Díaz Mariana, Dunn Christopher M, McClements D Julian, Decker Eric A
Department of Food Science, Chenoweth Laboratory, University of Massachusetts, Amherst, Massachusetts 01003, USA.
J Agric Food Chem. 2003 Apr 9;51(8):2365-70. doi: 10.1021/jf025984l.
Chelators are valuable ingredients used to improve the oxidative stability of food emulsions. Caseins and casein peptides have phosphoseryl residues capable of binding transition metals. Thus, the ability of enriched caseinophosphopeptides to inhibit lipid oxidation in corn oil-in-water emulsions was investigated. Enriched caseinophosphopeptides (25 microM) inhibited the formation of lipid oxidation at both pH 3.0 and 7.0 as determined by lipid hydroperoxides and hexanal. Calcium (0-100 mM) had no influence on the antioxidant activity of the enriched caseinophosphopeptides. Casein hydrolysates were more effective inhibitors of lipid oxidation than the enriched caseinophosphopeptides at equal phosphorus content. Thus, antioxidant properties might not be uniquely attributed to chelating metals by phosphoseryl residues but also by scavenging free radicals. Overall, the observed antioxidant activity of casein hydrolysates means they could be utilized to decrease oxidative rancidity in foods.
螯合剂是用于提高食品乳液氧化稳定性的重要成分。酪蛋白和酪蛋白肽含有能够结合过渡金属的磷酸丝氨酰残基。因此，研究了富含酪蛋白磷酸肽抑制水包油型玉米油乳液中脂质氧化的能力。通过脂质氢过氧化物和己醛测定，富含酪蛋白磷酸肽（25微摩尔）在pH 3.0和7.0时均抑制脂质氧化的形成。钙（0 - 100毫摩尔）对富含酪蛋白磷酸肽的抗氧化活性没有影响。在磷含量相等的情况下，酪蛋白水解产物比富含酪蛋白磷酸肽更有效地抑制脂质氧化。因此，抗氧化特性可能不仅归因于磷酸丝氨酰残基螯合金属，还归因于清除自由基。总体而言，观察到的酪蛋白水解产物的抗氧化活性意味着它们可用于降低食品中的氧化酸败。
