DHA油脂在精炼过程中氧化稳定性的变化
Oxidative stability of DHA oil during the refining process
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摘要: 分析了DHA毛油依次经历脱胶、碱炼、脱色、脱臭等环节后,油脂的微组成及氧化稳定性变化。结果显示,在整个精炼过程中各微组分的含量整体呈下降趋势。DHA油脂对光稳定性:精油>脱色油>毛油/脱胶>碱炼油;DHA油脂对热稳定性(Rancimat法):脱色油>精油>脱胶油>毛油>碱炼油。DHA油脂在脱色环节之前,氧化稳定性差归因于其中促进氧化的微组分过多。在脱色环节之后油脂对热稳定性变差,归因于内源性的抗氧化组分在脱臭环节中大量损失。Abstract: The composition and oxidative stability of DHA oil was investigated during the refining process (deguming, alkali refining, bleaching and deodorization) .It was found that all of minor compounds decreased during the whole process.The order of oxidative stability of DHA oil against light was deodorized>bleached>crude/degummed>alkali refined oil.The order of oxidative stability of DHA oil against heat (Rancimat method) was bleached>deodorized>degummed>crude>alkali refined oil.The oxidative stability of DHA oils before bleaching step was poor because of too many prooxidants in oils, and the deodorized oil was less stable against heat due to the loss of antioxidants in the deodorization.