMIA-T42 strain (Microbiology Institute of Armenian Academy of Sc) of thermophilic Bacillus bacterium in gelatinized raw material liquid
CGTase produced by Ience Co., Ltd.) is added to 5 THU per 1 g of starch, mixed well at 80 to 85 ° C. for 30 minutes, and then cooled to 50 ° C. CGTase 8T more
Add HU / g and react at 50 ° C. for 24 hours with shaking. After the reaction, the suspension was centrifuged at 8,000 rpm for 15 minutes to obtain about 10 g of a precipitate, which was dried to obtain 5 g of rice flour containing about 40% (weight ratio) of protein. . This protein-rich rice flour is well-balanced and easy to digest, and can be widely used as a nutritional food material such as baby food, pudding and porridge. Table 3 shows the component composition of the obtained rice flour.

[0016]

[Table 3]

The pH of the centrifugal supernatant was adjusted to 5.2 and then 8
Add 0 mg of glucoamylase (124 U / g) and stir at 50 ° C. for 30 minutes to 1 hour. Then 100 ° C
The mixture is heated to 1, the enzyme activity is stopped, activated charcoal is added, and the mixture is filtered and concentrated under reduced pressure until the amount becomes about 1/5. Concentrated liquid is 4 ℃
Β-CD began to crystallize rapidly by placing it at a low temperature. When these crystals were collected and dried, about 14 g of β
-CD powder was obtained. To the remaining solution, 5% (volume ratio) of cyclohexane was added, well stirred, allowed to stand at 4 ° C. for 1 hour, and then centrifuged at 8,000 rpm for 15 minutes. 200 ml of water is added to the precipitate and heated to evaporate cyclohexane. Then, after filtering and drying, about 13 g of α
-CD was obtained.

The supernatant obtained by centrifugation is an almost pure glucose solution, and when dried with a spray dryer, it is about 50 to 50.
60 g of glucose crystal powder was obtained.

[0019]

Industrial Applicability According to the present invention, high-value-added CD, glucose and protein concentrated rice flour can be produced from rice bran and broken rice. Moreover, since the raw materials can be completely used, there is an advantage that no waste residue is generated.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kim Takehisa 9-5 Akahori-shinmachi, Yokkaichi-shi, Mie Taiyo Kagaku Co., Ltd. (72) Inventor Takehiko Yamamoto 9-5 Akahori-shinmachi, Yokkaichi-shi, Mie Solarization Gaku Co., Ltd.

Claims (1)

[Claims] 1. A combined use method of white rice bran and broken rice, which comprises enzymatically treating white rice bran or broken rice as a raw material to produce cyclodextrin, glucose as a fermentation raw material and a high protein rice grain fraction in a stepwise manner.