The Study Of Using Rice Residues To Produce Rice Peptide

Rice dregs are the draff left behind by the rice serum that are filtered in the sugar factory, msg factory, farina factory and glucose factory which are manufactured on the basis of raw materials of rice. These industrial manufacture processes utilized the starch in the rice, and the protein containing in the rice accumulates in the byproducts rice dregs. Therefore, the protein contents in the rice dregs are very high (about 40%-70%), but most of them are simply used as feeds, which turns out to be a heavy waste of protein resources. This paper mainly investigates the pretreatment for the ingredients, technology about enzymic method of preparing rice peptide, and part of the physical-chemical properties and biological activities in the rice peptide. Moreover, it is based on the rice residue proteins, aims at making full use of the rice peptide protein resources, making some high additional value-adding rice polypeptide, then fulfills the high value use for the rice protein resources and improves the economical profits.The main study results will be listed below:1.The research removes the majority of the sugar and fat through the unique characteristic that rice residues may contain a lot of impurities like sugar, fat and microorganism. And five factors included rinsing time limits, temperature, how many times need to be rinsed and how liquid & solid ratio influence protein content and protein loss ratio are investigated in this paper. An optimum rinsing condition via sole element test can be the one described below: the liquid & solid ratio is 7:1, temperature is 80℃, time limit is 60mins, and two times to be rinsed. Under this type of circumstance, the protein content will be around 77.2%, the protein loss ratio will be about 3.97%.2.The degradation and modification water-soluble small molecule peptide and free amino acids comes from the hydrolysis of rice dregs. Those peptide and amino acids not only avoids damaging the rice dreg's biological function and decreasing the nutritional value, but it also improves the ability to help human body to digest and absorb those nutrition. Therefore, alkalescency and neutral protease are chosen to complex hydrolyze rice residue. It also did the research about how timing, temperatures, pH value, the amount of enzyme and liquid-solid ratio influence the process that alkalescency and neutral protease hydrolyze rice dregs. What is more, it also contains the orthogonal test of alkalescency and neutral protease which is on the basis of the sole element test. Then the best hydrolysis technology condition will be coming out from the orthogonal test:①Firstly, it comes to the requirement of the alkalescency protease. Enzymic volume has to be 6000U/g, temperature has to be 50℃, pH value needs to be 10.5, liquid-solid ratio requires to be 1:15, the degree of hydrolysis needs 12.52%, and it also needs 5 hours to analysis;②As followed, neutral protein enzyme will be demonstrated. The enzymic volume will be 5000U/g, temperature has to be 45℃, pH value has to be 7, liquid-solid ratio will be 1:10, the degree of hydrolysis needs to be 9.03%, and it also requires 3 hours to analysis. The final degree of complex hydrolysis under this two optimum technology conditions will arrive to 15.68%.3.Rice dregs is a combination of low molecular weight peptides after going through alkaline protease and peptide solution which comes from the hydrolysis of neutral protease. Moreover, a great shift happens to the characteristics of the rice dregs after the process like that. The paper separately investigates the solubility of rice peptide, apparent viscosity, molecular weight, amino acid composition, hydroxyl radical and antioxidant activity, the subject of the research is based on the lyophilized power of the rice peptide. The physicochemical property in the rice peptide is significantly improved during the enzymolysis process, its solubility is evidently increased, and internal friction decreases as well; there exists three eluting peak after the sephadex chromatography of samples. Its molecular weight are 1493Da,631Da and 284Da, the corresponding proportion is 51.7%,18.5%,13.3%; it has a plenty types of amino acid containing in rice peptide which is up to 18, and it is very nutritional as well; different dosage of rice peptide has different certain cleaning ability of the hydroxy radical and superoxide anion radical, the cleaning ability will be stronger with the increase of the concentration. (Its cleaning ability will be 87.68% when the concentration rate is 50mg/mL, then its superoxide anion radical cleaning rate will be up to 50.14%)...