目的：采用微波消解-电感耦合等离子体质谱法(ICP-MS)快速鉴别巧克力中的可可脂来源。方法分别准确称取巧克力和代可可脂巧克力及可可原材料0.5000 g,加入5 mL浓硝酸经微波消解后定容至50 mL,上机检测铜离子含量。结果铜元素在添加水平为0.10、0.15 mg/kg的回收率为90.52%~100.83%,方法精密度1.4%,方法检出限为0.5 mg/kg。巧克力中铜元素含量大小关系：可可固形物50%以上＞可可固形物50%以下＞代可可脂巧克力。巧克力中可可固形物含量在85%以上铜元素含量和可可固形物和可可粉中的铜元素含量相当。结论通过ICP-MS法快速检测巧克力中的铜元素可以简单便捷地鉴别巧克力中可可脂来源属性。%ABSTRACT:Objective To rapid identification of the source of cocoa butter in chocolate by inductively coupled plasma-mass spectrometry (ICP-MS) with microwave digestion. Methods The chocolate, cocoa butter chocolate and cocoa raw materials were accurately took 0.5000 g, respectively, added 5 mL concentrated nitric acid for microwave digestion and fixed capacity to 50 mL. The content of copper was analyzed. Results The recoveries of the method with the spiked levels of 0.10 and 0.15 mg/kg were 90.52%~100.83%, the relative standard deviation (RSD) was less than 1.4%, and the detection limit was 0.5 mg/kg. The order of content of Cu in chocolate were as follows:cocoa solids above 50%>cocoa solids below 50%>cocoa butter replacers. The content of Cu in chocolate with cocoa solids above 85%was comparable to the Cu content in cocoa solids and cocoa powder. Conclusion The proposed method is feasible to identify the source of cocoa butter in chocolate simply and conveniently.
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