不同方法提取乳清浓缩蛋白的研究

目的]探索一条经济、简单易行的乳清浓缩蛋白提取工艺。方法]以乳清废液为原料,分别采用醇沉法、碱沉法、醇＋碱沉法提取其中的乳清浓缩蛋白,比较不同方法的提取效果。结果]影响醇沉法提取乳清蛋白产量的因素依次为：沉淀时间〉乙醇浓度〉沉淀温度,最佳醇提条件为：乙醇浓度100%,沉淀温度50℃,沉淀时间1.5 h;影响碱沉法提取乳清蛋白产量的因素依次为：沉淀时间〉pH值〉沉淀温度,最佳碱提条件为：pH值10,沉淀温度30℃,沉淀时间1.5 h;影响醇＋碱沉法提取乳清蛋白产量的因素依次为：沉淀时间〉沉淀温度〉pH值〉乙醇浓度,最佳提取条件为：乙醇浓度90%,沉淀时间2.0 h,pH值7,沉淀温度20℃。结论]醇＋碱沉法提取乳清浓缩蛋白的效果最佳。

Study on Extracting Concentrated Milk Serum Protein by Different Methods

Objective]The aim was to explore an economic,simple and easy-to-operate extraction technology of concentrated milk serum protein.Method]With waste liquid of milk serum as raw material,the concentrated milk serum protein was extracted by using alcohol precipitation,alkali precipitation and alcohol+alkali precipitation and the extraction effect of different methods was compared.Result]The factors influencing milk serum protein output for extraction using alcohol precipitation were as follows:precipitation time>alcohol concn.>precipitation temperature and its optimum condition was as follows:the alcohol concn.was 100%,the precipitation temperature and time were 50 ℃ and 1.5 h resp.The factors influencing milk serum protein output for extraction using alkali precipitation were as follows: precipitation time>pH value>precipitation temperature and its optimum condition was as follows:the pH value was 10,the precipitation temperature and time were 30 ℃ and 1.5 h resp.The factors influencing milk serum protein output for extraction using alcohol+alkali precipitation were as follows: precipitation time>precipitation temperature>pH value>alcohol concn.and its optimum condition was as follows:the alcohol concn.,the precipitation time,pH value and precipitation temperature were 90%,2.0 h,7 and 20 ℃ resp.Conclusion]The effect of extracting concentrated milk serum protein using alcohol+alkali precipitation was best.