燕麦麸分离蛋白的酶解对其功能性质的影响

Effects of enzymatic hydrolysis on the functional properties of oat bran protein isolates

为了改善燕麦蛋白的功能性质以扩大其在食品工业中的应用,该文以燕麦麸为原料制备了燕麦麸分离蛋白(OBPI),并利用胰蛋白酶对其进行水解,得到了3种不同水解度(4.1%、6.4%、8.3%)的酶解产物。SDS-PAGE分析结果表明OBPI中的主要蛋白成分是球蛋白,其经过胰蛋白酶处理后,球蛋白酸性亚基被部分水解而碱性亚基相对保持完整。胰蛋白酶水解显著改变了OBPI的功能性质。在所考察的水解度范围内,随着水解度的升高,酶解产物的溶解性、持水性、乳化活性及起泡能力等方面均逐渐增加;但持油性、乳化及泡沫稳定性有不同程度的降低。

In order to improve the functional properties of oat protein and extend its application in food industry, oat bran protein isolates （OBPI） were prepared from oat bran and hydrolyzed by using trypsin. Protein hydrolysates of three different degrees of hydrolysis（DH）（4. 1%, 6.4% and 8.3% respectively） were obtained. Sodium dodeeyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） analysis results show that oat globulin is the major protein component in OBPI. After trypsin treatment, acidic polypeptides of globulin were partly degraded; however, basic polypeptides were almost intact. The functional properties of products were compared with those of control OBPI. Marked changes in the protein functionality were caused by proteolysis. The solubility, water-holding capacity, emulsifying activity and foaming ability of hydrolysates increased gradually with the increase of DH. However, the oil-holding capacity, emulsifying stability and foaming stability of the hydrolysates reduced to a certain extent.