Study On Debittering Peptide Preparation From De-suger Rice Residue

Rice protein, a kind of high-quality plant protein, is equilibrium in the amino acid composition which matches reasonable with each other. With higher biological value and digestibility as well as lower allergic, it is suitable for infants and special groups, so it is respected to be wide prospect of market. In this paper, based on sugar rice dregs as raw material, a new process was claimed to prepare rice protein, the technological process design and preliminary cost accounting were also carried out.The technology process was initially definition as follows after analyzing the issue : rice dregs—de-esterification—deglycosylation—enzymolysis—characterization. Acid protease, alkali protease and neutral protease were used to choose the proper enzyme, and the neutral protease was found to be the best for enzymolysis. The enzymolysised products of several neutral protease were compared with protein content, yield and hydrolysis degree as index, and the comprehensive index for the trypsin products was better.By single factor experiments, the best enzymatic hydrolysis process for trypsin was determined: added enzyme quantity (E/S) for 0.2%, pH for 7.4, time for 12h, temperature for 45℃during the enzymolysis process.According to the cause analysis of protein products bitterness as well as the comparison of the debittering method, the idea of debittering by exonuclease was proposed. By adopting trypsin as the main cutting enzymes and high-efficiency protease as the coenzyme in the test, the protein content of the enzymolysis product was slightly improved, and the hydrolysis degree was about three times as much as trypsin used only, meanwhile the bitter was removed. Comprehensive product yields and hydrolysis degree of two indexes, the optimal process for rice protein by double enzymes hydrolysis was put forward: solid-to-water ratio was 1:6, trypsin dosage was0.2%, high-efficiency protease dosage was 0.1%, high-efficiency protease was added 4h later than trypsin.It was shown that the craft for rice protein production by double enzymes hydrolysis was easy and reasonable, with no wastewater discharged, of less environmental pollution. The product was proved to be with great production benefits because of good water-solubility and easily being digested and absorbed by human body, and the reasonable amino acid composition. This new technology should have a prosper market potential.