JP2006217813A - Rice processed product and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an indigestible rice processed product, and a rice processed product inhibiting increase in level of blood sugar after eating, more specifically, the rice processed product comprising rice highly containing indigestible starch as a raw material. <P>SOLUTION: The rice processed product comprises mutant rice where the ratio of the amylopectin short chain to the whole amylopectin chain is ≤20%, as a raw material, and is provided for being eaten in a granular state or a powdery state. The mutant rice is such that a glucose polymerization degree of the amylopectin short chain is 6-12, and the ratio of the amylopectin short chain to the whole amylopectin chain is ≤20%. The method for producing the rice processed product to be eaten in granular or powdery state is provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a processed rice product and a method for producing the same, and more particularly to a processed rice product made from rice with a high resistance to starch (resistant starch). More specifically, it is a grained food form such as cooked rice, germinated brown rice, rice bran or high-pressure processed rice made from rice with a high digestible starch, or a powdered food form such as bread, noodles or rice crackers, and has an inhibitory effect on blood sugar rise. It relates to processed rice products.

  Recently, from the viewpoint of preventing lifestyle-related diseases such as diabetes, hyperlipidemia and heart disease, or from the viewpoint of food development for patients with lifestyle-related diseases, foods that are difficult to digest in the body because they are not susceptible to degradation by digestive enzymes There is a need for a processed rice product that suppresses blood sugar elevation after eating.

  Conventionally, it has been reported that rice having a high amylose content of rice starch, that is, high amylose rice or Indian rice is rice that meets the above-mentioned purpose, that is, rice with a high starch content that is difficult to digest.

However, high amylose rice and Indian rice are extremely hard and do not meet the tastes of Japanese people, and the amount of starch that is difficult to digest (resistant starch, hereinafter referred to as RS) is measured. In comparison between rice, it is certain that there are more RSs than low amylose rice, medium amylose rice, or Japanese rice, but even in high amylose rice and Indian rice, the amylose content is 30% to 35%. The difference was not significant, and was an order of magnitude less than that of high amylose corn with high RS (amylose content of 50% to 75%), for example.
Therefore, even when digestion tests with digestive enzymes are performed, RS of high amylose rice and Indian rice is orders of magnitude less than that of high amylose corn, and it can be expected to prevent lifestyle-related diseases and suppress blood sugar elevation after eating. There wasn't.

  The purpose of the present invention is to solve these problems of the prior art, from the viewpoint of preventing lifestyle-related diseases such as diabetes, hyperlipidemia and heart disease, or from the viewpoint of food development for patients with lifestyle-related diseases. The object is to provide foods that are difficult to be digested by the body because they are not easily degraded by enzymes, and processed rice products that suppress the increase in blood sugar after eating. More specifically, the first object of the present invention is to provide a processed rice product made from rice having a high digestible starch.

  The second object of the present invention is to provide a processed product in the form of a grain meal such as cooked rice, germinated brown rice, rice bran, or high pressure treated cooked rice with a high resistant starch.

  The third object of the present invention is to provide a processed product in the form of a powdered food such as bread, noodles or rice crackers, which are rich in resistant starch.

A feature of the present invention is that the amylopectin is a mutant rice having a short short chain, that is, a mutant rice lacking starch branching enzyme II b, wherein the ratio of the amylopectin short chain to the total amylopectin chain is 5 to 20%. It is a processed rice product. This mutant rice with a short short chain of amylopectin was developed by Mitsuru Sato and others of Kyushu University using methylnitrosourea (MNU) treatment (Plant Physiology, vol.127, pp.459-472, 2001). ).
Furthermore, the processed rice product is a processed product in the form of a grain meal such as cooked rice, germinated brown rice, rice bran or high-pressure processed rice, and the processed rice product is a processed product in a powdered form such as bread, noodles or rice crackers. Features. The present invention also provides a method for producing processed rice products.

  The second feature of the present invention is that the degree of glucose polymerization of the amylopectin short chain of mutant rice is 6 to 12, the ratio of the amylopectin short chain to the total amylopectin chain is 20% or less, and the RS content is 5% or more. It is to be.

  The third feature of the present invention is that the processed rice product is a processed product in the form of a grain meal of any one of cooked rice, germinated brown rice, rice bran, and high-pressure treated rice.

  The fourth feature of the present invention is that the processed rice product is a processed product in the form of a powdered food such as bread, noodles or rice crackers.

  The fifth feature of the present invention is that the processed rice product has a blood glucose rise inhibitory action.

  The sixth feature of the present invention is to add rice having a weight of at least twice its weight to the polished rice of mutant rice in which the ratio of the short chain of amylopectin to the total amylopectin chain is 20% or less. .

  The seventh feature of the present invention is that the ratio of the amylopectin short chain to the total amylopectin chain is 20% or less by applying a pressure of 10 to 300 atmospheres and then rapidly removing the pressure. The volume of the expanded rice is 3 ml / g to 20 ml / g.

That is, the present invention according to claim 1 is a processed rice product in a grained or powdered form using mutant rice in which the ratio of the short chain of amylopectin to the total amylopectin chain is 5 to 20%.
In the present invention according to claim 2, the degree of glucose polymerization of the amylopectin short chain of the mutant rice is 6 to 12, the ratio of the amylopectin short chain to the total amylopectin chain is 5 to 20%, and the resistant starch content is It is a thing of 5% or more, The processed rice product of Claim 1 characterized by the above-mentioned.
The present invention according to claim 3 is characterized in that the processed rice product is a processed product in the form of a granule of any one of cooked rice, germinated brown rice, rice bran, or high-pressure treated rice. It is a product.
The invention according to claim 4 is the processed rice product according to claim 1 or 2, characterized in that the processed rice product is a processed product in the form of a powdered food of bread, noodles or rice crackers.
The invention according to claim 5 is the processed rice product according to any one of claims 1 to 4, wherein the processed rice product has a blood glucose rise inhibitory action.
The present invention according to claim 6 is to add rice with a weight twice or more of the weight to the polished rice of mutant rice in which the ratio of the short chain of amylopectin to the total amylopectin chain is 5 to 20%. It is the manufacturing method of the rice processed product of the grain-eating form characterized.
In the present invention according to claim 7, the pressure of 10 to 300 atm is applied to the polished rice of mutant rice in which the ratio of the short chain of amylopectin to the total amylopectin chain is 5 to 20%, and then rapidly depressurized. 2. The method for producing a processed rice product according to claim 1, wherein the rice has a porous structure with a specific volume of 3 to 20 ml / g.

(1) According to the present invention, it becomes possible to provide cooked rice, rice bran, germinated brown rice, high-pressure treated rice (retort cooked rice), etc., which are rich in indigestible starch, and diabetic by suppressing an increase in blood sugar level after eating rice It can be expected to prevent such effects.
(2) According to the present invention, it becomes possible to provide bread, noodles, rice crackers, etc. that are rich in indigestible starch, and the blood sugar level after eating rice flour while taking advantage of its deliciousness as a powdered food application and other uses The effect of preventing diabetes and the like can be expected by suppressing the increase in the blood pressure.
(3) According to the present invention, a new application of low-tasting rice with a short amylopectin short chain as a new functional rice processed material is developed.
(4) According to the present invention, a food that can be expected to have health promotion and disease prevention effects such as intestinal regulation by proliferation of useful intestinal bacteria and heart disease prevention by cholesterol reduction is provided.

Hereinafter, the present invention will be described in detail.
In the present invention, lifestyle-related diseases refer to diseases whose onset or disease progression is caused by lifestyle, such as diabetes, hyperlipidemia, and heart disease.

  In the present invention, a food that suppresses an increase in blood glucose after feeding refers to a food that suppresses an increase in the amount of glucose in blood or an increase in insulin after feeding, and is also referred to as a food having a low glisemic index or a low GI food.

The mutated rice in the present invention is artificially mutated by a chemical reagent such as methylnitrosourea (MNU) or N-bis (2-hydroxypropyl) nitrosamine (DHPN) or by physical stimulation such as cobalt-6. This refers to rice whose characteristics are genetically retained.
Such mutant rice has a ratio of amylopectin short chain having a glucose polymerization degree of 6 to 12 to the total amylopectin chain of 20% or less, usually 5 to 20%, for example, EM10, EM16, EM72, EM129, EM189, EM192 etc. are mentioned. These can be obtained from the Mitsuru Sato laboratory at the Graduate School of Agriculture, Kyushu University under proper procedures. If it is less than 5%, the processed rice product becomes too hard to withstand use, which is inappropriate. On the other hand, if it exceeds 20%, the amount of resistant starch is too large, and the object of the present invention cannot be achieved.

The amylose in the present invention refers to a linear polymer in which glucose is polymerized mainly by α-1,4 glycosidic bonds, which is a constituent of starch. The amylopectin in the present invention is a constituent of starch, and a dendritic polymer in which branching by α-1,6 glycosidic bonds is derived from a main chain in which glucose is polymerized by α-1,4 glycosidic bonds. Point to.
Further, the amylopectin short chain in the present invention refers to a short chain length portion having a glucose polymerization degree of 6 to 12 constituting the outside of the amylopectin molecule. The amylopectin short chain can be measured by decomposing starch molecules with a starch debranching enzyme such as isoamylase and then separating and quantifying the molecules based on the difference in molecular weight using an apparatus such as ion chromatography. In the present invention, because BE IIb that branches the amylopectin short chain of starch is deficient, the mutant rice having a ratio of the amylopectin short chain to the whole of 20% or less, usually 5 to 20%, has good processing suitability. It is particularly preferable because it exhibits remarkable indigestibility.

In the present invention, cooked rice, germinated brown rice, rice bran, bread, noodles, rice crackers and the like refer to ordinary processed rice products. These processed rice products are processed rice products that have much less digestible starch than processed rice products that use ordinary high amylose rice as a raw material by using the above-mentioned mutant rice with a short amylopectin short chain. .
For this reason, the rise in blood glucose after eating can be moderated to prevent the onset of diabetes, or the intestinal regulating action and cholesterol lowering effect by promoting the growth of useful intestinal bacteria can be expected.
In the case of processed products in the form of grain meal such as cooked rice, germinated brown rice, rice bran, and high-pressure treated cooked rice, there is a feature that the effect of suppressing the increase in blood sugar becomes more remarkable because digestion is slow. On the other hand, when used in powdered food forms such as bread, noodles, rice crackers, etc., in addition to the effect of suppressing the increase in blood sugar, the taste is also good.

  However, these processed rice products are inherently extremely hard and have a poor taste. However, water of at least twice, usually 2 to 10 times the weight of the mutated rice is added. By cooking, the taste of processed products in the form of grain meal such as cooked rice, germinated brown rice, rice bran, or high-pressure treated rice can be remarkably improved. In the case of normal Japanese rice, the amount of water added during cooking is 1.2 to 1.8 times the weight of the polished rice. In the present invention, the taste of processed rice products using mutant rice as a raw material could be improved by setting the amount of water added to be twice or more, which is different from the conventional amount.

In order to further improve the taste of these processed rice products, pre-treatment or post-treatment such as high-pressure treatment, puffing and enzyme treatment can be added. Examples of high-pressure treatment include processing from retort cooked rice by high-pressure treatment of about 1.2 kg / cm ² to ultra-high pressure processing of 1,000 MPa.
Furthermore, as a material for bread, noodles, rice crackers, etc., the specific volume can be reduced by applying a pressure of 10 atmospheres or more, usually 10 to 300 atmospheres, to the mutant rice with a short short chain of amylopectin and then rapidly removing the pressure. However, by using a puffed rice having a porous structure of 3 to 20 ml / g, the taste and processing suitability of the product can be improved. If the pressure is less than 10 atmospheres, expansion during decompression becomes insufficient and the specific volume becomes less than 3 ml / g, so that only products with poor product taste and processability can be obtained. In addition, if the pressure is suddenly released after applying a pressure of 300 atm or more, the pressure change is too large and the expanded product becomes brittle. On the other hand, if the specific volume exceeds 20 ml / g, the density of rice confectionery products, powders, etc. is too low, so that crushing occurs during distribution and processing, which is inappropriate.

Examples of the enzyme treatment include amylase treatment for decomposing starch, protease treatment for degrading protein, cellulase treatment for degrading cell walls and binding components, and pectinase treatment.
Examples of expansion processing include instantaneous expansion processing by heating in a high-pressure sealed container of about 10 atm and then suddenly releasing to normal temperature and normal pressure, and 20 to 300 atm using a uniaxial or biaxial extruder. Can be mentioned.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

(Example 1) Mutant rice with a short short chain of amylopectin
(1) Rice sample The rice sample is mutated rice EM10, EM129, and EM189, which is a mutant rice that lacks starch branching enzyme II by MNU treatment, as the mother rice of mutant rice, as general japonica rice used. These samples were collected from the Kyushu University Graduate School of Agriculture in order to evaluate the taste characteristics physicochemically in the joint research between the inventors and the Kyushu University Graduate School for four years from 2000 to 2003. This was provided by Hikari Sato Laboratory.
These sampled rice was milled with a test rice huller (manufactured by Satake, THU-35A) and refined to 90% yield with a rice mill for testing (manufactured by Kett Chemical Research Laboratory, Parest) to obtain polished rice. This polished rice was crushed by a cyclone sample mill (manufactured by Udy) to prepare a sample.

The obtained powder sample is immersed in a 0.2% sodium hydroxide aqueous solution at 4 ° C, and washing and centrifugation are repeated until no protein is detected in the supernatant (the absorbance at 280 nm of the supernatant is 0.02 or less). The protein removal treatment was performed.
Next, it was sieved with a 200 mesh metal sieve and washed repeatedly with pure water until the pH became neutral (until the phenolphthalein showed no red color). The crude starch thus obtained was air-dried and pulverized to obtain a powder sample.

  1 cc of water was added to 2 mg of each powder sample, and starch was debranched with isoamylase (manufactured by Seikagaku Corporation). The enzyme reaction was then stopped by the addition of caustic soda. After debranching, the chain length distribution of amylopectin was measured by an ion chromatograph (Nippon Dionex) equipped with a current detector. In addition, the difference in chain length distribution between each mutant rice and Jinnankaze was determined. These results are shown in FIGS.

  The mutant rice used in the present invention has 18% (EM10), 19% (EM129), and 20% (EM189) amylopectin short chain ratios with chain lengths of 6 to 12, compared to 30% of Kimnan style. Was significantly less.

(Example 2) Measurement of RS content (1) Rice samples Rice samples were temperate japonica, Koshihikari, milky queen, Indian rice, Jasmin Rice, Kalijira, Basmati, Indian high amylose rice, Kasalath, LPT123, Saohi, EM10 was used as a mutant rice with a short short chain of Yumeyoku, Hoshiyutaka, and amylopectin as a hybrid between India and India.

(2) Measurement of amylose content and protein content Samples are milled with a test rice grinder (Satake, THU-35A) and polished to a yield of 90% with a test rice mill (Kett Chemical Laboratory, Parest). Got. This polished rice was crushed by a cyclone sample mill (manufactured by Udy) to prepare a sample.
The sample was measured according to the Friano iodine colorimetric method. The calibration curve is a mixture of potato amylose (Sigma, Potato amylose III) and rice amylopectin (degreased and deproteinized glutinous rice powder) in a ratio of 40/60, 30/70, 20/80, 10/90, 0/100 And created. The protein content of the sample powder was obtained by calculating the total nitrogen content by a combustion method (LECO FP-528 type nitrogen analyzer), and multiplying it by a nitrogen protein conversion factor of 5.95 in rice.

(3) Quantification of RS
RS kit was quantified using a Megazyme kit (resistant starch measurement kit). Specifically, it is as follows. A sample (100 mg for rice flour, 200 mg for cooked rice) was supplemented with 4 ml of 0.1 M maleate buffer (pH 6.0) containing pancreatic amylase and amyloglucosidase, and treated at 37 ° C. for 16 hours to digest soluble starch. 4 ml of ethanol was added to a concentration of 50%, mixed, and centrifuged at 1500 × g for 10 minutes to collect the precipitate.
Further, 8 ml of 50% ethanol solution was added to suspend and centrifuge twice. The supernatant of these processes was collected and used for the measurement of soluble starch. 2 ml of 2M KOH was added to the residual starch recovered as a precipitate and suspended in ice for 20 minutes. 8 ml of a sodium acetate buffer solution (pH 3.8) containing amyloglucosidase was added and reacted at 50 ° C. for 30 minutes to decompose the residual starch, and the resulting glucose was colorimetrically determined. The ratio of RS to the total of soluble starch and RS is shown as a percentage.

  When the RS content of rice varieties was compared using rice powder, varieties with higher amylose content such as Kasalath of indica rice tended to have a higher RS content (FIG. 2). However, as is apparent from the figure, RS was about 1% even in Kasalath, which had the highest content. On the other hand, when RS was measured with polished rice and cooked rice for EM10, it showed a remarkably high value of 31% for polished rice and 26% for cooked rice (FIG. 3).

(Example 3) Preparation and measurement of physical properties of cooked rice Various types of rice in which the ratio of the short chain of amylopectin to the total amylopectin chain is 20% or less, that is, polished rice of EM10, EM72, EM129 and EM189, gold of temperate japonica as control sample rice South wind, Indica IR36 polished rice was adjusted to a moisture content of 14.5% ± 0.5% at 70% humidity. 10 g of each of these polished rice samples was weighed into a pudding cup having an outer diameter of 6.0 cm, a bottom diameter of 4.2 cm, and a height of 5.5 cm, 16 ml of pure water was added, and water was absorbed at 25 ° C. for 1 hour. Then, 5 pieces were arranged in an electric rice cooker (Toshiba RC183, Tokyo), 75 ml of pure water was added to the kettle, and the rice was cooked for 20 minutes. After the switch was turned off and steamed for 15 minutes, the lid was opened and the cooked rice sample was transferred from the pudding cup to a glass petri dish, sealed in a plastic bag and allowed to stand at 25 ° C. for 2 hours.
Each of 30 samples of this sample, using a tensipresser (manufactured by Taketomo Denki, My Boy, Tokyo), the method of Okadome et al. (Hiroshi Okadome and 6 others, Journal of Japan Society for Food Science and Technology, vol. 45, pp.398- 407, 1998). The measurement item is the adhesion amount (L3) of the cooked rice surface layer with a compression rate of 25%. The results are shown in Table 1.

Unit: Hardness of surface layer; x1000dyn, stickiness; x1000dyn, adhesion amount; mm
Overall hardness; x1000000dyn, stickiness; x1000000dyn

As shown in Table 1, EM10, EM72, EM129, and EM189, which are mutant rices with a short short chain of amylopectin, were harder and harder than IR36, which is a high amylose rice.
However, when rice was cooked after increasing the amount of water added to 22 ml and absorbing water for 2 hours with respect to 10 g of polished rice, the properties of the cooked rice were remarkably improved, and the cooked rice was soft.

(Example 4) Bread 1 g of sugar was added to 100 ml of lukewarm water (35 ° C.), 8 g of dry yeast was added, and pre-fermented. Next, 210 g of commercially available strong flour is added to 90 g of milled rice flour (EM129) with a short chain of amylopectin as in Example 1, and then mixed with 15 g of sugar, 6 g of salt, 90 ml of milk, 15 g of egg and 15 g of unsalted butter. did. To this, prefermented yeast was added and mixed.
The dough was placed on a plate, kneaded by hand, gathered together when it came out, rolled into a bowl, covered with wrap, and fermented at 30 ° C to 3 volumes. And after confirming that it had fully fermented by the finger test, it rolled up and put into the ball | bowl, covered with the plastic bag, and let it sleep for 30 minutes. The dough was rolled into a sphere and laid for 15 minutes at room temperature over a dry cloth.
The dough was stretched and placed in a bread pan frame coated with shortening and fermented at 35 ° C. for 1 hour. Subsequently, it was baked in an oven at about 200 ° C. for 30 minutes.
On the other hand, as a comparative product, 90 g of normal milled rice for processing and 210 g of commercially available strong flour were mixed and used to produce a bread in the same manner as described above.
Table 2 shows the appearance, physical properties, ingredients, and taste test results of the bread product. In addition, comprehensive evaluation evaluated comprehensively the external appearance taste and the resistant starch content, and it was set as (circle): favorable and X: inferior.

  As shown in Table 2, bread prepared using mutant rice (EM129) having a ratio of 19% of amylopectin short chain to total amylopectin chain according to the present invention had good appearance and texture as bread. It was. In addition, the resistant starch content, which is expected to have functionality, was extremely high at 15.5%.

(Example 5) Noodles As a raw material rice, mutant rice (EM192) in which the ratio of short chain of commercial processing rice and amylopectin to the total amylopectin chain was 18% was used. The yield was refined to 90% using a test rice mill (manufactured by Yamamoto Seisakusho), and a milled rice powder was prepared using an impact mill (manufactured by Udy). Add 150g of the above rice flour to 500g of commercially available medium strength flour, add about 40% water (containing 30g of salt), knead for 15 minutes with a kneader (Arai Seisakusho), kneader (Arai Seisakusho) ) And kneaded the dough three times.
This dough was rolled to a thickness of about 2 mm by a rolling mill (manufactured by Arai Seisakusho), made into a sheet, cut and placed at a low temperature (5 ° C.) overnight to be cured. The cured dough was cut into approximately 2.5 mm with a noodle maker's incisors to make trial noodles.

  Both of these two types of noodles were good in terms of taste. As a result of measuring the indigestible starch content contained in the noodles with a measuring kit of Megazyme, in the case of noodles made with processed rice, RS was only 0.3% per dry matter, but prototyped with EM192 In the case of noodles, the RS was extremely high at 28.9%.

(Example 6) Rice crackers As raw rice, milled rice for commercial processing and EM72 (mutant rice with a small proportion of amylopectin short chain) were pulverized and used as main ingredients. These were mixed in the composition shown in Table 3, 70 g of pure water was added to 100 g and kneaded to make dough balls.

The dough balls were steamed for 15 minutes with a steamer, and then put on for 10 minutes with a household rice cake machine (Tiger rice cake machine, SMK-1800). This steamed dough was wrapped in a plastic film (Saran wrap), stretched to a thickness of 1.5 mm, and punched out with a circular mold.
These round doughs were dried overnight (18 hours) in a constant temperature and humidity chamber at a temperature of 15 ° C. and a humidity of 40%. The dried dough was dried at 180 ° C. for 10 minutes using a hot air dryer (Advantech, FC-610), and then baked at 230 ° C. for 10 minutes to make an unglazed rice cracker.

The specific volume of rice crackers was measured by Yanase et al.'S plant seed replacement method (Yanase Atsushi, Endo Isao, Okuno Motoko, Research Institute for Food Research, No. 42, pp. 1-9, 1983). The texture of rice crackers was evaluated by sensory tests by 12 tasters. Dietary fiber was measured as the weight of non-enzymatic enzyme by AOAC method. Table 3 shows the results of these measurements and evaluations.
The photographs of prototype No. 1 (comparative example) and No. 2 (invention product) are shown in FIG. 4 (A in the figure is the product of the present invention, B is the product of the comparative example, and the top Before the rice cake is baked, the bottom shows after baking.)

Evaluation: ○ Good, X bad

  As shown in Table 3, the rice cracker (sample No. 2) of the present invention had a good texture, was delicious, and the resistant starch was remarkably increased. On the other hand, in the rice confectionery of Comparative Example (No. 1), since the raw material rice was general processing rice, it became a product with less resistant starch.

(Example 7) 粥 Mutant rice (EM10) with few short chains of Kinuhikari and Amylopectin from 2003 Ibaraki Prefecture was used as the sample rice. Using a test rice mill (Yamamoto Seisakusho, YP31), the yield was 90%, and each 100g of polished rice was put into a clay pot, 500g of pure water was added to it, soaked for 1 hour, then it started with high heat and then boiled. Heated to low heat and stopped when the rice grains were fully gelatinized (after about 30 minutes). After steaming for 15 minutes, it was cooled to room temperature. After that, it was frozen in a freezer at −30 ° C. and freeze-dried by a freeze dryer (Ira, FD-1). This was pulverized by a small pulverizer (Milcer manufactured by Iwatani Corporation), and RS was measured. As a result, the Kinuhikari cocoon had an RS content of 0.3%, whereas the EM10 cocoon had an extremely high value of 23%.

(Example 8) Germinated brown rice As raw rice, mutant rice (EM129) with a short chain of Koshihikari and amylopectin from 2004 Ibaraki Prefecture was used. The brown rice sample was immersed in a 0.1% sodium hypochlorite aqueous solution for 30 minutes to sterilize the surface of the brown rice.
Next, after thoroughly washing with pure water to remove sodium hypochlorite, 1 kg of brown rice sample was immersed in 30 L of immersion water controlled at 30 ° C., while replacing the entire amount of immersion water every 24 hours, Soaked for 72 hours to germinate.
The obtained germinated brown rice sample was freeze-dried and then pulverized using a small pulverizer (Milcer manufactured by Iwatani Co., Ltd.), and free amino acids extracted with 8% trichloroacetic acid were measured with an amino acid automatic analyzer (Hitachi Automatic Amino Acid Analyzer 8500). .
As a result, germinated Koshihikari brown rice contained 56 mg / 100 g and germinated EM10 brown rice contained 76 mg / 100 g of γ-aminobutyric acid. The RS measured with the Megazyme kit was 0.2% for germinated Koshihikari brown rice, compared with 32.6% for germinated EM129 brown rice, and the latter contained 163 times more RS.

(Example 9) High-pressure treated rice rice A high-amylose rice produced in Ibaraki Prefecture in 2004, Yume ten-colored rice and amylopectin-mutant rice with a few short chains (EM72) as a raw rice, and a grinding-type rice mill for testing (manufactured by Satake) , TM5) was used to refine the yield to 90%. After putting 20g of these polished rice samples in a plastic bag, adding 35g of pure water and heat-sealing, the autoclave (manufactured by Hirayama Seisakusho, personal clave) was heated at 0.3MPa and 150 ° C for 20 minutes to obtain retort rice. . After cooling, it was frozen at −30 ° C. and freeze-dried with a freeze dryer (Ira, FD-1).
This was pulverized by a small pulverizer (Milcer manufactured by Iwatani Corporation), and RS was measured. As a result, the Yume ten-colored retort cooked rice had an RS content of 1.5%, whereas the EM72 retort cooked rice was a very high value of 10.2%. This high-pressure treated rice was softer than normal cooked rice, and the taste was improved.

(Example 10) Expanded rice As a sample rice, mutant rice EM129 with a short short chain of amylopectin was used, and Nipponbare was used as a comparative sample. Brown rice was refined to a yield of 90% using a test rice mill (Yamamoto Seisakusho, YP31). This was expanded by a 2-axis extruder (TEX38FSS-20AW) made by Nippon Seiko. The operating conditions were a barrel temperature of 180 ° C. and a pressure of 60 atmospheres, and high-temperature and high-pressure extrusion processing was performed using a nozzle with a diameter of 3 mm.
The obtained rice crackers for snacks had specific volumes of 6.5 and 7.8, respectively, and both showed a crispy and good texture. The RS content of the product of the present invention (EM129) was as high as 7.5%, while the product of the comparative example (Nipponbare) was as low as 0.1%.

The rice confectionery product of the present invention was pulverized using a cyclone mill manufactured by Udy, and mixed with commercially available strong flour at a ratio of 3: 7 to make a prototype of bread. 1 g of sugar was added to 100 ml of lukewarm water (35 ° C.), and 8 g of dry yeast was further added for pre-fermentation.
210 g of commercially available strong flour was added to 90 g of the expanded powder of EM129, and 15 g of sugar, 6 g of salt, 90 ml of milk, 15 g of egg and 15 g of unsalted butter were added and mixed. To this, prefermented yeast was added and mixed.
The obtained dough was placed on a plate, kneaded by hand, and gathered together when it became sticky, rolled up, placed in a bowl, covered with wrap, and fermented at 30 ° C to 3 volumes. After a finger test to confirm that it was fully fermented, it was rolled and placed in a bowl, covered with a plastic bag and allowed to sleep for 30 minutes. The dough was rolled into a sphere and laid for 15 minutes at room temperature over a dry cloth. The dough was stretched and placed in a bread pan frame coated with shortening and fermented at 35 ° C. for 1 hour.
Subsequently, it was baked in an oven at about 200 ° C. for 30 minutes. On the other hand, as a comparative control product, 90 g of expanded rice prepared from the above-mentioned Nipponbare and 210 g of commercially available strong flour were mixed and used, and a bread was produced in the same manner as described above.

  Both breads were well fermented and swollen and showed a good taste. The former bread had an RS content of 6.3% and the latter 2.2%. From the viewpoint of the content of resistant starch, the product of the present invention was extremely excellent.

(Example 11) Blood glucose increase inhibitory effect The subjects were 16 healthy persons, 7 males and 9 females. Two sample rice varieties (EM129 and Nipponbare) were polished to a yield of 90% using a test rice mill (Yamamoto Seisakusho, YP31). To 150 g of these polished rice, 180 ml of pure water (Nipponbare) or 320 ml of pure water (EM129) was added and immersed at 25 ° C. for 2 hours. Next, rice was cooked using an electric kettle (Mitsubishi IH Jar Rice Cooker NJ-DS06 type). Each subject was allowed to eat 100g of cooked rice, and a total of 5 puncture assisting devices (Raclette, Sanwa Chemical Laboratory Co., Ltd.) before taking the rice and after 30 minutes, 60 minutes, 90 minutes, and 120 minutes. )), Blood was collected from the test subject, and blood glucose level in plasma was measured by enzymatic method. As a result of averaging the blood glucose levels after 16 meals, the blood sugar level increased more slowly after the EM129 rice was sampled than when the Japanese fine rice was sampled.

  According to the present invention, a processed rice product having a high resistant starch and a method for producing the same are provided. As a raw material for this processed rice product, low-taste rice with a short amylopectin short chain is used, so that the use for processed rice product having new functionality is developed.

(a)-(d) shows the chain length distribution of the mutant rice which is the rice sample in Example 1, (e)-(g) shows the chain length distribution of each mutant rice and control rice (Ginnan style). FIG. The comparison between the resistant starch content (%) of the control rice (milled rice flour) in Example 2 is shown among varieties. The resistant starch content (%) of the mutant rice (milled rice flour or cooked rice) which is the rice sample in Example 2 is shown. In the photograph of the rice cracker prototype of Example 5, A is the product of the present invention, and B is the product of the comparative example.

Claims (7)

  Processed rice products in the form of grain meal or flour meal using mutant rice in which the ratio of short chain of amylopectin to total amylopectin chain is 5 to 20%.   In the mutant rice, the degree of glucose polymerization of the amylopectin short chain is 6 to 12, the ratio of the amylopectin short chain to the total amylopectin chain is 5 to 20%, and the resistant starch content is 5% or more. The processed rice product according to claim 1.   3. The processed rice product according to claim 1, wherein the processed rice product is a processed product in the form of a granule of any one of cooked rice, germinated brown rice, rice bran, or high-pressure processed rice.   3. The processed rice product according to claim 1, wherein the processed rice product is a processed product in a powdered form of bread, noodles or rice crackers.   The processed rice product according to any one of claims 1 to 4, wherein the processed rice product has an effect of suppressing an increase in blood sugar.   A processed grain-shaped rice product characterized by adding water of at least twice the weight to the polished rice of mutant rice in which the ratio of short chain of amylopectin to total amylopectin chain is 20% or less. Production method. A specific volume of 3 to 20 ml / g is obtained by applying a pressure of 10 to 300 atmospheres to the polished rice of mutant rice in which the ratio of amylopectin to the total amylopectin chain is 20% or less. The method for producing a processed rice product according to claim 1, wherein the expanded rice has a porous structure.