[ Objective] To study lipid oxidation of whole milk powder under different storage temperature. [ Method] The effects of time and temperature on lipid oxidation of whole milk powder were studied with TBA value as evaluation index, and the kinetic analysis of both the extent and the rate of lipid oxidation were respectively investigated. [ Result] The results showed that the relationship between lipid oxidation and time can be described by a first order model when storage temperature is from 30 ℃ to 40 ℃ , and can be described by both a first order model and a more accurate zero order model when storage temperature is from 50 ℃. The activation energy of lipid oxidation of whole milk powder fit to a first order model is 29. 81 kJ/mol. [ Conclusion] The rate constant of lipid oxidation with storage temperature from 30 ℃ to 50 ℃ can be calculated by using the kinetic model between lipid oxidation and temperature.%[目的]研究全脂奶粉在不同贮存温度下的脂肪氧化行为.[方法]选用硫代巴比妥酸值(TBA值)为评价指标,考察了温度和时间对全脂奶粉脂肪氧化的影响,并分别对脂肪氧化程度和脂肪氧化速率进行了动力学分析.[结果]当保存温度在30～40℃时,脂肪氧化随时间的变化符合一级反应动力学；当温度为50℃时,脂肪氧化随时间的变化同时符合一级和零级反应动力学,但是零级反应动力学更准确.全脂奶粉脂肪氧化一级反应动力学的活化能Ea为29.81 kJ/mol.[结论]利用脂肪氧化速率随温度变化的动力学模型,可以预测30 ～ 50℃任意温度下的全脂奶粉脂肪氧化速率常数.
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