加工和贮藏条件对泥鳅多肽抗氧化活性的影响

Influence of processing and storage conditions on antioxidant activity of loach peptide

以泥鳅抗氧化多肽为研究对象,模拟加工和储存条件,探讨了温度、pH、光照、干燥方式、金属离子和食品配料对泥鳅多肽清除DPPH和ABTS自由基能力的影响.结果表明:在25～100℃范围内泥鳅多肽抗氧化活性变化不显著(P>0.05);日光照射下存放8周后,其清除DPPH和ABTS自由基的能力分别降低36.8%和25.9%(P<0.05);在pH值为2.0～7.0时抗氧化活性变化不显著,在碱性条件下活性丧失较快,pH值增加至10.0时,肽清除DPPH和ABTS自由基的能力分别降低90%和20%左右(P<0.05);Cu2+和Zn2+浓度的增加能显著降低其抗氧化活性(P<0.05),而Mg2+,Ca2+和K+则对其影响不显著;糖类对其抗氧化活性的影响大小顺序依次为:葡萄糖>蔗糖>海藻糖;冷冻和喷雾干燥方式对泥鳅肽抗氧化性的影响不存在显著差异.

The effects of temperature,pH,light,drying,metal ions and food ingredients on the DPPH and ABTS radical scavenging activities of a previously isolated loach peptide mix were investigated in order to determine the stability of the antioxidant peptides. The results showed that the antioxidant activity of the peptide didn＇t change significantly at 25~100 ℃（P0.05）. DPPH and ABTS radical scavenging activity were decreased by 36.8% and 25.9% in the sunlight over 8 weeks（P0.05）. The peptide was stable for pH 2.0~7.0,but DPPH and ABTS radical scavenging activities were significantly reduced to about 90% and 20% at pH 10.0. The Cu2＋ and Zn2＋ at an increasing concentration significantly decreased the antioxidant activity of loach peptide. Mg2＋,Ca2＋ and K＋ ions（P0.05） had no effect. The antioxidant activity of loach peptide was improved by sugar in the order of glucose sucrose trehalose. Lypholization and spray drying showed no significant difference on its antioxidant activity.