三聚氰胺假蛋白原理Melamine-off theory

三聚氰胺假蛋白原理

来源：百度 作者： 发布时间：2008.09.16

由于食品和饲料工业蛋白质含量测试方法的缺陷，三聚氰胺也常被不法商人用作食品添加剂，以提升食品检测中的蛋白质含量指标，因此三聚氰胺也被人称为“蛋白精”。 蛋白质主要由氨基酸组成，其含氮量一般不超过30%，而三聚氰胺的分子式含氮量为66％左右。通用的蛋白质测试方法“凯氏定氮法”是通过测出含氮量来估算蛋白质含量，因此，添加三聚氰胺会使得食品的蛋白质测试含量偏高，从而使劣质食品通过食品检验机构的测试。有人估算在植物蛋白粉和饲料中使测试蛋白质含量增加一个百分点，用三聚氰胺的花费只有真实蛋白原料的1/5。三聚氰胺作为一种白色结晶粉末，没有什么气味和味道，掺杂后不易被发现。 奶粉事件：各个品牌奶粉中蛋白质含量为15-20%（晚上在超市看到包装上还有标示为10-20%的），蛋白质中含氮量平均为16%。以某合格牛奶蛋白质含量为2.8%计算，含氮量为0.44%，某合格奶粉蛋白质含量为18%计算，含氮量为2.88%。而三聚氰胺含氮量为66.6%，是牛奶的151倍，是奶粉的23倍。每100g牛奶中添加0.1克三聚氰胺，就能提高0.4%蛋白质。 微溶系指溶质1g(ml)能在溶剂100～不到1000ml中溶解，三聚氰胺在水中微溶，在牛奶这种水包油型的乳液中溶解度未找到实验数据，本人觉得比水的溶解度要好一些，待验证。 Melamine-off theory Source: Baidu Author: Published: 2008.09.16 As the food and feed industry test the protein content of the defect, melamine unscrupulous traders also often used as a food additive to enhance the detection of food protein content indicators, the melamine was also known as the "sperm protein." The main protein from amino acid composition, its nitrogen content less than 30%, and the formula of melamine nitrogen content of 66%. General protein test, "Kjeldahl" measured by nitrogen content to estimate the protein content, add melamine will make the food protein content of the test on the high side, so that the poor quality of food through the food inspection agency of the test. It was estimated in the vegetable protein powder and protein content of feed, make the test by one percentage point increase in the use of melamine, only the true cost of raw materials protein 1 / 5. Melamine is a white crystalline powder, no smell and taste, not after doping was found. Milk powder incident: the various brands of milk protein content of 15-20% (in the supermarket that night package also marked as 10-20%), protein nitrogen content in an average of 16%. To pass a milk protein content of 2.8% to 0.44% nitrogen content, a qualified milk protein content of 18% to 2.88% nitrogen content. Melamine and 66.6 percent for the nitrogen content is 151 times that of milk, milk powder is 23 times. Add milk 100g per 0.1 grams of melamine, will be able to raise the 0.4 percent protein. Micro-dissolved solute means 1g (ml) in the solvent from 100 to less than 1000ml dissolved, melamine micro-soluble in water, milk in this oil-in-water emulsion of the type found in the solubility of experimental data, I feel better than the water solubility , To be verified.