紫外分光光度法测定食品模拟物中六价铬和铝

Determination of chromium(Ⅵ) and aluminium in food simulates by ultraviolet spectrophotometry

建立食品模拟物中铝和六价铬的紫外分光光度测定方法。用含内涂层的金属饮料罐(两片罐和三片罐)分别盛装水、3%乙酸水溶液、10%乙醇水溶液,于40℃浸泡240h,得到食品模拟物。水、3%乙酸水溶液食品模拟物样品直接测定,10%乙醇水溶液食品模拟物经蒸发乙醇再测定。采用二苯碳酰二肼分光光度法测定六价铬,铬天青S分光光度法测定铝。六价铬的方法检出限为10ng/mL,方法回收率在82.0%～101%;铝的方法检出限为25ng/mL,回收率在82.2%～108%。该方法准确度高,操作简单。

Methods for determination of aluminium and chromium（Ⅵ） in food simulants by ultraviolet spectrophotometry were established.Beverage cans were filled with different kinds of food simulants and kept in thermostat at 40 ℃ for 240 h.Aluminium was determined by chrome azurol S spectrophotometric method.Chromium（Ⅵ） was determined by 1,5-Dtphenylcarbohydrazide spectrophotometric method.The detection limits were 10 ng/mL for Cr（VI） and 25 ng/mL for Al.The average recoveries were from 82.0% to 101% for Cr（Ⅵ）,and 82.2% to 108% for Al.The migration of Al from metal cans to food simulants was also discussed.The method for determination of Cr（Ⅵ） and Al in food simulants is precise and simple.