Study On The Preparation Of Soybean Peptide By Enzymatic And Fermentation

Soybean peptide is low molecular peptide mixture, the soybean protein was chosen as the raw material, which was obtained through enzymatic hydrolysis or fermentation. It is more superior physical and chemical properties and physiological function than the soybean protein, therefore, it has a broad prospect of application in food, medicine and feed industry.At present, the soybean peptide was usually prepared by enzymatic hydrolysis and fermentation method, but the soybean peptide from enzyme solution produced the bitter taste, taste was poorer, while from fermentation, although the palate has been improved, but the fermentation time was long, difficult to control the cost, so it is detrimental for mass production.The soybean meal was chosen as raw materia in this paper, using the method of fermentation composite enzyme solution, for the preparation soybean peptide. Firstly, used protease hydrolysis soybean protein high efficiency, then vaccination bacillus subtilis to the enzyme solution liquid, further enzyme solution and improve flavor. This topic in the research as follows and got corresponding conclusion.1. Controlled trials to screening protease E from several protease can be efficient hydrolysis of soy protein, flat transparent ring test to screen out the strains of Bacillus subtilis W2, efficient hydrolysis of soybean meal medium, and determined the growth curve of the strain, and determined the strain of inoculant age, which provide a theoretical basis for subsequent trials.2. The single factor experiment explored the impact of various factors in the preparation process conditions on the concentration of soybean peptide, the preparation process of the soybean peptide was optimized through orthogonal test, got the primary and secondary sequence of soybean peptide concentration level of the factors for the enzymatic hydrolysis time> Add the amount of enzyme> vaccination ratio> fermentation time, the best preparation conditions were enzyme dosage8000U/g, the hydrolysis time was5h, inoculum size2%, fermentation time20h, the soybean peptide concentration was45.33mg/mL. And studied the correlation of soybean peptide concentration and enzyme production in the process.3. Soybean peptide solution decolored process was explored in view of the fermented soybean peptide solution darker,. First filtered the activated carbon powder as a decolored agent, on the basis of single factor experiments, the decolorization process conditions were obtained by orthogonal experiment L9(34): activated carbon1%, the pH7.0, decolorization time60min, decolorization temperature50℃.4. In order to ensure that the subject can be applied to a large number of efficient production methods, the spray drying was applied for the drying of soybean peptide solution. Soybean peptide solution after hydrolysis and by enzymatic fermentation of soybean peptide solution were spray drying, Investigated process parameters to determine the spray drying conditions were both:inlet temperature180℃, the ventilation rate100%, the outlet temperature of80-85℃, the feed pump speed8r/min, moisture content in the enzymatic sample and fermented samples were4.52%and5.62%respectively.5. The product indexes was similar to lenon-peptide by analyzing the basic ingredients, molecular weight distribution and amino acid composition of the various samples, which drawn up the requirements, and on this basis, developed the product quality criteria:the total protein content≥50%, soy peptide content≥40%Moisture≤8%, ash≤8%, and sensory requirements section.