酪蛋白质量分数作为乳品掺假检验指标的探讨

Discussion on mass fraction of casein as an index for adulteration testing in milk and milk products

论述了我国乳品掺假的原因、方式和危害,以及掺假鉴定的必要性和重要性,分析了酪蛋白是牛乳中的特征性成分,根据乳品中酪蛋白占乳蛋白的质量比例(即酪蛋白质量分数)一般会稳定在77%～78%左右,提出了酪蛋白质量分数≥73%,可以作为乳品掺假检验的定量指标,探讨了国内外酪蛋白定量检测方法的研究现状。结果表明,等电点沉淀法无疑是一种适合我国国情的、操作简单的酪蛋白检验方法,对防治乳品掺假具有重要的现实意义,并通过分析提出了该检验方法所需研究的内容。

The causes, manners and hazards of adulteration in milk and milk products in China, and essentiality and importance of adulteration assessment, were described and discussed. It is well known that casein is a characteristic component of milk. The mass proportion of casein in milk proteins, namely Mass Fraction of Casein, is generally within the range of 77%-78%. Therefore, Mass Fraction of Casein（g/g protein）（≥ 73%）, may become a quantitative index for adulteration testing in milk and milk products. The research status of the quantitative testing methods of casein at home and abroad was discussed. The results showed that isoelectric precipitation was a reliable method for casein testing fitting to Chinese status and having a simple operation which have important realism significance for preventing adulteration in milk and milk products. The study contents about this testing method had been put forward through analysis.