猪血蛋白的酶法改性、性能鉴定及其应用

2709碱性蛋白质酶用硫酸铵分步盐析,再经超滤、凝胶过滤色谱柱脱盐浓缩后,冷冻干燥制成精制酶。将从猪血中离心分离得到的血球溶血,按照不同水解度(DH)(12%、14%、16%、和18%)进行酶法水解。由脱色后的蛋白质水解物和先前分离得到的血清混合后,经喷雾干燥制成改性蛋白粉。分别测定了不同水解度改性蛋白质的含氮化合物、糖、脂肪、灰分、水分、氨基酸和微量元素。用凝胶过滤色谱测定了多肽分子量分布并测定了改性蛋白质的功能性质,例如:乳化能力、起泡能力、溶解度、白度等;探讨了DH与它们的关系。最后,就添加改性蛋白质对面包质量的影响作了研究。

Enzymatic Modification Characterization and Applications of protein in Pig Blood

2709 basic protease was purified through ammonium sulphate fractionation, ultrafilbatlon and gel filtration and then lyophilized. Hemolysate of red cell separated from porcine blood was hydrolyzed respectively by the partially purified enzyme prearatioa at the hydrolytic degrees of 12%,14%,16% and 18%. The decoloured hydrolyzates were combined separately with blood serum, and then dried by spray drying. Total nitrogen containing substances, carbohydrates, lipids, ash, moisture, amino acids and trace elements in the modified proteins with diiferent degrees of hydrolysis were assayed. The distribution of molecular weight of polypeptides in the modified proteins was determined by gelfiltration chromatography. The functional properties of the modified protein, such as solubility emulsifying and foaming capacity and whiteness were investigated. The relationship between the functional properties of the modified protein and the degree of hydrolysis were discussed. Finally, the effect of adding modified protein to the improvewent of quality of bread was studied.