JP2007195446A - Functional agent for food, comprising water-soluble polysaccharide derived from of rice bran - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide water-soluble polysaccharide efficiently extracted so as to effectively use rice bran and usable as a functional material improving food physical properties and function in addition to function as dietary fiber. <P>SOLUTION: The water-soluble polysaccharide which is obtained by treating rice bran in high temperature and strong alkali conditions functions as a sticking preventing agent of cereal food such as noodles and boiled rice, an emulsifier and a food coating agent in addition to function as dietary fiber. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a water-soluble polysaccharide derived from rice bran, and in particular, obtained from extraction from rice bran under alkaline conditions, an emulsion stabilizing function, a function for preventing binding of noodles and cereals, and a rice bran water-soluble polysaccharide excellent in coating properties About the usage of.

  Currently in Japan, 1 million tons of rice bran is discharged during the milling process. About 40% of rice bran is used as a raw material for oil extraction, but the defatted rice bran produced in the process has been incinerated as industrial waste without being effectively utilized so far.

  In addition, there are reports of rice bran polysaccharides extracted from rice bran alkali, but these are mainly used for dietary fiber reinforcement (dietary fiber), and can be added without affecting the flavor of food. Has been studied. [Patent Document 1] reinforces dietary fiber by adding it to foods such as juice, cookies, and bread. In [Patent Document 2], it is used as a colorectal cancer inhibitor as a physiological function of dietary fiber. However, no functionality that improves the physical properties and functions of foods has been found.

Japanese Patent Publication No.6-11764 Japanese Patent Laid-Open No. 5-112455

  In order to make effective use of rice bran, in addition to its function as a dietary fiber, it was used as a functional material to improve the physical properties and functions of foods and to extract water-soluble polysaccharides more efficiently.

  As a result of earnest research to solve the above problems, the water-soluble polysaccharide of the present invention has a function as a dietary fiber, for example, without further hydrolysis treatment with an enzyme, for example, cereal foods such as noodles and cooked rice It became clear that it functions as an anti-binding agent, emulsion stabilizer, and food coating agent. Furthermore, it came to the knowledge which can extract the functional polysaccharide which is a cell wall structural component efficiently by processing rice bran under high-temperature conditions and strong alkali conditions. The present invention has been completed based on such findings.

That is, the present invention
(1) A food function agent comprising a water-soluble polysaccharide extracted from rice bran under alkaline conditions.
(2) The food function agent according to (1), wherein the alkaline condition is pH 12 or more.
(3) The food function agent according to (1), which is used for preventing cereal food binding.
(4) The food function agent according to (1), which is for emulsification.
(5) The food function agent according to (1), which is for coating.
(6) A food comprising one or more selected from the functional agents according to (3) to (5).
(7) A method for producing a water-soluble polysaccharide, wherein a water-soluble fraction is extracted from rice bran by an alkaline condition and a treatment at 95 ° C or higher.
It is.

  The water-soluble polysaccharide extracted from rice bran under alkaline conditions has a function of preventing the binding of cereal foods and improving the fogging property, and also has emulsion stability and film property. Moreover, the foodstuff excellent in the said function was able to be obtained by using the water-soluble polysaccharide of this invention. Furthermore, water-soluble polysaccharides could be extracted efficiently by extracting at high temperature under alkaline conditions.

  The rice bran used in the present invention refers to all rice bran produced as a by-product when rice is polished, and includes defatted rice bran and the like. Rice bran contains a large amount of fats and oils rich in unsaturated fatty acids, and becomes a peroxide and easily causes a problem in flavor. Therefore, defatted rice bran obtained by defatting lipids with hexane or the like in advance is preferred as a raw material.

  Any of the water-soluble polysaccharides extracted from rice bran under alkaline conditions can be used as an anti-binding agent, an emulsion stabilizer, and a coating agent for cereal foods. The method for producing rice bran polysaccharide will be described in detail as follows. Extraction of rice bran as it is or after pulverization is performed under alkaline conditions, but the yield tends to be slightly lower at pH 11 or lower, so pH 12 or higher is preferable, and a pH of 14 or higher requires a large amount of alkali. The property is low, and a pH of 13 or less is more preferable. The extraction time is not particularly limited, but is preferably about 2 minutes to 2 hours. The temperature condition is not particularly limited and can be carried out at room temperature or higher, but the total sugar amount of the extracted polysaccharide, that is, the polysaccharide purity is high, preferably 95 ° C. or higher, more preferably 135 ° C. or lower. Most preferred is a temperature of 105 ° C. or higher and 130 ° C. or lower, which has a high total sugar amount and high water solubility. Heating exceeding 100 ° C. is performed under pressure in a pressurized container or the like.

  There are no particular restrictions on the alkali used to adjust the pH during extraction, and any alkali can be used. However, alkalis such as sodium hydroxide, potassium hydroxide, calcium hydroxide, and ammonia can be used to achieve alkaline conditions. I can do it. The pH of the obtained extract is arbitrarily adjusted, and the water-soluble fraction is separated by centrifugation or the like. In adjusting the pH, inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid, or organic acids such as acetic acid, citric acid, lactic acid and oxalic acid can be used. The polysaccharide thus obtained can be dried and used as it is, but it is preferable to carry out further purification in order to remove mixed impurities.

  Examples of the desalting and purification treatment include precipitation using a polar organic solvent such as methanol, ethanol, isopropanol, and acetone, electrodialysis, ion exchange resin or hydrophobic resin, and membrane fractionation using a UF membrane. . One of these methods or two or more methods can be used in combination. Among them, the precipitation method using a polar organic solvent is efficient and preferable, and the use of ethanol is particularly preferable. The purified rice bran polysaccharide solution is dried by freeze drying, spray drying or the like to obtain a powdered rice bran polysaccharide.

  The viscosity of the polysaccharide solution obtained in the present invention is not particularly limited, but it exhibits a viscosity of 200 cP · s, preferably 100 cP · s or less at 20 ° C. in a 5 wt% solution. As a result of analyzing the constituent sugars of the rice bran water-soluble polysaccharide by the method described in JP-A-11-049682, glucose, arabinose and xylose are used as constituent sugars. All the obtained polysaccharides have a molecular weight of 1 million or less, preferably 500,000 or less, as analyzed by gel filtration HPLC (TSKgel-G-5000 PWXL; TOHSO). The average molecular weight of this polysaccharide is a value measured using a standard substance pullulan (Showa Denko KK) as a standard substance.

  The water-soluble polysaccharide of the present invention can be used as an anti-binding agent for cereal foods, that is, noodles or cooked rice, alone or in combination with other quality improvers and additives. Other quality improvers and additives include emulsifiers such as lecithin, glycerol fatty acid esters and sucrose fatty acid esters, or other fats and oils such as general animal and vegetable oils and fat-soluble vitamins such as tocopherol, sucrose, maltose, trehalose, etc. Carbohydrate and sugar alcohol, dextrin, cloth nori, agar, carrageenan, fercelan, tamarind seed polysaccharide, tara gum, caraya gum, pectin, soy hemicellulose, xanthan gum, sodium alginate, gum arabic, hyaluronic acid, cyclodextrin, chitosan, carboxymethylcellulose, alginic acid Polysaccharides such as various starches such as propylene glycol ester and modified starch, hydrolysates of these polysaccharides, albumins such as gelatin and whey, sodium caseinate, soluble collagen, egg white, egg yolk And proteinaceous substances such as soybean protein, salts such as calcium fortified, pH adjusting agents such as sodium acetate and the like. Therefore, the binding inhibitor for cereal food according to the present invention is not only in a powder state but also in an emulsified state or a suspended state with fats and oils, or in a state of a solution added to an organic acid solution such as water, saline or acetic acid. Can be used.

  The amount of addition when the water-soluble polysaccharide of the present invention is used as an anti-binding agent is not particularly limited, but for example, 0.2% to 10% by weight, preferably 0.5% for noodles or cooked rice. It is preferably used in the range of 5 to 5% by weight. There is no particular restriction on the timing of adding the water-soluble polysaccharide, and when adding to noodles, it is added in advance to boiling water or hot water, or surface treatment is performed by entanglement of boiled noodles with aqueous solution. The noodles can be surface treated by spraying an aqueous solution. In addition, when manufacturing noodles, powders or solutions can be added to make noodles. When added to cooked rice, it can be added to cooked rice in advance and cooked. However, it is preferable to surface-treat the cooked rice or steamed cooked rice with an aqueous solution, or spray the aqueous solution to perform surface treatment. Further, in the case of fried rice such as fried rice, powder can be added or an aqueous solution can be added before or during the frying process.

  The grain foods targeted by the present invention are noodles such as udon, soba noodles, raw noodles, cold wheat, Chinese noodles, pasta, rice noodles, etc., which can be used for both dry and raw noodles including instant noodles. it can. Examples of cooked rice include white rice, salted rice, red rice, barley rice, butter rice, pilaf, yakimeshi, baked rice, and fried rice.

  When the water-soluble polysaccharide of the present invention is used as an emulsifier, it is possible to make an emulsion at any pH range, but it is preferable to make an emulsion at pH 4 to pH 9, and a neutral pH range of pH 6 to pH 8 More preferred. The addition amount is not particularly limited, but the addition amount in the emulsion is 0.05 to 25% by weight, preferably 0.1 to 15% by weight, and the emulsion has an oil content of 5 to 50% by weight. Can be made. The addition timing of the water-soluble polysaccharide is not particularly limited, but an emulsion can be obtained by dissolving in advance in the aqueous phase or dispersing in the oil phase.

  The water-soluble polysaccharide of the present invention can be used as a coating agent, and a film can be prepared by making glycerin or the like into a solution using a plasticizer and drying it. Although a film can be formed even in a solution containing no plasticizer, it is desirable to add a plasticizer such as glycerin in order to improve the plasticity of the film. The polysaccharide concentration of the solution is not particularly limited, but is desirably 1% to 30% by weight, preferably 5% to 20% by weight. The rice bran-derived film thus obtained can be used as an edible film. The edible film may be used alone, or may be used for a packaged food obtained by packaging food with an edible film, such as candy and caramel. The use of the edible film of the present invention is not limited to edible use. For example, the edible film can be used for coating non-edible products such as cosmetics, agricultural chemicals and seedlings.

  The film agent comprising the present water-soluble polysaccharide also functions as a coating agent that prevents quality deterioration due to drying and fading of frozen foods. In particular, frozen foods have a poor taste due to drying of the surface upon thawing and generation of drip, and overcooking when reheated, causing a burnt color or a burnt odor to adhere to the food. By subjecting the present water-soluble polysaccharide aqueous solution to a surface treatment, it is possible not only to prevent quality deterioration of various foods including frozen foods, but also to gloss the food surface. The concentration of the polysaccharide aqueous solution used for the surface treatment is not particularly limited, but it is desirably 0.5% to 15% by weight, preferably 1% to 10% by weight.

  Hereinafter, the present invention will be described by way of examples, but these are examples and the contents of the present invention are not limited by these examples. In the examples, “%” means a weight basis unless otherwise specified.

  150 g of commercially available defatted rice bran was added to 3 kg and adjusted to pH 9, 11, 13 using sodium hydroxide. These were heated under pressure at 110 ° C. for 90 minutes to extract water-soluble polysaccharides. After adjusting the pH to 7, the obtained slurry was centrifuged (8000 G × 30 minutes, room temperature), and ethanol was added to the supernatant to a concentration of 60%. The precipitate was collected by centrifugation (8000 G × 30 minutes, room temperature) and lyophilized. The analytical values of the obtained polysaccharide are shown in Table 1. As a composition analysis method for these polysaccharides, the total sugar was quantified using the phenol-sulfuric acid method, the starch was quantified by the iodine starch method, the reducing sugar was quantified by the Sommoji Nelson method, the uronic acid was quantified by the Blumenkrantz method, and the crude protein was quantified by the Kjeldahl method. The water-solubilization rate is the ratio of the solid content that has been water-solubilized after heat extraction with respect to the solid content of the raw material, and the eta precipitation yield is the ratio of the solid content of ethanol precipitation to the solid content of the raw material. It is a value expressed in%.

[Table 1] Composition analysis values at each pH at 110 ° C extraction

  When the pH was 11 or less, the water solubility was as low as 40% or less, and the total amount of sugar was also small. In addition, since the protein content increased in the extraction of the weak ant potash region of pH 9 to 11, it was judged that the pH suitable for extraction is preferably 12 or more.

  150 g of commercially available defatted rice bran was added to 3 kg and adjusted to pH 13 using sodium hydroxide. These were heated at a temperature of 60 ° C. to 135 ° C. for 90 minutes to extract water-soluble polysaccharides. After adjusting the pH to 7, the obtained slurry was centrifuged (8000 G × 30 minutes, room temperature), and ethanol was added to the supernatant to a concentration of 60%. The precipitate was collected by centrifugation (8000 G × 30 minutes, room temperature) and lyophilized. The analytical values of the obtained polysaccharide are shown in Table 2.

[Table 2] Composition analysis values at each temperature during pH13 extraction

  In the extraction at 100 ° C. or higher, the total sugar amount, that is, the polysaccharide purity exceeded 60%, and water-soluble sugar was efficiently extracted. Although the total sugar amount tended to decrease from around 130 ° C, the total sugar amount and the water-solubilization rate were high at 135 ° C, which was considered acceptable. From the above, the extraction temperature is preferably 95 ° C. or higher, and more preferably 135 ° C. or lower. Of the polysaccharides prepared under the conditions of Example 2, a pH 3,110 ° C. extracted polysaccharide with the highest total sugar amount was used as rice bran polysaccharide A in the following examples.

Preparation of anti-binding agent for noodles Frozen udon (manufactured by Katoyoshi Co., Ltd.) was boiled with boiling water for 1 minute, thawed with running water, drained with a sieve, and then divided into 100 g turtle shell containers. Add 5 g of rice bran polysaccharide A aqueous solution of 0.2% to 1.0% as the control group, mix well and allow the polysaccharide aqueous solution to adhere uniformly to the noodles, then store at 4 ° C overnight. did. For comparison, soybean hemicellulose (Soya Five-S-LA200 manufactured by Fuji Oil Co., Ltd.) was used. After storage, the noodles were lifted with chopsticks and observed for hoggle condition. In addition, the texture of the noodles was evaluated by a sensory test. In this case, “haggling” means that when two noodles are lifted with chopsticks, the lifted noodles can be unwound without breaking.

[Table 3] Anti-binding effect of noodles

  As a result, in the additive-free zone, the whole noodles adhered to the container and became a lump. On the other hand, in the rice bran polysaccharide A-added section, the use of a concentration of 0.5% or more showed fogging.

Addition to fried rice 480 g of water was added to 320 g of raw rice and cooked. After 500 g of rice and 12.5 g of salad oil were fried together, 2.2 g of rice bran polysaccharide A was added, and the degree of hoggle was evaluated visually and by a sensory test. As a result, the rice bran polysaccharide A-added group showed better hogability of rice than the non-added group.

○ Evaluation of emulsion stability After adding an oil phase to the aqueous phase with the following composition, an emulsion was prepared by ultrasonic treatment (5281 type vibrator; KAIJO DENKI), and stored at 4 ° C. In Table 4, “%” is volume%.

[Table 4] Emulsion blend

  The particle size of these emulsions was measured over time using a laser particle size distribution analyzer (SALD-2000; Shimadzu Corporation). Table 5 shows the average emulsified particle size after 0, 1, 7 days.

[Table 5] Change in particle diameter of each emulsion

  As a result of the above, the emulsion using rice bran polysaccharide A as an emulsifier did not separate oil and maintained a stable emulsified state even after storage for one week. In particular, it maintained a stable emulsified state with a small particle size under acidic conditions, and had a very strong emulsifying power.

○ Examination of film properties A film was prepared using rice bran polysaccharide A. The OHP polyester sheet was bonded to the glass plate while flowing the paraffin solution so that air did not enter. An OHP sheet was attached with vinyl tape to produce a frame with an appropriate thickness. A solution was prepared with the following formulation and completely dissolved. Centrifugal degassing was performed at 3,000 rpm for 10 minutes, and the solution was poured into the frame at a uniform thickness. It was dried at 60 ° C. for 1 hour, allowed to cool, and peeled off from the polyester sheet. As a result, the water-soluble polysaccharide formed a film rich in plasticity.

[Table 6] Film formulation

○ Functional evaluation as a coating agent The function of rice bran polysaccharide as a grace agent was evaluated. After the bamboo leaves were washed with water, the water on the surface was removed. The leaf surface was divided into two sections with the central vein as the boundary, and one surface was treated with water and the other was treated with a 5% aqueous solution of rice bran polysaccharide A. Similarly, water or rice bran polysaccharide A aqueous solution was surface-treated on the surface of horse mackerel. The leaves and horse mackerel were stored frozen in contact with the air, and the state after 10 days was observed. As a result, discoloration was recognized by drying in the untreated portion, whereas drying was prevented in the portion treated with rice bran polysaccharide A and the glossy good state was maintained.

  Since it becomes possible to efficiently extract water-soluble polysaccharides from rice bran and defatted rice bran that were originally treated as industrial waste, it is possible to reduce the burden on the environment. In addition, by using the obtained polysaccharide as an anti-binding agent, an emulsion stabilizer, and a coating agent for cereal foods, it has become possible to produce naturally-derived safe foods.

Claims (7)

A food function agent comprising a water-soluble polysaccharide extracted from rice bran under alkaline conditions. The food function agent according to claim 1, wherein the alkaline condition is pH 12 or more. The food function agent according to claim 1, which is used for preventing cereal food binding. The food function agent according to claim 1, which is for emulsification. The food function agent according to claim 1, which is used for a film. A food comprising one or more selected from the functional agents according to claim 3. A method for producing a water-soluble polysaccharide, wherein a water-soluble fraction is extracted from rice bran by treatment under alkaline conditions and at 95 ° C or higher.