为制备低钠盐含量的葵花籽粕蛋白血管紧张素转换酶抑制肽(ACEI抑制肽),建立了以Ca(OH)2溶液调节酶解反应pH值的制备工艺并进行了工艺参数优化。以蛋白水解度、产物ACE抑制率和苦味值为评价指标通过选酶试验从6种商业蛋白酶中确定胰蛋白酶为水解用酶。通过对葵花籽粕蛋白酶解试验,发现在其他酶解条件相同情况下,以Ca(OH)2调节酶解pH值的葵花籽粕水解多肽的ACE抑制率和水解度优于NaOH调节的,而苦味值相近。通过对底物浓度、加酶量、pH、温度和时间进行单因素试验和对时间、温度、pH等因素进行的正交优化试验,确定用Ca(OH)2调节酶解pH值的制备葵花籽粕蛋白ACEI抑制肽工艺参数为:底物的质量浓度为3.5%,加酶量2.85%(E/S),pH7.5、温度45℃和酶解时间5min,所得ACEI抑制肽产品的IC50值为6.06mg/mL。

To produce low sodium salt angiotension converting enzyme (ACE) I inhibitory peptides from sunflower seed meal protein,the digestion techniques with Ca(OH)2 as pH adjusting reagent (pHAR) was established and optimized.Assessed by degree of hydrolysis (DH),ACE inhibitory rate,and bitterness of peptides,trypsogen was chosen from six commercial proteases to use as digestive enzyme in this study.Based on enzymolysis reactions with NaOH or Ca(OH)2 solution as pHAR,it was observed that at same conditions of digestion except pHAR,the ACE inhibitory rate and DH of sunflower seed meal peptides (SSMP) with Ca(OH)2 as pHAR were higher than those with NaOH as pHAR,and the bitterness of two kinds of SSMPs were quite close.According to single factor experiments on substrate content (SC),trypsogen content (TC),pH value,digestion temperature (DT),and digestion time (Dt),and orthogonal test on pH,DT,and Dt,the optimal digestion conditions were determined as:SC 3.5% (m/v),TC 2.85% (E/S),pH 7.5,DT 45℃,and Dt 5 min.And the 50% ACE inhibitory content (IC50 value) of SSMP under the optimal condition was 6.06 mg/mL.