临汾常见食品中甲醛含量测定

Determination of Formaldehyde Content of Common Foods in Linfen

比较研究高效液相色谱法和乙酰丙酮法快速检测食品中甲醛。高效液相色谱法是在酸性条件下甲醛与2,4-二硝基苯肼反应生成甲醛-2,4-二硝基苯腙,用液相色谱分析(检出限0.05 mg/kg);乙酰丙酮法是在过量铵盐存在条件下乙酰丙酮和甲醛显色检测食品中甲醛含量(检出限0.015 mg/kg),并对2种方法的加热时间、加热温度、反应溶剂的添加量等反应条件进行优化。优化后的前者回收率为21.9%~52.5%,RSD(n=6)为2.85%,而乙酰丙酮法加标回收率达85.3%~90.2%,RSD(n=6)为2.06%。选取乙酰丙酮法测得样品中甲醛含量:白糖0.30 mg/kg,鱿鱼卷0.59 mg/kg,可口可乐0.52 mg/kg,红糖0.48 mg/kg,青岛啤酒0.06 mg/kg,腐竹0.02 mg/kg,血块0.01 mg/kg。

The acetylacetone method and high performance liquid chromatography（HPLC） method were compared to measure formaldehyde in food. Determination of formaldehyde-2, 4-dinitrophenylhydrazone formed by the reaction of formaldehyde with 2, 4-dinitrophenylhydrazine under acidic conditions was conducted by HPLC（detection limit 0.05 mg/kg）, and the acetylacetone method（detection limit 0.015 mg/kg） was used to determine the content of formaldehyde in food by detecting the products color of acetylacetone and formaldehyde in the presence of excess ammonium salts. In addition, the reaction conditions of both methods were optimized including heating time, heating temperature, and amount of reaction solvent. The recovery rate of the former was 21.9%-52.5% and RSD（n=6） was 2.85%. The recovery of acetylacetone was as high as 85.3%-90.2% and RSD（n=6） was 2.06%. The content of formaldehyde in the samples was determined by acetylacetone method which were sugar 0.30 mg/kg, squid volume 0.59 mg/kg, coca cola 0.52 mg/kg, brown sugar 0.48 mg/kg, Qingdao beer 0.06 mg/kg, yuba 0.02 mg/kg and blood clot 0.01 mg/kg.