棉籽分离蛋白的功能特性研究  

Functional property of cottonseed protein isolate

作　　者：赵小龙[1] 刘大川[1] 

机构地区：[1]武汉轻工大学食品科学与工程学院,武汉430023

出　　处：《中国油脂》2015年第1期27-30,共4页China Oils and Fats

摘　　要：为了探讨棉籽分离蛋白在食品工业中应用的可能性,研究了pH、温度、蛋白质溶液质量分数对棉籽分离蛋白的溶解性、持水性、吸油性、起泡性及乳化性等功能特性的影响。结果表明,在pH 4-5之间时,棉籽分离蛋白溶解性最低,氮溶指数（NSI）仅为2.11%。当pH大于5,棉籽分离蛋白溶解性逐渐增加,在pH达到11之后,棉籽分离蛋白几乎全部溶解,氮溶指数为93.8%。在pH 4-6之间时,棉籽分离蛋白持水性基本保持不变,当pH大于6,其持水性显著升高。在pH等于7时,棉籽分离蛋白的起泡性、乳化性均随着蛋白质溶液质量分数增大而增大,而泡沫稳定性及乳化稳定性受蛋白质溶液质量分数影响较小；棉籽分离蛋白吸油性随着温度升高而逐渐减小。通过差示扫描量热仪测定,棉籽分离蛋白的变性温度为95.18℃,高于大豆分离蛋白的变性温度88.64℃,变性热焓为137.6 J/g,低于大豆分离蛋白的变性热焓178.7 J/g。通过物性测试仪测定,棉籽分离蛋白所形成的凝胶比同等条件下大豆分离蛋白所形成凝胶的凝胶强度大。In order to explore the application possibility of cottonseed protein isolate in food industry,the impacts of pH,temperature and mass fraction of protein solution on the functional properties of cottonseed protein isolate including solubility,water holding capacity,oil absorption,foamability,emulsifying property etc were studied. The results showed that the solubility of cottonseed protein isolate was the lowest and NSI（nitrogen soluble index）was only 2. 11% at pH 4-5;when pH was higher than 5,its solubility in-creased gradually;when pH was above 11,cottonseed protein isolate was almost completely dissolved and the NSI reached 93 . 8%. The water holding capacity of cottonseed protein isolate basically unchanged at pH 4-6,when pH was higher than 6,its water holding capacity improved markedly. When pH was 7,the foamability and emulsifying property of cottonseed protein isolate increased with the increase of mass frac-tion of protein solution,while its foam stability and emulsion stability were less affected. Its oil absorption decreased with temperature rising. The denaturation temperature of cottonseed protein isolate determined by differential scanning calorimetry was 95. 18℃,higher than that of soybean protein isolate （88. 64℃）, and its denaturation enthalpy was 137. 6 J/g,lower than that of soybean protein isolate（178. 7 J/g）. The gel strength of the gel from cottonseed protein isolate determined by physical tester was larger than that from soybean protein isolate under the same condition.

关 键 词：棉籽分离蛋白 功能特性 热稳定性 凝胶强度 

分 类 号：TS229[轻工技术与工程—粮食、油脂及植物蛋白工程] TQ936.2[轻工技术与工程—食品科学与工程]