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Corn gluten meal is the main byproduct of corn starch production, particularly poor solubility in water, rough texture, lack of lysine, tryptophan, an essential amino acid, a serious impact on its application in the food industry. Zein into the polypeptide of the small molecules by enzymatic method in addition to having the digestible absorbing properties, but also has many good features and physiological activity, and can be widely applied to the field of food. Start from maize yellow pigment extracted from corn gluten meal, quadratic rotary regression test designed to optimize the extraction of maize yellow pigment process. Maize yellow pigment extracted optimal parameters: liquid ratio 5:1, extraction temperature is 60 ℃, the extraction time was 70 min, ultrasonic power 80W, obtained under the conditions of the process validation absorbance to 1.038, and prediction the relative error of the value 1.070 0.747%, indicating that the model is reliable. Extraction of maize yellow pigment after corn protein powder as raw material to extract zein, rotating quadratic regression test designed to optimize the extraction technology of zein, zein extracted optimal parameters: 80% ethanol as a solvent, liquid to solid ratio 14:1, materials fineness 20 mesh, microwave power 420W, microwave treatment zein extraction rate of 25.68%. Zein extracted biphasic (the alcohol phase and a water phase) is subjected to hydrolysis in two steps, the indicator of the degree of hydrolysis and protein conversion rate, obtained by single factor and orthogonal test zein hydrolyzed conditions: 55 ° C, the condition of pH9, plus the amount of enzyme protein in 4% (W / W). Hydrolysis 50 min under this condition, the degree of hydrolysis can be up to about 31.05%, 95.55% protein degradation rate can be achieved. Corn gluten meal as a raw material, using alkaline protease, its hydrolysis to the indicators of the degree of hydrolysis and protein conversion was investigated temperature, amount of enzyme, substrate concentration, pH and hydrolysis time to hydrolysis, on this basis, Orthogonal experiment, to obtain the hydrolysis of corn gluten meal optimum conditions: Substrate concentration is 10%, the amount of the enzyme (E / S) 4%, the hydrolysis time of 3 h, the degree of hydrolysis of 40.39% under this condition, protein degradation rate of 89.83%. Polypeptide corn protein obtained by hydrolysis of the mouse acute toxicity test results show that this peptide is safe. The physiologically active peptide of the corn, a preliminary study, the test results show that corn peptide has a certain resistance to oxidation, but also has strong hangover activity.
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