A kind of preparation method of edible rice protein

Abstract

The invention relates to a preparation method of edible rice protein. The method comprises the following steps of pre-treating raw materials, crushing, mixing, reacting, separating and washing, drying and the like. According to the method provided by the invention, macromolecular dextrin in rice dreg is washed by using hot water before being aged; impurities in the rice dreg can be separated from protein which is not dissolved in water by crushing and a salt forming reaction of fat; then a cyclone is used for separating and washing so that the separating and washing efficiency is greatly improved; compared with flash drying and spray drying, the preparation method has the advantages that the equipment investment is saved by about 40% and the operation cost is saved by about 35%; the edible rice protein with the protein dry basis content more than 90%, fat content less than 2% and ash content less than 2% is obtained; the extraction rate of the rice protein is more than 85%; the obtained product can be widely applied in food industries, particularly infant foods; compared with a manner of using the raw material rice dreg as a feed, the preparation method has the advantage that the added value of products is greatly increased.

Description

【Technical field】 [0001] The invention belongs to the technical field of rice deep processing. More specifically, the present invention relates to a preparation method of edible rice protein. 【Background technique】 [0002] Rice protein has excellent nutritional quality, the amino acid score is as high as 67, the digestibility is 82, the biological value is 77, and the efficacy ratio is 1.7. Its nutritional value is much higher than that of corn, wheat and other vegetable proteins, and comparable to high-quality animal proteins such as eggs and milk. The amino acid composition of rice protein is reasonably balanced, which is very close to the ideal model recommended by WHO / FAO. The food composition table compiled by the Institute of Nutrition and Food Hygiene of the Chinese Academy of Preventive Medicine shows that the methionine content of rice protein is as high as 2.2%, which is unmatched by other plant proteins and even many animal proteins. The content of arginine in...

AI Technical Summary

Problems solved by technology

[0006] More than 80% of rice protein is glutenin with large molecular weight and poor water solubility. The protein molecules are cross-linked and aggregated through disulfide bonds and hydrophobic groups. During the production of starch sugar, due to long-term high temperature, protein Further denaturation and aggregation between molecules and protein molecules, cross-linking structures will also be formed between protein molecules and fat and other molecules, which will greatly reduce the solubility of proteins. The isoelectric point of various proteins is different, so the alkali used to extract proteins is usually Soluble (or protease-soluble) acid precipitation purification process route, low extraction rate, relatively large process loss

In the process of starch sugar production, protein is separated from larger molecular dextrins before saccharification. If the macromolecular dextrins in rice dregs cannot be removed in time, these dextrins will be lost during the subsequent operation and storage of rice dregs. Aging occurs, and amylase has a poor hydrolysis effect on aged starch or dextrin, which makes these dextrins difficult to be removed by enzymolysis and affects the protein content

In the process of starch sugar production, other impurities in rice are also enriched while protein is enriched, and ash and fat are enriched from about 1% to 8% to 10%. It is widely used in infant food For rice protein, the high ash content is unsafe; the fat will be oxidized and spoiled during the high temperature in the sugar making process and the storage process in the drying process, which is not only an unsafe factor, but also affects the quality of rice protein powder. Therefore, corresponding measures must be taken to remove the free ash in the rice dregs as much as possible, that is, fat or fatty acid, but these ash and fat will be wrapped in the protein during the sugar making process and the drying process of the rice dregs In the cross-linked package structure, a large number of impurities are not easy to remove

Therefore, compared with other cereals, the separation of rice protein is relatively difficult. At present, there is no public report on the preparation method of rice protein with a protein content higher than 90% and a protein extraction rate of more than 80%.

[0007] At present, most protein drying methods use spray drying equipment, and its feed concentration generally does not exceed 20%, otherwise the concentration is too high, and the outlet is easy to block, which will greatly increase the processing capacity of the drying equipment, so the equipment investment will increase and the energy consumption will increase. Also increased, and the drying temperature is higher, the drying efficiency is poor

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