连续流动注射法快速测定食品接触材料及制品中游离酚的含量

Rapid determination of free phenol in food contact materials and articles by continuous flow injection analyzer

建立利用连续流动注射法(continuous flow injection analyzer)测定食品接触材料及制品中游离酚含量的快速测定方法。采用凯氏定氮蒸馏仪对样品进行蒸馏,蒸出溶液中游离酚利用流动注射法进行定量分析。经过主要参数的优化,选择蒸馏时间为18 min和蒸汽量为60%、出峰时间为19s,外标法定量。结果显示,该检测方法可在18 min内完成游离酚的蒸馏,方法灵敏度高,检出限低至5 mg/kg,相关系数R2>0.998,在5 mg/kg、25 mg/kg、100 mg/kg 3个浓度水平下的加标回收率为83%~102%,相对标准偏差为1.8%~4.2%(n=6)。对3种类型共60批次实际样品进行了检测,聚碳酸酯类产品检出率为36%,水基改性环氧树脂涂料和环氧酚醛涂料产品检出率分别为4%和8%,游离酚含量范围在14~460 mg/kg之间。该方法灵敏度高,精密度和准确度好,与滴定法和分光光度法相比,能有效提升方法灵敏度和检测效率,适用于食品接触材料与制品中游离酚含量的快速检测。

A rapid determination method for the content of free phenol in food contact materials and products using continuous flow injection analysis was established.The method involves distillation of the sample using a Kjeldahl nitrogen distillation apparatus,followed by quantitative analysis of free phenols in the distillate using a continuous flow injection analysis.After optimizing the key parameters,a distillation time of 18 minutes,a steam volume of 60%,and a peak elution time of 19 seconds were selected,and external standard method was used for quantification.The results showed that the detection method can complete the distillation of free phenols in about 18 minutes,with high sensitivity and a low detection limit of 5 mg/kg.The correlation coefficient R2 was>0.998,and the recovery rates at three concentration levels of 5 mg/kg,25 mg/kg,and 100 mg/kg ranged from 83%to 102%,with relative standard deviations of 1.8%to 4.2%(n=6).A total of 60 batches of actual samples from three types were tested,with detection rates of 36%for polycarbonate products,4%for water-based modified epoxy resin coatings,and 8%for epoxy phenolic coatings.The content of free phenols ranged from 14 to 460 mg/kg.This method exhibits high sensitivity,precision,and accuracy.Compared to titration and spectrophotometry methods,it effectively enhances sensitivity and detection efficiency,making it suitable for the rapid determination of free phenol content in food contact materials and products.