Influence of processing and storage conditions on antioxidant activity of loach peptide
1.College of Light Industry and Food Sciences,South China University of Technology,Guangzhou,Guangdong 510640,China; 2.Department of Food Science,Cornell University,Ithaca,New York 14853,USA）
Abstract：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.
2009, Vol. 30 
