食品中铝含量测定方法的研究

Research of determination methods of food aluminum content

目的通过对食品中总铝含量测定方法的研究,探讨如何应用现行标准检测方法为含铝食品添加剂的管理提供更好的技术支持。方法应用电感耦合等离子体光谱技术和质谱技术,对不同基质的生物成分标准物质中铝含量进行定量分析,比较不同酸消解体系对总铝含量测定值的影响,并对面制品、水产品等样品进行铝本底值的测定。结果单硝酸体系并不能将样品完全消解,需加入适量氢氟酸消解才能准确测定总铝含量。大量食品中铝存在本底值,且部分贝类、海蜇等水产品中总铝的含量已经超过100 mg/kg的国家限量标准。结论应用铝的国家标准检测方法测定总铝含量,其结果偏低,需采用硝酸-氢氟酸消解体系方可准确测定总铝含量,如果相关规定中铝含量不以"总铝含量计",现行标准检测方法才可得以更好地应用,且不同基质食品有着不同铝的本底值,不同的检测方法也有不同的方法检出限,在管理含铝食品添加剂使用情况时,需综合考虑所使用的检测方法及样品基质本底情况进行科学的判别。

Objective To evaluate the analytical methods for determination of total aluminum in foodstuff. Methods Inductively coupled plasma optical emission spectrometer (ICP-OES) and inductively coupled plasma mass spectrometry(ICP-MS) were used to determine total aluminum in reference materials including different foodstuff samples. Digestion effects using different types of acid were compared. The background value of total aluminum was determined in flour and aquatic products.ResultsOnly nitric acid can not digest sample completely. Using nitric acid and hydrofluoric acid together could completely digest foodstuff samples. Aluminum was frequently detected in food samples and the level in parts of shellfish and jellyfish had exceeded 100 mg/kg.Conclusion Aluminum concentration detected by the method of national standard was lower than the true value. Using nitric acid and hydrofluoric acid together in the digestion step can precisely determine the total aluminum in foodstuff samples.