水解度对麦胚清蛋白酶解物功能特性和抗氧化力影响

利用碱性蛋白酶限制性酶解麦胚清蛋白,研究不同水解度(degree of hydrolysis,DH)酶解物的溶解性、乳化性等功能特性,及对DPPH自由基和羟自由基清除等抗氧化能力。实验结果表明,水解后清蛋白酶解物的溶解性得到改善,DH越高溶解性越好。DH为8.34%时,等电点处的溶解度从未水解时的49.52%提高到74.09%。而乳化性和乳化稳定性随DH的增加而降低。当DH低于7.54%时,酶解物对DPPH自由基和对羟自由基的清除率随DH的提高而增强。浓度为100 mg/mL,DH为7.54%时的酶解物对DPPH自由基清除率达到59.68%。浓度为5 mg/mL时,DH为7.54%时的酶解物对羟自由基清除率达50.23%。 

Effect of degree of hydrolysis on functional characteristics and antioxidant properties of wheat germ albumin hydrolysates

Alkaline protease was used to digest wheat germ albumin restrictively. The effects of DH on the hydrolysates 'functional characteristics and antioxidant activity were studied, including solubility, emulsifying, DPPH radical-scavenging activity and hydroxyl radical-scavenging activity. The results showed that the solubility of the hydrolysate was improved after hydrolysis.The higher the DH, the better the solubility.The solubility at the soelectric point increased from 49.52% to 74.09%when the DH was 0 and 8.34%, respectively.The emulsifying properties decreased with the increase of DH.When the DH was lower than 7.54%, the DPPH radical-scavenging activity and hydroxyl radical-cavenging activity of the hydrolysates increased with the DH.When the DH was 7.54% and the concentration was 100 mg/mL, the DPPH radical-scavenging rate was 59.68%.When the DH was 7.54% and the concentration was 5 mg/mL, the hydroxyl radical-cavenging rate was 50.23%.