JP6534528B2 - Rice with high resistant starch content and method for producing the same - Google Patents

Description

  The present invention relates to resistant starch-rich rice and a method for producing the same. More specifically, the present invention relates to rice in which the content of resistant starch is increased in the state of milled rice, and the reduction due to cooking is suppressed, and a method for producing the same.

  In recent years, for the purpose of preventing lifestyle-related diseases such as obesity, diabetes, hyperlipidemia, hypertension and the like, various foods such as low calorie, limited carbohydrates and high dietary fiber content have been developed.

  Rice and its processed food are familiar foodstuffs for Japanese, but the main component is starch. Starch is generally easy to digest, but there is a partially resistant fraction, which is called resistant starch (RS). Resistant starch (hereinafter sometimes abbreviated as “RS”) is said to work in the same way as dietary fiber in the living body, and it has been reported that the effect of suppressing blood sugar rise and intestinal environment improvement effect etc. There is.

  Generally, although the RS content contained in rice is 1% or less, mutated rice in which the amylopectin branching enzyme IIb (BEIIb) is deficient or the enzyme activity is reduced (hereinafter, “super hard rice” May contain a large amount of RS, which is about 18% for "Chikishikoku 85", which is a kind of super hard rice, and about 25% for "EM10". There is. Thus, super hard rice contains much more RS than general rice, but depending on the way of cooking, the content of RS may decrease. Since rice usually eats cooked food, it is required that the RS content be as high as possible even after cooking.

  So far, research has been conducted to increase the content of resistant starch in starch by starch processing and the like. For example, a pretreatment step in which fermentation treatment with lactic acid bacteria or enzyme treatment with proteolytic enzyme is performed, a surface treatment step in which only the surface is gelatinized temporarily by steam heating, and then cooled and dried; A method for producing diet rice comprising a resistant starch forming step of leaving moist heat treatment in a high humidity atmosphere (Patent Document 1), containing uncooked rice with lactic acid bacteria having sucrose and polysaccharide polysaccharide generating ability Soak in the preparation liquid for fermentation treatment, remove the polysaccharide thickener produced by fermentation in a state where it adheres to or impregnates the rice, drain the rice, then steam the raw rice, and then cool and loosen it Method to make a part of starch a resistant starch by performing moist heat treatment which heats the treated processed rice which has been done and sealed in a sealed state further (patent document 2), high amylose corn A method of contacting a starch with hot water having a temperature of 160 to 260 ° C. and a pressure higher than the saturated vapor pressure of the temperature (Patent Document 3), fractionating high amylose starch having an amylose content of at least 85% from corn according to particle size There is a method of obtaining a starch fraction having an increased resistant starch content (Patent Document 4). Also, as an example examined from the viewpoint of heat treatment resistance of resistant starch, a method of acid treating an amylose-rich starch having an amylose content of 40% or more in an aqueous inorganic acid solution (Patent Document 5), etc. is reported There is. However, all of these methods require multiple steps and complicated processing steps, and are not necessarily satisfactory for heat treatment resistance.

Patent 4757419 gazette Patent No. 4038450 Patent 5322232 Patent 3628690 Patent No. 4482611

  Therefore, an object of the present invention is to provide a method for easily and easily producing rice and processed rice products with high resistant starch content, while suppressing a decrease in resistant starch content after cooking of super hard rice.

  As a result of intensive studies to solve the above problems, the present inventors add fats and oils to super hard rice and perform steam heat treatment to increase resistant starch content in the milled state of super hard rice. It has been found that it is possible to suppress the decrease in the resistant starch content after cooking, and complete the present invention.

Accordingly, the present invention includes the following inventions.
(1) Resistant starch high content rice obtained by adding an oil and fat to a mutant rice in which an amylopectin branching enzyme (BEIIb) is deficient or in which the enzyme activity is reduced and performing steam heat treatment.
(2) Resistant starch high content rice as described in (1) whose resistant starch content is 15 weight% or more in a rice milling state and whose resistant starch content after rice cooking is 6 weight% or more.
(3) The resistant starch high content rice as described in (1) or (2) whose addition amount of the fats and oils with respect to the said mutant rice is 0.3 to 10 weight%.
(4) Resistant starch high content rice in any one of (1)-(3) whose temperature of the steam heat processing with respect to the said mutant rice is 80-250 degreeC.
(5) Resistant starch high content rice in any one of (1)-(4) whose time of the steam heat processing with respect to the said mutant rice is 2 to 120 minutes.
(6) Rice processed food which processed resistant starch high content rice in any one of (1)-(5).
(7) Production of resistant starch-rich rice comprising the steps of adding fats and oils to mutant rice in which the amylopectin branching enzyme (BEIIb) is deficient or in which the enzyme activity is reduced, and a step of steam heat treatment Method.
(8) A heat-resistant starch content of the mutant rice is heated by adding an oil to a mutant rice which is deficient in the amylopectin branching enzyme (BEIIb) or in which the enzyme activity is reduced, and subjected to steam heat treatment. How to suppress the decrease due to cooking.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to increase the resist tanto starch content in the milled state of superhard rice by a simple and easy means, the fall of the resist tanto starch content after cooking can be suppressed. The rice containing the high content of the resist tanto starch provided by the present invention and the rice processed food containing the same contain a large amount of the resist tanto starch which is a water-insoluble dietary fiber which is not digested and absorbed, so the postprandial blood glucose rise is moderated to cause diabetes. Can be expected to have an effect of preventing the onset of intestinal inflammation, or an intestinal regulation effect or cholesterol lowering effect by promoting the growth of useful bacteria in the intestine, and a satiety feeling can be obtained, which is useful for preventing obesity.

  The resistant starch-rich rice of the present invention is subjected to steam heat treatment by adding fats and oils to mutant rice (super hard rice) which is deficient in amylopectin branching enzyme (BEIIb) or in which the enzyme activity is reduced. It is processed rice obtained by

  According to the present invention, there is also provided a method of producing the above-mentioned resistant starch-rich rice. The said manufacturing method should just include the process of adding fats and oils to said super-hard rice, and the process of performing steam heat processing at least, and you may perform other processes, such as a milled rice, grinding, and a blend. The fat and oil addition step is performed before the steam heat treatment step.

  The super hard rice serving as the raw material rice is a mutated rice having a short amylopectin short chain due to a defect in BEIIb that branches amylopectin short chains of starch or a decrease in the activity of the enzyme, for example, amylopectin short chains It refers to mutant rice having a ratio of 5 to 20% to the total amylopectin chain. BEIIb deficiency is artificially caused by chemical reagents such as methyl nitrosoureas (MNU) and N-bis (2-hydroxypropyl) nitrosamines (DHPN) or by physical stimuli such as cobalt 6, and the enzyme activity of BEIIb is completely Not only the defect but also the significant reduction of the enzyme activity. As super hard rice, for example, EM10, Kona no Mai, Amilomochi, Chikushi flour No. 85, etc. are known. In the present invention, these super hard rices may be used alone or in combination of two or more. Chikushi flour No. 85 is a super hard rice line owned by Fukuoka Prefectural Agriculture and Forestry Research Institute.

  The fats and oils added to super hard rice in the present invention are generally used as edible fats and oils and are not particularly limited as long as they do not interfere with the effects of the present invention, for example, rapeseed oil, cottonseed oil, soybean oil, sesame oil, safflower Flower oil, sunflower oil, corn oil, rice oil, grape oil, peanut oil, olive oil, camellia oil, palm oil, palm kernel oil, palm oil, vegetable oil such as cocoa butter, beef tallow, pork fat, chicken oil Animal fats and oils such as fish oil and egg yolk oil, mixed oils of these fats and oils, processed fats and oils (for example, treated with one or more kinds selected from hydrogenation, transesterification, and fractionation) Shortening, margarine, etc.) can be used. Among them, vegetable fats and oils which are liquid at normal temperature are preferable, and refined oils having high refining degree and refined oils with little taste and smell and refined oils which are dewaxed refined oils are preferable. The salad oil includes rapeseed salad oil, cotton seed salad oil, soybean salad oil, sesame salad oil, safflower salad oil, sunflower salad oil, corn salad oil, corn salad oil, rice salad oil, and grape salad oil, which are defined by the JAS standard. These fats and oils can be used combining 1 type or 2 types or more.

  The amount of fat added to super hard rice is 0.3% by weight or more, preferably 1.0% by weight or more, and the upper limit is 10.0% by weight or less from the viewpoint of the effect on flavor and workability. Is preferred. The addition of fats and oils to super hard rice may be carried out by stirring and mixing a predetermined amount of fats and oils into super hard rice at one time, or adding predetermined amounts of fats and oils while dividing and mixing several times You may do by The method of adding fats and oils to super hard rice is not particularly limited as long as the fats and oils can be uniformly applied to the surface of super hard rice, and there is no particular limitation. It can be done by law. Moreover, as a mixing apparatus, the drum type mixer for foodstuffs, a vertical mixer, a ribbon mixer etc. can be used.

  After adding fats and oils to super hard rice, steam heat treatment is performed. Steam heating is a method of heating an object under a high humidity atmosphere, for example, an atmosphere with a humidity of 80% or more, using hot water, saturated steam, superheated steam, reduced pressure (vacuum) steam or the like as a heat medium. Steam heating may be performed by bringing the heat medium into direct contact with the object, or the object may be heated indirectly through a heat exchanger. The heating may be performed under normal pressure or under pressure. As specific conditions for steam heating, the temperature is 80 ° C. or more, preferably 90 ° C. or more, more preferably 100 ° C. or more, but the upper limit is, for example, 250 ° C. or less from the viewpoint of workability and color tone preferable. The time is 2 minutes or more, preferably 10 minutes or more, more preferably 20 minutes or more, but from the viewpoint of workability and color tone, the upper limit is preferably 120 minutes or less. If the time is less than 2 minutes, the desired effect can not be obtained, which is not preferable. These conditions of temperature and time are only examples and can be changed as appropriate in relation to each other. Further, steam heating in the present invention may be carried out using a continuous or batch type steamer (steamer), an autoclave or the like.

  The present invention in which the resistant starch content in the milled rice state is increased and the reduction in the resistant starch content after cooking is suppressed as compared with the raw super hard rice by the addition of the above-described fat and oil and the steam heat treatment. It is possible to obtain rice with high resistant starch content. Here, "cooking" includes cooking such as "cook", "boil", "bake", "boil", "steam", "fry", and "fry".

  The resistant starch-rich rice of the present invention is characterized by having a resistant starch content of at least 15% by weight in a milled rice state and a resistant starch content after rice cooking of at least 6% by weight. In the present invention, the "resistant starch (RS) content" refers to a value according to the resistant starch measurement method of AOAC (Association of Analytical Chemists) official method 2002.02.

  The present invention also provides processed rice food. The processed rice food in the present invention refers to the above-mentioned resistant starch-rich rice, or a food produced using rice powder obtained by crushing the same, and includes, for example, rice, noodles, breads, confectionery and the like. The rice flour can be obtained by using conventional resistant milling methods such as body milling, roll milling, stone milling, air flow milling, high-speed rotary impact milling alone or in combination with the above-mentioned resistant starch-rich rice. Cooked rice means rice cooked with the above-mentioned resistant starch-rich rice and cooked with other ingredients and seasonings, and includes white rice, salmon, risotto, pilaf, fried rice, cooked rice, risotto and the like. Further, these cooked rices may be ones that are distributed at normal temperature, those that are refrigerated and those that are frozen and distributed. Moreover, what passed through the process of retort sterilization may be that in which preservability was improved. The noodles may be any noodles prepared from noodle dough containing the above-mentioned rice flour, and examples thereof include udon, soba, Chinese noodles, spaghetti, macaroni, skin of wonton, skin of eggplant and the like. The bread may be any bread obtained by baking, frying, steaming or the like a dough prepared by adding the above-mentioned rice flour and other ingredients and water and mixing them, for example, bread, Examples include hearts breads, rolls, danishes, croissants, various confectionery and sugar beet breads, pizzas, and steamed breads. As the confectionery, any confectionery processed by baking, frying, steaming or the like may be used, for example, cake, donut, castella, pie , Waffles, scones, biscuits, cookies and the like.

  These processed rice products can be manufactured according to the usual manufacturing method of each food except using the above-mentioned resistant starch high content rice or the rice flour which grind | pulverized this as a raw material. These processed rice foods also have the above-mentioned resistant starch-rich rice as a raw material, and thus become processed rice foods having a higher resistant starch content than conventional processed rice foods made of rice.

  Hereinafter, the present invention will be more specifically described by way of examples, but these examples do not limit the present invention. In the following examples, the concentration indication is indicated by "%", and "%" means "% by weight".

(Reference example) RS content of untreated rice
(1) Preparation of Test Sample As a rice sample, “Hinohikari” was used as general japonica rice, and “Chikushi flour No. 85” and “EM10” were used as super hard rice. These rice samples were polished with a rice milling machine to make "Hinohikari" 90% of the milled rice, and "Chikushi flour No. 85" and "EM 10" were milled to 85% of the milled rice to obtain milled rice. The obtained Hinohikari milled rice, Chikushi flour No. 85 milled rice, and EM10 milled rice were ground with a grinder with a screen of 1 mm, respectively, to prepare test samples.

(2) Measurement of RS Content To 100 mg of a test sample, 4 ml of 0.1 M maleate buffer (pH 6.0) containing pancreatic amylase and amyloglucosidase was added and reacted at 37 ° C. for 16 hours to digest digestible starch. Thereafter, 4 ml of ethanol was added to achieve a 50% concentration, mixed, and centrifuged at 1500 × g for 10 minutes to collect a precipitate. Furthermore, 8 ml of 50% ethanol solution was added, and the operation of suspending and centrifuging was repeated twice. To the residual starch recovered as a precipitate, 2 ml of 2 M potassium hydroxide was added and suspended in ice for 20 minutes. After suspension, 8 ml of sodium acetate buffer (pH 3.8) containing amyloglucosidase is added and reacted at 50 ° C. for 30 minutes to decompose residual starch to glucose, and RS content is determined by performing colorimetric determination of generated glucose. It was measured. The results are shown in Table 1.

  As shown in Table 1, the RS contents of Hinohikari milled rice, Chikushi flour No. 85 milled rice, and EM10 milled rice were 0.6%, 18.7%, and 24.6%, respectively.

(Comparative Example 1, Examples 1 and 2) Confirmation of increase in RS content of milled rice by addition of fat and oil and steam heat treatment Add predetermined amount of salad oil shown in Table 2 to Hinohikari milled rice, Chikushi flour No. 85 milled rice, EM10 milled rice After heat treatment, steam pretreatment (temperature 100 ° C.) was performed for 60 minutes to prepare test samples (Comparative Example 1, Examples 1 and 2). The RS content of each of these test samples was measured in the same manner as in Reference Example (2). The results are shown in Table 2.

  As shown in Table 2, the increase in RS content was not seen in Hinohikari (Comparative Example 1) of general Japonica rice compared to untreated rice (Reference Example 1) due to salad oil addition and steam heat treatment In the super hard rice powder No. 85 (Example 1) and EM 10 (Example 2), the RS content was increased compared to the respective untreated rice (Reference Examples 2 and 3). From the above results, it has been confirmed that the addition of fats and oils and steam heat treatment increase the RS content itself in the milled rice of super hard rice.

(Comparative Examples 2 to 5, Example 3) Confirmation of inhibitory effect of RS reduction by cooking rice In order to confirm the reduction inhibitory effect of RS content by cooking (cooking) and the reduction of RS content by the processing of the present invention, cooking is performed. Measurement of RS content in rice was performed. Pretreatment shown in Table 3 was performed before rice cooking using Chikushi flour No. 85 milled rice. When mix | blending a salad oil, it pre-processed, after adding and mixing a predetermined amount of salad oil to a milled rice.

  After soaking rice cake powder No. 85 polished rice in water at the compounding amount shown in Table 1 for 1 hour, use a vacuum pot pressure IH jar “exquisitive cooking” NP-RD05-NL (象), it is normal to use I cooked rice in the course. Cooked rice was rapidly frozen at -40.degree. C., freeze-dried and ground in a grinder with a 1 mm screen to prepare a test sample. The RS content of each of these test samples was measured in the same manner as in Reference Example (2). The results are shown in Table 3.

  As shown in Table 3, in the test sample (Example 3) in which the rice subjected to steam heat treatment for 60 minutes after cooking the salad oil was cooked (Example 3), it was confirmed that the decrease in RS content after cooking was suppressed. On the other hand, in the test sample (comparative example 3) in which the rice subjected to steam heat treatment without blending with the salad oil was cooked (Comparative Example 3), the decrease in RS content was somewhat suppressed, but the inhibitory effect was as good as blending with the salad oil. Was not seen. Moreover, in the test sample (comparative example 4) which cooked the rice which performed only heating processing with a frying pan, and the test sample (comparative example 5) which cooked the rice which added only salad oil, suppression of a reduction in RS content Was not seen and was almost the same as untreated rice (Comparative Example 2).

(Comparative Examples 6 to 7) Confirmation of Effect on Rice Other than Super Hard Rice Using Hinohikari as general japonica rice in place of the fine powder No. 85, according to the pretreatment or the compounding amount shown in Table 4 (Comparative The test sample was prepared in the same manner as in Examples 2 to 5 and Example 3). The RS content of each of these test samples was measured in the same manner as in Reference Example (2). The results are shown in Table 4.

  As shown in Table 4, in Hinohikari, no change in RS content due to addition of salad oil and steam heat treatment was observed (Comparative Example 7), and was almost the same as untreated rice (Comparative Example 6).

(Comparative Example 8, Examples 4 to 8) Influence of the Addition Amount of Fats and Oils The amount of salad oil to be adjusted to the milled rice (Chikushi flour No. 85) was changed in the range of 0.2 g to 9.0 g as shown in Table 5; Pre-treatment of steam heat treatment (temperature 100 ° C.) was performed for a minute. Next, after immersing the milled rice after pre-treatment in water with the compounding amount shown in Table 1 for 1 hour, it cooked in the same manner as in (Comparative Examples 2 to 5, Example 3) to prepare a test sample. The RS content of each of these test samples was measured in the same manner as in Reference Example (2). The results are shown in Table 5.

  As shown in Table 5, the reduction inhibitory effect of RS content was seen by adding 0.5 g (0.3%) or more of salad oil with respect to 150 g of milled rice (Examples 4-8).

(Examples 9 to 14) Influence of Types of Fats and Oils After blending olive oil, sunflower oil, rice oil, safflower oil, sesame oil, shortening into milled rice (Chikushi flour No. 85), steam heat treatment (temperature for 60 minutes) The pretreatment was performed at 100.degree. Next, after immersing the milled rice after pre-treatment in water with the compounding amount shown in Table 1 for 1 hour, it cooked in the same manner as in (Comparative Examples 2 to 5 and Example 3) to prepare a test sample. The RS content of each of these test samples was measured in the same manner as in Reference Example (2). The results are shown in Table 6.

  As shown in Table 6, when any of olive oil, sunflower oil, rice oil, sesame oil, safflower oil, shortening oil was used, the same effect as that of salad oil was observed in suppressing the decrease in RS content (implementation Examples 9-14).

(Comparative example 9, Examples 15 to 20) Effect of steam heat treatment time After soaking salad oil in milled rice (Chikushi flour No. 85), steam heat treatment was performed in a range of 1 minute to 120 minutes as shown in Table 7. (Temperature 100 ° C.) was performed. Next, after immersing the milled rice after pre-treatment in water with the compounding amount shown in Table 1 for 1 hour, it cooked in the same manner as in (Comparative Examples 2 to 5 and Example 3) to prepare a test sample. The RS content of each of these test samples was measured according to the method described in Reference Example (2). The results are shown in Table 7.

  As shown in Table 7, the effect of suppressing the decrease in RS content was observed by performing the steam heat treatment for 2 minutes or more, and more preferable results were obtained by performing the heat treatment for 20 minutes or more (Examples 15 to 20). In one minute, the reduction inhibitory effect of RS content was low.

(Comparative Examples 10 to 12 and Examples 21 to 23) Confirmation of effects other than cooked rice In order to confirm the effects of processed rice food, a sponge cake using rice flour of No. 85 powder, steamed bread, udon noodles It prepared and measured RS content. For rice flour, rice flour (comparative examples 10 to 12) not subjected to pretreatment and salad oil were added by 1% to rice flour, and then rice flour treated with steam heat treatment (temperature 100 ° C.) for 60 minutes (implementation Two types of examples 21 to 23) were used.

<Sponge cake>
The sponge cake was produced by the following composition and process. The proportion of rice flour in the sponge cake is 27%.

(Blended)
Rice flour 100 parts by weight Granulated sugar 120 parts by weight Whole eggs 150 parts by weight Water 15 parts by weight

(Manufacturing method)
Granulated sugar and whole eggs were mixed at a medium speed for 6 minutes with a paddle mixer (manufactured by Dalton Co., use a whipper), and rice flour was added and mixed gently. Subsequently, 350 g of the dough was poured into a 6-inch baking mold and baked at 170 ° C. for 28 minutes.

<Steamed bread>
Steamed bread was produced by the following composition and method. The proportion of rice flour in steamed bread is 42%.

(Blended)
70 parts by weight of rice flour 30 parts by weight of wheat flour 60 parts by weight of granulated sugar 7 parts by weight of baking powder 90 parts by weight of water

(Manufacturing method)
Rice flour, flour, granulated sugar, baking powder, water were mixed by hand mixing 100 times using a whipper. Subsequently, 70 g of dough was poured into No. 13 shallow-mouth glassine and steamed at 100 ° C. for 15 minutes.

<Udon>
Udon was produced by the following composition and manufacturing method. The proportion of rice flour in udon is 85%.

(Blended)
Rice flour 85 parts by weight Gluten 15 parts by weight Salt 1 part by weight Water 45 parts by weight

(Manufacturing method)
Rice flour, gluten, and a saline solution were mixed at a medium speed for 10 minutes with a paddle mixer (manufactured by Kanto Mixing Industry Co., Ltd., using a beater), and compounding was performed three times. After aging for 1 hour, rolling was performed 3 times, and the final thickness of the noodle band was 1.4 mm, and cut with a # 10 (corner) cutting edge.

  The RS contents of the sponge cake, steamed bread and udon prepared were measured in the same manner as in the case of cooked rice. The results are shown in Table 8.

  From Table 8, also in processed rice food other than cooked rice, a similar effect was confirmed for suppressing the decrease in RS content due to heating and cooking.

INDUSTRIAL APPLICABILITY The present invention can be used in the field of producing processed rice products such as rice or rice flour, cooked rice, noodles, breads and confectionery products using these.

Claims (6)

Amylopectin branching enzyme (BEIIb) deficient, or, for the mutated rice the enzyme activity decreased by adding oil 0.3 to 10% by weight, obtained by performing a steam heat treatment, AOAC Official Method Resistant starch content measured in 2002.02 is higher in resistant starch content than in the untreated mutant rice, and the resistant starch content is 15% by weight or more in the state of polished rice And, resistant starch high content rice whose resistant starch content after cooking is 6% by weight or more . The resistant starch high-containing rice according to claim 1, wherein the temperature of steam heat treatment for the mutant rice is 80 to 250 ° C. The resistant starch high content rice of Claim 1 or 2 whose time of the steam heat processing with respect to the said mutant rice is 2 to 120 minutes. A processed rice food, wherein the resistant starch high content rice according to any one of claims 1 to 3 is processed. Amylopectin branching enzyme (BEIIb) deficient, or comprises adding an oil 0.3 to 10 wt% for the mutated rice the enzyme activity decreased, the step of performing a steam heat treatment, AOAC Official Method of producing resistant starch-rich rice, wherein the resistant starch content measured by the method 2002.02 is 15% by weight or more in the state of milled rice, and the resistant starch content after cooking is 6% by weight or more . Amylopectin branching enzyme (BEIIb) deficient, or, for the mutated rice the enzyme activity decreased by adding oil 0.3 to 10 wt%, by performing the steam heating treatment, wherein the mutation rice A method for suppressing the decrease in resistant starch content by cooking.