Larsson B K
J Assoc Off Anal Chem. 1983 May;66(3):775-80.
A gas-liquid chromatographic method for the simultaneous determination of benzoic acid and sorbic acid in foods was collaboratively studied by 8 laboratories. Benzoic and sorbic acids are isolated from food by successive extractions with ether, sodium hydroxide, and methylene chloride, converted to trimethylsilyl (TMS) esters, and determined by gas-liquid chromatography. Phenylacetic acid and caproic acid are used as internal standards for benzoic acid and sorbic acid, respectively. Seven samples were collaboratively studied: almond paste, fish homogenate, and apple juice with benzoic and sorbic acid levels from 0.04 to 2 g/kg. Average recoveries (%) for benzoic and sorbic acids were as follows: almond paste, 99.6 and 101.2; fish homogenate, 99.2 and 97.4; and apple juice 98.2 and 106.6. The reproducibility coefficients of variation (%) for benzoic and sorbic acids at 0.5-2 g/kg levels were 3.5-6.1 and 5.2-9.0; and at the 0.04 g/kg level, 14.7 and 23.3, respectively. The method has been adopted official first action at 0.5-2 g/kg levels.
8个实验室共同研究了一种同时测定食品中苯甲酸和山梨酸的气液色谱法。通过用乙醚、氢氧化钠和二氯甲烷连续萃取从食品中分离出苯甲酸和山梨酸，将其转化为三甲基硅烷基（TMS）酯，并用气液色谱法进行测定。分别用苯乙酸和己酸作为苯甲酸和山梨酸的内标。对7个样品进行了协同研究：杏仁酱、鱼肉匀浆和苹果汁，苯甲酸和山梨酸含量为0.04至2 g/kg。苯甲酸和山梨酸的平均回收率（%）如下：杏仁酱，99.6和101.2；鱼肉匀浆，99.2和97.4；苹果汁，98.2和106.6。苯甲酸和山梨酸在0.5 - 2 g/kg水平的重现性变异系数（%）分别为3.5 - 6.1和5.2 - 9.0；在0.04 g/kg水平分别为14.7和23.3。该方法已在0.5 - 2 g/kg水平作为官方首次采用方法。
