乳粉中蛋白质测定条件的改进

目的对乳粉中蛋白质测定条件进行改进，以便于实验的操作和控制。方法参照中华人民共和国国家标准《食品中蛋白质的测定》（GB／T5009．5—2003）对《婴幼儿配方食品和乳粉蛋白质的测定》（GB／T5413．1—1997）中的试样前处理和消化液的蒸馏2个重要步骤用同一乳粉进行蛋白质含量的测定比对。结果测定条件改进前后所测同一乳粉中蛋白质含量结果无差异性。结论改进后的测定条件在乳粉中蛋白质测定时容易操作和控制，不易导致测定实验失败。

Improvement on Determination Conditions of protein in milk powder

Objective] To improve the determination conditions of protein in milk powder for easier operation and control of experiment. Methods ] According to the national standard Determination of protein in foods （ GB/T 5009.5 - 2003 ）, the conditions of sample pre-treatment and extractive distillation were improved, which were two important steps in Determination of protein in Milk powder and formula foods for infants. The protein contents of a same milk powder sample of different conditions were compared. Restults ] There was no difference in the protein contents of a same milk powder sample between before and after improvement of determi- nation conditions. Conclusion] The improved conditions are easy for operation and control in determination of protein in milk powder, and it will not cause the failed experiment.