基于非线性化学指纹图谱的羊乳广谱掺假检测研究

Untargeted Detection of Caprine Milk Adulteration by Nonlinear Chemical Fin⁃gerprint Method

目前羊乳中发现的掺假物质种类繁多,而检测方法多为针对单一掺假物质的检测。本研究基于非线性指纹图谱技术构建非特异性的广谱掺假物质判定方法。本研究在测定32个纯山羊乳样品及添加5%、1%和0.1%不同浓度氯化钠、大豆蛋白胨、尿素和蔗糖羊乳样品的非线性指纹图谱基础上,对纯山羊乳与掺假羊乳的指纹图谱进行直观的比较和相似度比较。添加0.5%以上氯化钠或尿素的掺假样品和5%以上大豆蛋白胨或蔗糖的掺假样品与纯生鲜羊乳的指纹图谱明显不同,可判定为掺假羊乳。以纯羊乳样品最低相似度值为临界值,则含0.5%和1%蔗糖的掺假样品相似度值在临界值上下,其余掺假样品的相似度值均小于临界值83.4%。故对生鲜乳中添加以上四种掺假物质浓度大于5%的掺假行为通过指纹图谱的直观比较和相似度值比较均可判定为掺假,该方法可用于生鲜羊乳的掺假检测,一次检测即可排除多种掺假物质的存在。

Many adulterants were added to milk for economically motivated adulteration,whereas the traditional analysis methods were adul⁃terant-specific approaches.It is urgent to set up an untargeted and universal method to appraise milk products for economically motivated adulteration.In this study,nonlinear chemical fingerprint of pure caprine milk(PCM)and adulterated caprine milk(ACM)with sodium chlo⁃ride,soybean peptone,urea and sucrose at concentrations of 5,1 and 0.5%were analyzed.There are significantly differences between the fin⁃gerprint figures of PCM and ACM with more than 0.5%sodium chloride or urea and more than 5%soybean peptone or sucrose.While the similarity values of ACMs except the samples with sucrose in 0.5%and 1%are all under the critical value(83.4%)which equal to the lowest similarity of PCM.The result indicates that the method can be used for detection of economically motivated adulteration.