In the pet food scandal, nitrogen from melamine was indistinguishable from amino-acid nitrogen and contributed to the tally used to calculate the protein in the sample.

• 在上述的宠物食品丑闻里，因为无法区别出来来自三聚氰胺的氮与来自胺基酸的氮，结果在计算样本中的蛋白质含量时，这些氮都计算进去了。