以抗氧化活性及蛋白质回收率为筛选指标对乳清蛋白肽酶解工艺进行优化，用层析柱对酶解液进行逐级分离纯化，并对其分子质量进行检测． 研究结果表明:利用胰酶、复合风味蛋白酶、木瓜蛋白酶和碱性蛋白酶酶解制备乳清蛋白肽，最佳用酶为碱性蛋白酶、最适底物含量为4. 0%、最适加酶量为8000U/g、最佳酶解时间为4h;酶解液经 DEAE-52 纤维素层析后得到的 A 组分抗氧化活性最好，其还原力为 0. 3200 ±0. 0041，DPPH 自由基清除率为6. 58% ±0. 36%;A 组分再经 Sephadex G-15 葡聚糖凝胶层析柱分离纯化后得到组分 G，其 DPPH 自由基清除率为 6. 73% ±0. 083%;组分 G 的主要成分为分子质量378u 的肽段，其一级氨基酸组成为赖氨酸(Lys)、亮氨酸(Leu)及丝氨酸(Ser)．

Whey protein peptides were prepared via enzymolysis，and the corresponding conditions were optimized by taking antioxidant activity and protein recovery as two indicators． Then，the enzymatic hydrolysate was separated and purified by means of column chromatography，and the molecular mass of the product was measured． The results indicate that (1) alkaline protease is more suitable for the enzymolysis than trypsogen，flavorzyme and papain，with an optimal substrate dosage of 4． 0%，an optimal enzyme dosage of 8000U/g and an optimal enzymolysis time of 4h; (2) fraction A obtained by DEAE-52 cellulose column chromatography exhibits the highest antioxidant activi-ty，with a reducing power value of 0． 3200 ±0． 0041 and a DPPH radical scavenging activity of 6． 58% ±0． 36%;(3) further separation of fraction A via Sephadex G-15 gel column chromatography helps to obtain fraction G with a DPPH radical scavenging activity of 6． 73% ±0． 083%; and (4) the main component identified from fraction G，which contains three amino acids (namely Lys，Leu and Ser)，is of a molecular mass of 378u．