脱酚棉籽分离蛋白功能特性研究

Functional characteristics of the degossypol cottonseed protein isolate

为拓宽棉籽蛋白在食品领域应用范围,对棉籽分离蛋白基本功能性质进行分析,结果显示,本试验条件下所得棉籽分离蛋白(CPI)属酸溶性蛋白质,在酸性条件下(pH1～4)溶解性较好(30%～50%),在近中性溶液中溶解性较差,仅20%左右;乳化性受pH值、离子强度和CPI浓度影响不显著;乳化能力较低,但所得乳状液非常稳定;起泡性受pH值、离子强度和CPI浓度等因素影响很大,在中性pH下最高;添加NaCl对CPI溶液起泡能力影响不大,但会显著影响CPI溶液泡沫稳定性,随NaCl浓度增加,溶液泡沫稳定性急剧降低。粘度分析表明,CPI溶液属典型非牛顿流体,有"剪切变稀"和"热变稀"特征。

In order to improve the utilization of cottonseed protein in food industry, some functional properties of cottonseed protein isolates （ CPI ） were investigated in this paper. The results showed that the CPI had highly solubility in acid, about 30%-50% （ pH 1-4 ）. But poorly in neutral solution, only 20%. The emulsification of CPI was little affected by pH value, ion intensity and the CPI concentration. The emulsify capability of the CPI is low, but the emulsion system was ve.ry stable. The foaming property of the CPI was significantly affected by pH value, ion intensity and the CPI concentration, and to the highest point in neutral solution. The addition of NaCl to the CPI solution can markbly influenced to the foaming stability but little to its foaming capability. The foaming stability rapidly induced with the increasing of NaCl addition in CPI solution. The results of viscosity analyse indicated that the CPI solution was the typical non-Newtonian fluid, which had the characters of ＂shear thinning＂ and ＂heat thinning＂.