高压脉冲电场对牛乳抗氧化能力的影响

Effects of Pulsed Electric Fields on Antioxidant Capacity of Milk

研究了高压脉冲电场(PEF)处理和热处理对牛乳总抗氧化能力和过氧化值的影响。采用牛乳对DPPH自由基的清除率来评价其抗氧化能力,用改进的IDF分光光度法测定了牛乳的过氧化值。结果表明:新鲜牛乳对DPPH自由基的清除率为49.65%,无论是低温长时(60℃、30min),高温短时(75℃、15s)巴氏杀菌,还是PEF(30kV/cm、400μs)处理,牛乳清除DPPH自由基的能力都略有下降,而过氧化值都有所升高。

In this study, the antioxidant capacity and lipid peroxidation of bovine milk subjected to thermal and PEF processing were investigated. ＂Diphenyl Pieryl Hydrazyl＂ （DPPH） assay was used to evaluate the radical-scavenging capacity of the milk, the peroxide value （POV） method was determined by the modified International Dairy Federation （IDF） Fe（Ⅱ）-oxidation-based spectrophotometric method. The results showed that the radical-scavenging capacity of fresh milk was 49.65% , and no matter whether the milk processed by PEF（30 kV/cm,400μs） or thermal processing （60℃ for 30 min or 75 ℃ for 15 s） , the antioxidant capacity was decreased and the primary oxidation value were increased.