Method for extracting protein of rice residue

Abstract

The invention belongs to the technical field of food research and development and relates to a research on a method for extracting the protein of rice residue. The method comprises the following steps: soaking 1000g rice residues in a 0.02mol / L NaOH solution for 1-2 hours, grinding the rice residues and filtering by using a 100-mesh sieve; adding 0.09mol / L NaOH solution based on a ratio of sample to solution of 1:(7-9), extracting for 3-4 hours at room temperature, centrifugally separating at 4000r / min, and leaving the liquid supernatant; adding 0.09mol / L NaOH solution into the sediment at the ratio of sample to solution of 1:(3-4), extracting for 1-2 hours at room temperature, centrifugally separating at 4000r / min, and leaving the liquid supernatant; merging the liquid supernatants acquired at two times, adding 0.2mol / L HCL solution till the pH of solution is 4.0-4.5, and centrifugally separating at 4000r / min; drying the sediment in sponging manner; and then packaging the products. By using the method provided by the invention, the rice protein can be continuously extracted from the rice residues in large scale, the protein extracting ratio is high, the rice separated protein of which the protein extracting ratio is 87.46% and the purity is 80.7%, can be acquired, the production cost is low, and the method is fit for industrialized production.

Description

technical field [0001] The invention belongs to the technical field of food research and development. The invention relates to the research on the extraction process of rice dreg protein and is suitable for industrial production. Background technique [0002] The two main components of rice are starch and protein, which are about 80% and 8% respectively. According to their solubility, rice protein can be divided into 4 types: water-soluble albumin, salt-soluble globulin, alkali-soluble glutenin and gliadin. Among them, gluten and globulin are the main components, accounting for 80% and 12% respectively, and gliadin accounts for 3%. The value of rice protein is mainly reflected in its hypoallergenic, non-pigmentation interference, soft and non-irritating taste and its high nutritional value. It is rich in essential amino acids for the human body, especially lysine content is higher than other grains. The biological value of rice protein is as high as 77, ranking first amo...

AI Technical Summary

Problems solved by technology

However, the efficiency of enzymatic extraction of rice protein is lower than that of the alkaline method, and the resulting product is soluble in water, and the protein cannot be recovered by the isoelectric point method, so the yield is very low, and the residual protein in the starch is also more than that extracted by the alkaline method.

At present, the process conditions of enzymatic extraction are not mature, and there are relatively high requirements for enzyme activity, high cost, low protein purity of the product obtained, and darker color of the product.