JP4570543B2 - Rice quality improver - Google Patents

Description

  The present invention relates to a rice quality improving agent. More specifically, the present invention provides a rice quality improver (a loosening improver) having an action of improving the loosening by preventing or suppressing the binding between the rice grains, or imparting gloss or gloss to the surface of the rice. It relates to a rice quality improving agent (gloss imparting agent) having an action. Furthermore, this invention relates to the rice which was excellent in the looseness (spreading property) or glossiness (luster) by processing with these rice quality improvement agents, and its manufacturing method. Preferred examples of the rice targeted by the present invention include cooked cooked rice, frozen cooked cooked rice (including frozen cooked cooked rice), and sterile cooked cooked rice (including cooked cooked cooked rice).

  In recent years, many processed rice for business use such as bento and rice balls has been sold at supermarkets and convenience stores, etc. When mass-producing these processed rice, it is easy to loosen the cooked rice Various studies have been made to prevent adhesion to the machine. As such a method, for example, a method in which an O / W emulsion containing diglycerides of saturated fatty acids in the oil phase is blended at the time of cooking or cooking, or added to the cooked rice after cooking or cooking (see, for example, Patent Document 1) is proposed. Has been.

  However, according to this method, the quality of the processed cooked rice is deteriorated from the viewpoint that the improvement effect is insufficient, the flavor is affected, there is a coloring problem such as burning or browning. And there is a problem that the process becomes complicated.

Conventionally, as a method for improving cooked rice, a method for improving the taste quality (crisp, aroma, color, appearance (glossy), moisture storage) of trehalose by adding trehalose, for example, see Patent Document 2), rice cooking By blending pectin before or after cooking rice, it is delicious as plump and has a moderately sticky texture, and a method for producing glossy cooked rice (for example, see Patent Document 3). A method for producing frozen cooked rice having a good appearance such as gloss and tellurization by blending non-reducing and / or reducing oligosaccharides having a degree of polymerization to prevent aging during cold thawing (for example, see Patent Document 4) Has been proposed.
JP-A-5-316971 JP-A-7-250632 JP-A-10-313800 JP-A-6-141797

  The present invention has been developed in view of such circumstances, and is an agent for improving the quality of rice (rice quality improving agent), specifically, preventing rice grains from binding to each other in a dumpling form or An object of the present invention is to provide an agent that suppresses and improves the looseness of rice (a loosening improver), or an agent that gives gloss (gloss) to rice grains (a gloss imparting agent). Furthermore, the present invention uses such a rice quality improver (a loosening improver, a luster imparting agent), so that the rice grains are prevented from binding and forming a dumpling, and the looseness is improved, or the surface. It is an object of the present invention to provide a glossy rice and a method for preparing the same.

  As a result of intensive studies to improve the quality (rice quality) of the above-mentioned rice, the present inventors have found that hydroxypropyl cellulose, or hydroxypropyl cellulose, and water-soluble hemicellulose are 1: 10-10. : (1) Between rice grains by blending the improver containing at a ratio of 1 (weight ratio) into the raw material of rice to produce rice, or by treating heat-treated cereals such as cooked rice with a solution containing these It was found that the loosening of rice can be improved by preventing and suppressing the binding and dumpling, and (2) the surface of the rice grain can be given gloss.

The present invention has been completed based on such findings and has the following aspects.
Item 1. A rice quality improver comprising hydroxypropylcellulose.
Item 2. Item 2. The rice quality improver according to item 1, further comprising water-soluble hemicellulose, wherein the ratio of hydroxypropyl cellulose to water-soluble hemicellulose is 1:10 to 10: 1 (weight ratio). .
Item 3. Item 3. The rice quality improver according to Item 1 or 2, which is a loosening improver.
Item 4. Item 3. The rice quality improving agent according to Item 1 or 2, which is a gloss imparting agent.
Item 5. Item 3. The rice quality improver according to Item 1 or 2, which is a non-sticking agent.
Item 6. Item 3. The rice quality improving agent according to item 1 or 2, which is a texture improving agent (texture deterioration inhibitor).

  Item 7. Item 9. A rice containing the rice quality improving agent according to any one of Items 1 to 6.

Item 8. The loosening improver described in Item 3 is mixed with the rice raw material to prepare rice, or the heat-treated cereal is processed using the loosening improver described in Item 3 to improve rice loosening Method.
Item 9. A method for polishing rice, characterized in that the luster imparting agent described in item 4 is blended with rice ingredients to prepare rice, or heat-treated cereals are processed using the luster imparting agent described in item 4.
Item 10. A method for preventing the burning of rice, comprising preparing the rice by blending the non-sticking agent according to Item 5 into a rice raw material, or treating the heat-treated cereal with the non-burning agent according to Item 5.
Item 11. Item 7. A method for suppressing deterioration of rice texture over time, comprising preparing the rice by blending the texture improving agent (texture deterioration inhibitor) described in Item 6 into a rice raw material.

Item 12. The loosening improver characterized in that the loosening improver described in item 3 is blended with rice ingredients to prepare rice, or the heat-treated cereal is processed using the loosen improver described in item 3. A method for producing rice.
Item 13. The gloss imparting agent described in Item 4 is mixed with rice ingredients to produce rice, or heat-treated cereals are processed using the gloss imparting agent described in Item 4, Production method.
Item 14. The non-sticking agent characterized in that the non-sticking agent described in Item 5 is mixed with rice ingredients to prepare rice, or the heat-treated cereal is processed using the non-sticking agent described in Item 5. A method for producing rice.
Item 15. Item 11. A method for producing rice in which deterioration of the texture over time is suppressed, comprising preparing the rice by blending the texture improving agent (texture deterioration inhibitor) described in Item 6 into a rice raw material.

  According to the rice quality improving agent (freezing improving agent) of the present invention, it is possible to prevent the rice grains from binding to each other and form a dumpling, and improve the looseness of the rice. In particular, according to the rice quality improving agent (freezing improver) of the present invention, a good freezing improving effect can be exhibited even in a cold state or a frozen state. Moreover, according to the rice quality improving agent (gloss imparting agent) of the present invention, gloss can be imparted to the rice grains. In particular, according to the rice quality improving agent (gloss imparting agent) of the present invention, not only when the rice is warm, but also when it is in a cold state, a good glossing effect can be exhibited.

  The rice targeted by the present invention is obtained by heat-treating cereals [rice (including Uruchi rice and glutinous rice), barley, buckwheat, rice bran, rice bran, etc.]. Preferably, the rice is a heat-treated rice. Although it does not restrict | limit especially here as heat processing, Arbitrary heat processing which gelatinizes cereal starch, such as cooking, steaming, oil-cooking, boiling, stir-fry, high-pressure processing, or electromagnetic wave processing, can be mentioned. Preferably it is cooking rice. The rice targeted by the present invention includes a product obtained by subjecting the cereal to a heat treatment (a gelatinization treatment) or a product processed (cooked) together with the heat treatment. Specifically, in addition to white rice; red rice, rice bran, mixed rice, rice balls, rice bowl, curry rice, sushi rice (including nigiri sushi, roll sushi, chirashi sushi), fried rice, pilaf, doria, risotto, rice cake, miscellaneous rice And cooked rice such as Ochazuke. These rice is not particularly limited in its storage or distribution form, and may have any form of normal temperature, chilled state or frozen state. In addition, the rice targeted by the present invention may be packaged according to each of the above storage / distribution forms. For example, as rice that is stored and distributed at room temperature, aseptically packaged rice, retort-treated rice, etc. Can do.

(1) Rice quality improving agent containing hydroxypropyl cellulose The rice quality improving agent of the present invention is characterized by containing hydroxypropyl cellulose. According to the rice quality improving agent of the present invention, as described above, it is possible to improve the looseness and dispersibility of the rice grains by preventing or suppressing the rice grains from binding and forming a dumpling. In particular, the rice quality improving agent of the present invention containing hydroxypropylcellulose is excellent in that it can exhibit good loosening properties even when the rice is cold or frozen. In addition, according to the rice quality improving agent of the present invention, gloss or gloss can be imparted to the surface of the rice grain. Freshly cooked rice grains are naturally shiny, but when they cool, they gradually disappear. In this respect, the rice quality improving agent of the present invention containing hydroxypropylcellulose is excellent in that it can exhibit a good polishing effect even when the rice grains are in a cold state.

  Moreover, the rice quality improving agent of this invention can prevent the browning of the rice by scorching by mix | blending simultaneously with a rice raw material at the time of heat processing. For this reason, it is possible to prevent product loss due to scorching and increase the productivity of rice. From this point, the rice quality improving agent of the present invention can also be used as a non-sticking agent.

  Hydroxypropyl cellulose used in the present invention is a nonionic substance obtained by reacting with an etherifying agent such as propylene oxide after treating cellulose (pulp), which is widely present in nature, with sodium hydroxide. It is a water-soluble cellulose ether. Although it does not restrict | limit especially as a viscosity of a hydroxypropyl cellulose, As a viscosity at the time of room temperature (25 degreeC) at the time of preparing to 2 weight% aqueous solution, about 1-100,000 mPa * s can be mentioned (measurement conditions; BL type) (Rotational viscometer, rotor No. 1 to 4, rotation speed 6 rpm, 25 ° C.). It is preferably 1 to 10,000 mPa · s, more preferably 1 to 1,000 mPa · s, and still more preferably 1 to 100 mPa · s.

  Such hydroxypropyl cellulose can be obtained commercially, for example, Crucelle (KLUCEL: trademark, hereafter the same) LF, Crucell EF, Crucell GF, Crucell JF (all of which are trade names) manufactured by Hercules Co., Ltd. Can be used.

  Among them, it is preferable to use hydroxypropyl cellulose having a low viscosity when improving the loosening of rice grains. Specifically, it is preferable to use hydroxypropylcellulose having a viscosity at room temperature (25 ° C.) of 30 mPa · s or less, more preferably 15 mPa · s or less when prepared in a 2% by weight aqueous solution (measurement conditions; BL type rotational viscometer, rotor No. 1 to 4, rotation speed 6 rpm, 25 ° C.).

  Moreover, when expecting the glossiness and provision | providing effect to rice, it is preferable to similarly use a hydroxypropyl cellulose with low viscosity. Specifically, it is preferable to use hydroxypropyl cellulose having a viscosity at room temperature (25 ° C.) of 15 mPa · s or less, more preferably 10 mPa · s or less when prepared into a 2% by weight aqueous solution (measurement conditions; BL type rotational viscometer, rotor No. 1 to 4, rotation speed 6 rpm, 25 ° C.).

  In particular, when anti-burning effect is expected, it is preferable to use hydroxypropyl cellulose having a low viscosity. Specifically, it is preferable to use hydroxypropyl cellulose having a viscosity at room temperature (25 ° C.) of 15 mPa · s or less, more preferably 10 mPa · s or less when prepared into a 2% by weight aqueous solution (measurement conditions; BL type rotational viscometer, rotor No. 1 to 4, rotation speed 6 rpm, 25 ° C.).

  In particular, when a texture improving effect (a texture deterioration suppressing effect) is expected, it is preferable to use hydroxypropyl cellulose having a low viscosity. Specifically, it is preferable to use hydroxypropylcellulose having a viscosity at room temperature (25 ° C.) of 30 mPa · s or less, more preferably 15 mPa · s or less when prepared in a 2% by weight aqueous solution (measurement conditions; BL type rotational viscometer, rotor No. 1 to 4, rotation speed 6 rpm, 25 ° C.).

  The rice quality improving agent of the present invention only needs to contain hydroxypropyl cellulose, and as long as it contains hydroxypropyl cellulose, it may contain only hydroxypropyl cellulose or may contain other components. As other components, for example, (1) when the rice quality improver of the present invention is used mainly for a loosening effect, water-soluble cellulose ethers other than hydroxypropylcellulose (methylcellulose, hydroxymethylpropylcellulose are preferred as other components ) And the like. In addition, (2) when the rice quality improver of the present invention is used mainly for the glossing effect, other components include water-soluble cellulose ethers other than pullulan and hydroxypropylcellulose (preferably methylcellulose and hydroxymethylpropylcellulose). it can. In the case of containing such other components, the content of hydroxypropylcellulose contained in 100% by weight of the rice quality improving agent is 99 to 10% by weight, preferably 99 in any of the cases (1) and (2). -50% by weight, more preferably 99-90% by weight.

  In addition, when using hydroxypropylcellulose as a rice quality improver, advantages other than the above effects include a low-calorie rice with no oil floating compared to the case where oil is added to improve the loosening and gloss. Can be mentioned. Moreover, the point that it is allergen-free compared with the case where the water-soluble hemicellulose derived from beans is used together can also be mentioned.

  The method for applying the rice quality improving agent of the present invention to rice is not particularly limited as long as the improving agent is finally blended into rice. Preferably, there can be mentioned a method in which the improver is blended with the raw material of the rice and heat-treated together, and a method in which the heat-treated cereal (preferably cooked rice) is treated with the improver.

Specifically, the following methods can be exemplified.
1. A rice quality improver is added to raw cereals (preferably rice) that has been washed in advance to adjust the water, and if necessary, other raw materials are blended and subjected to heat treatment such as rice cooking or steaming.
2. The heat-treated cereal (preferably cooked cooked rice) is surface-treated with a rice quality improver or a solution in which a rice quality improver is dissolved or dispersed in water.
3. A rice quality improver is dissolved or dispersed in a seasoning solution in advance, and this is added to heat-treated rice (preferably cooked rice) to perform seasoning and surface treatment at the same time.
4). The heat-treated cereal (preferably cooked cooked rice) is cooked using oil in which a rice quality improver is dissolved or dispersed.

  Thus, improving the looseness and looseness of the rice grains (especially improving the looseness when the rice is cold), adding gloss to the rice grains (especially when the rice is cold) Is possible. The “surface treatment” referred to in the above 2 and 3 includes, but is not limited to, application (coating), dipping, and spraying treatment.

  Among the above-described treatment methods, methods 2 to 4 are examples of a method of attaching the rice quality improving agent of the present invention to the surface of the rice grain, and are particularly effective for improving loosening and gloss. According to the method 1, the rice quality improver can be penetrated into the inside of the rice best, and in addition to the loosening improvement effect and the gloss imparting effect, the rice is prevented from becoming a harsh texture over time. It is effective to maintain. For this reason, the rice quality improving agent of the present invention can also be used as a texture improving agent (texture deterioration inhibitor) used to suppress deterioration of the texture (elasticity) of cooked rice over time. it can.

  The amount of the rice quality improving agent of the present invention added to the rice varies depending on the type of rice to be applied and its production method (including the processing method), and can be appropriately adjusted accordingly. For example, when a rice quality improver is blended in a rice raw material and heat-treated together to prepare rice (in the case of method 1 above), the ratio of hydroxypropyl cellulose to 100 parts by weight of raw cereal is 0.001 About 5 parts by weight, preferably 0.05 to 3 parts by weight, and more preferably 0.1 to 2 parts by weight can be added.

  Moreover, when preparing rice by surface-treating heat-treated cereals using a rice quality improver (in the case of the above methods 2 to 4), the concentration of hydroxypropylcellulose in the treatment liquid is 0.1 to 5% by weight. The rice quality improving agent can be preferably used so as to be 0.5 to 2% by weight.

(2) Rice quality improving agent containing hydroxypropylcellulose and water-soluble hemicellulose The rice quality improving agent of the present invention may contain water-soluble hemicellulose in addition to hydroxypropylcellulose. When hydroxypropylcellulose and water-soluble hemicellulose are used in combination, the mixing ratio (weight ratio) of hydroxypropylcellulose: water-soluble hemicellulose = 1: 10 to 10: 1, preferably 1: 9 to A 9: 1 ratio can be mentioned. When these are converted into the ratio of water-soluble hemicellulose to 100 parts by weight of hydroxypropylcellulose, it is 10 to 1000 parts by weight, preferably about 10 to 900 parts by weight. The ratio of the water-soluble hemicellulose is more preferably 20 to 250 parts by weight, still more preferably 100 to 200 parts by weight.

  According to such a rice quality improving agent, the above-mentioned rice quality improving effect of hydroxypropyl cellulose (rice grain loosening improvement effect, rice grain glossing effect, non-sticking effect, texture improvement effect (texture deterioration suppression effect)) This can be further improved. Among them, by using a combination of water-soluble hemicellulose and hydroxypropylcellulose, it is possible to exert a good loosening improvement effect not only when warm, but also when the rice is cold or frozen.

  The water-soluble hemicellulose used in the present invention is made from oil seeds (soybeans, palm, coconut, corn, cottonseed, etc.) or cereals (rice, wheat, etc.) and beans (red beans, peas, soybeans, etc.). From cereals or rice cakes from which fats, proteins and starches have been removed in the usual manner, under acidic or alkaline conditions, preferably at a pH near the isoelectric point of each protein, preferably 80 ° C. or higher and 130 The water-soluble fraction is fractionated by thermal decomposition at 100 ° C. or lower, more preferably 100 ° C. or higher and 130 ° C. or lower, and then dried as it is, or further, for example, activated carbon treatment, resin adsorption treatment or ethanol precipitation treatment to make it hydrophobic It can be obtained by removing the substance or low-molecular substance and drying.

  For example, when soybean is used as a raw material, okara produced as a by-product when producing tofu, soy milk, and separated soybean protein can be used as cereal or rice cake excluding the fat, protein and starch.

  The water-soluble hemicellulose thus obtained has an average molecular weight of tens of thousands to several millions, and approximately 80% or more of its composition is a polysaccharide, and additionally contains crude ash, crude protein and water. In addition, galactose is the most constituent sugar, followed by uronic acid and arabinose, other xylose, fucose, rhamnose and glucose.

  Examples of the raw material for the water-soluble hemicellulose used in the present invention include those described above, but from the viewpoint of solubility and industrial properties, those derived from beans, particularly soybeans, especially those derived from cotyledons are preferred. This water-soluble hemicellulose can be obtained commercially, and examples thereof include SM-700 and SM-1200 (both trade names) manufactured by San-Ei Gen FFI Co., Ltd.

  The rice quality improving agent of the present invention comprises hydroxypropyl cellulose and water-soluble hemicellulose in a ratio of 1:10 to 10: 1 (weight ratio) (water-soluble hemicellulose 10 to 1000 parts by weight with respect to 100 parts by weight of hydroxypropylcellulose), preferably May be contained at a ratio of 1: 9 to 9: 1 (weight ratio) (about 10 to 900 parts by weight of water-soluble hemicellulose with respect to 100 parts by weight of hydroxypropylcellulose). It may be composed of two components of crystalline hemicellulose, or may contain other components. As other components, for example, (1) when the rice quality improver of the present invention is used mainly for a loosening effect, water-soluble cellulose ethers other than hydroxypropylcellulose (methylcellulose, hydroxymethylpropylcellulose are preferred as other components ) And the like. In addition, (2) when the rice quality improver of the present invention is used mainly for the glossing effect, other components include water-soluble cellulose ethers other than pullulan and hydroxypropylcellulose (preferably methylcellulose and hydroxymethylpropylcellulose). it can. In the case of containing such other components, the content of hydroxypropylcellulose contained in 100% by weight of the rice quality improving agent is 5 to 90% by weight, preferably 5 in any of the cases (1) and (2). The weight percent may be at least 90% by weight. More preferably, it is 25 to 70% by weight, and further preferably 25% by weight or more and less than 50% by weight.

  The method of applying the rice quality improver of the present invention to rice is not particularly limited as long as the improver is finally blended into rice, and as described above, the improver is used as a raw material for rice. The method of mix | blending and heat-processing together (for example, said 1 method) and the method of processing heat-processed grain using the said improving agent can be mentioned (for example, the method of said 2-4).

  The amount of the rice quality improving agent of the present invention added to rice varies depending on the type of rice and its preparation method (including processing method), and can be appropriately prepared accordingly. When blended with raw materials and heat-treated together (in the case of method 1 above), the ratio of the total amount of hydroxypropyl cellulose and water-soluble hemicellulose to 100 parts by weight of raw cereal is about 0.001 to 2 parts by weight, preferably It can be added at a ratio of 0.01 to 1 part by weight, more preferably 0.1 to 1 part by weight.

  Moreover, when processing heat-processed cereal using a rice quality improving agent and manufacturing rice (in the case of the said method of 2-4), the density | concentration of the total amount of the hydroxypropyl cellulose and water-soluble hemicellulose in a process liquid is 0. A rice quality improving agent can be used so that it may become 1 to 5 weight%, Preferably it is 0.5 to 2 weight%.

(3) Rice prepared using rice quality improver and method for producing the same The present invention also provides rice prepared using the rice quality improvers of (1) and (2) above. Such rice can be produced by blending the above rice quality improver into a rice raw material and heat-treating it together, or by treating heat-treated cereal with the improver.

Specifically, the following methods can be exemplified.
1. A rice quality improver is added to raw cereals (preferably rice) that has been washed in advance to adjust the water, and if necessary, other raw materials are blended and subjected to heat treatment such as rice cooking or steaming.
2. The heat-treated cereal (preferably cooked cooked rice) is surface-treated with a rice quality improver or a solution in which a rice quality improver is dissolved or dispersed in water.
3. A rice quality improver is previously dissolved or dispersed in a seasoning liquid, and this is added to heat-treated cereals (preferably cooked rice), and seasoning and surface treatment are simultaneously performed.
4). The heat-treated cereal (preferably cooked cooked rice) is cooked using oil in which a rice quality improver is dissolved or dispersed.

  Other than this operation, it can be prepared according to conventional methods depending on the type of rice. In addition, about the application quantity of a rice quality improvement agent, it is as having demonstrated in (1) and (2).

  The rice of the present invention thus prepared is improved in the loosening of the rice grains, particularly in the cold state or in the frozen state, and further has a mottle in the cold state. In addition, there is no manufacturing loss because the burn-in is prevented by blending the rice quality improver. Furthermore, in particular, the rice of the present invention prepared by the method 1 has moderate elasticity even when it is cold, in addition to the loosening-improving effect and the gloss-imparting effect. I have.

  Therefore, the present invention also provides a method for producing rice with improved loosening (especially rice with improved loosening when cold). Such a method can be said to be a method for improving the loosening of rice from another angle. Moreover, this invention also provides the method of manufacturing the rice which has luster (especially rice which has luster when it is cold). Such a method can also be said to be a method of polishing the rice from another angle. Furthermore, the present invention also provides a method for producing rice that is difficult to burn. Such a method can be said to be a method of suppressing the burning of rice from another angle. Furthermore, this invention also provides the method of manufacturing the rice (texture deterioration suppression rice) by which the temporal deterioration of the texture (elasticity) was suppressed. From another angle, this method can also be referred to as a method for suppressing deterioration of the texture of rice or a method for maintaining the elasticity of rice.

  The rice of the present invention is characterized by being prepared using the above-mentioned rice quality improving agent. However, as long as the effect of the present invention is not adversely affected, other thickening stabilizers such as xanthan gum, guar gum, Tamarind seed gum, locust bean gum, carrageenan, pectin, glucomannan, alginic acid, sodium alginate, curdlan, gum arabic, karaya gum, gati gum, psyllium seed gum, gellan gum, tara gum, pullulan, pectin, ramzan gum, hydroxypropylcellulose It can also be prepared using a polysaccharide-based thickening stabilizer such as water-soluble cellulose ether (such as methylcellulose or hydroxymethylpropylcellulose). Further, it can be prepared by using a protein-based improving agent such as egg white protein, wheat protein, plasma protein, and whey protein.

  In addition to the above, the rice of the present invention is egg white, egg yolk, chicken egg (whole egg), glycerin fatty acid ester, organic acid monoglyceride, polyglycerin fatty acid ester, polyglycerin condensed ricinoleic acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, Sucrose fatty acid ester, stearoyl calcium lactate, lecithin, enzyme-decomposed lecithin, or enzyme-treated lecithin may be used in combination with an appropriate amount, and is effective for improving the texture.

  In addition, as raw materials used for rice other than the above, for example, livestock meat such as beef, pork and chicken, vegetables such as potato, carrot and onion, butter and milk fat such as cream, lard, pork fat and beef fat Well-known raw materials such as fats and oils such as animal oils and fats, vegetable fats and oils, milk raw materials such as cow's milk, skim milk powder, whole fat powdered milk, whole fat sweetened condensed milk, skimmed sweetened condensed milk and sour cream can be mentioned.

  Hereinafter, the present invention will be described in more detail using experimental examples and examples. However, these examples do not limit the present invention. In the text, “%” means “% by weight”. Moreover, the viscosity described regarding hydroxypropyl cellulose means the viscosity at the time of room temperature (25 degreeC) at the time of preparing to 2 weight% aqueous solution (measuring conditions; BL type rotational viscometer, rotor No. 1-4, rotation speed) 6rpm, 25 ℃).

Experimental Example 1: Rice ball; Evaluation of loosening effect According to the formulation shown in Table 1, water-soluble hemicellulose or / and hydroxypropylcellulose (HPC) was added as a rice quality improver to 20 ° C. water, and stirred and dissolved with a stirrer for 10 minutes. Then, in addition to the well-polished white rice, it was cooked with an electronic rice cooker (SR-MA10 made by National).

  70g of cooked rice is put into a rice ball mold to make rice balls, (1) immediately after cooking, (2) after standing to cool at room temperature, (3) after storing overnight in a 5 ° C refrigerator, and (4) The looseness and the texture when heated and thawed in the microwave oven the next day after freezing were evaluated. The results are shown in Table 2. The loosening was evaluated according to the following criteria.

<Feeling evaluation>
○: Very easy to unravel △;

  As shown in Table 2, the cooked rice prepared using hydroxypropyl cellulose (HPC) (Examples 1 and 2) is easily loosened because the binding between the rice grains is suppressed regardless of whether it is warm or cold. It was. In particular, compared to the cooked rice of the control and the comparative example, the loosening improvement effect in the cold time was remarkable. Cooked rice prepared using only water-soluble hemicellulose (Comparative Example 1) shows a loosening effect when warm, but compared with cooked rice prepared using hydroxypropylcellulose as described above (Examples 1 and 2). The loosening improvement in the cold was significantly lower.

  In addition, with regard to texture (elasticity), cooked rice prepared using hydroxypropylcellulose (HPC) (Examples 1 and 2) has moderate elasticity regardless of whether it is warm or cold. It was. In particular, the elasticity was maintained even when cold compared with the cooked rice for control and comparative examples, and the elasticity was maintained after thawing with a microwave oven as compared with the cooked rice for control.

Experimental Example 2: Cooked rice; Evaluation of gloss effect of appearance According to the formulation shown in Table 3, water-soluble hemicellulose or / and hydroxypropylcellulose (HPC) was added to water at 20 ° C., and stirred and dissolved with a stirrer for 10 minutes. After preparing the rice quality improving agent containing solution, in addition to the white rice well-polished into this solution, it cooked with the electronic rice cooker (SR-MA10 made from National). The cooked cooked rice was frozen to prepare frozen cooked rice. As a control, white rice was cooked in the same manner as above except that no rice quality improver was added.
The glass was thawed the next day, and the appearance gloss (gloss) was evaluated immediately after thawing (warm) and after 2 hours at room temperature (cold). The results are shown in Table 3.

  As shown in Table 3, the cooked rice (Examples 3 to 5) prepared using hydroxypropylcellulose (HPC) showed good gloss both when warm and when cold. In particular, the effect was significantly increased as the amount of hydroxypropylcellulose (HPC) was increased and by using hydroxypropylcellulose (HPC) in combination with water-soluble hemicellulose. On the other hand, cooked rice prepared without using hydroxypropyl cellulose (HPC) (Comparative Examples 2 to 3) is glossy in the same way as normal cooked rice (control) at the time of warmth, but it is not glossy at the time of cold. It was.

Example 6: Preparation of cooked rice In accordance with the formulation shown in Table 4 below, hydroxypropylcellulose (HPC) was added to water prepared at 20 ° C, stirred and dissolved with a stirrer for 10 minutes, and this was polished well. In addition, the ingredients, soy sauce and soup stock were combined and cooked as usual. The obtained cooked rice had good looseness and was able to prevent scorching on the rice cooking kiln. Also, there was little sticking of the rice to the rice cooking kiln, and it was easy to take out the cooked rice from the kettle. Therefore, the cooking rice disposal rate is reduced, and product loss can be kept to a minimum.

  As a control, except that hydroxypropylcellulose (HPC) was not added, cooked rice was prepared in the same manner as in Example 6 above, but there was much scorching to the rice cooking kiln, and there was sticking of rice cooking to the kama In many cases, it was difficult to remove rice from the cooked rice and the loss increased.

Claims (15)

  A rice quality improver comprising hydroxypropylcellulose.   The rice quality improvement according to claim 1, further comprising water-soluble hemicellulose, wherein the ratio of hydroxypropyl cellulose to water-soluble hemicellulose is 1:10 to 10: 1 (weight ratio). Agent.   The rice quality improving agent according to claim 1 or 2, which is a loosening improving agent.   The rice quality improving agent according to claim 1 or 2, which is a gloss imparting agent.   The rice quality improving agent according to claim 1 or 2, which is a non-sticking agent.   The rice quality improving agent according to claim 1 or 2, which is a texture improving agent.   Rice containing the rice quality improving agent according to any one of claims 1 to 6.   A loosening agent for rice is characterized in that the loosening improver according to claim 3 is blended with rice ingredients to prepare rice, or heat-treated cereals are processed using the loosening improver according to claim 3. How to improve.   A method for polishing rice, comprising preparing the rice by blending the luster imparting agent according to claim 4 into a rice raw material, or treating the heat-treated cereal with the luster imparting agent according to claim 4. .   A method for preventing the burning of rice, comprising preparing the rice by blending the non-sticking agent according to claim 5 into a rice raw material, or treating the heat-treated cereal with the non-burning agent according to claim 5. .   A method for suppressing deterioration of the texture of rice over time, comprising preparing the rice by blending the texture improving agent according to claim 6 into a rice raw material.   The loosening improving agent is characterized in that the loosening improving agent according to claim 3 is blended with rice ingredients to prepare rice, or heat-treated cereals are processed using the loosening improving agent according to claim 3. Method of cooked rice.   The luster imparting agent according to claim 4 is blended with rice ingredients to produce rice, or heat-treated cereals are processed using the luster imparting agent according to claim 4. A method for producing rice.   The non-sticking agent according to claim 5 is mixed with a rice raw material to prepare rice, or the heat-treated cereal is treated with the non-sticking agent according to claim 5 to prevent burning. A method for producing rice. A method for producing rice in which deterioration of texture over time is suppressed, wherein the rice texture is prepared by blending the texture improving agent according to claim 6 with rice ingredients.