气相色谱法测定高分子食品包装材料中抗氧化剂的残留量

建立了气相色谱测定高分子食品包装材料中抗氧化剂丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)和特丁基对苯二酚(TBHQ)残留量的分析方法。用环己烷超声萃取高分子食品包装材料样品,考察了萃取时间、温度对抗氧化剂萃取量的影响。萃取液经气相色谱柱HP-50+毛细管柱(30 m×0.53 mm×1 μm)分离,电子捕获检测器(ECD)检测,外标法定量。结果表明: 在抗氧化剂添加量为3.00～10.0 mg/kg范围内,BHT、BHA、TBHQ在高分子食品包装材料中的平均添加回收率分别为88%～93%、92%～101%和83%～97%,相对标准偏差(RSD, n=5)分别为2.01%～2.89%、2.11%～3.19%和2.99%～4.02%;检出限(信噪比为3)分别为0.5、0.5和0.8 mg/kg。对实际高分子食品包装材料样品的检测结果表明3种抗氧化剂在不同材质中均有检出: 塑料材料中抗氧化剂的含量较少,仅有BHT、BHA被检出,含量为6.3～7.8 mg/kg;橡胶材料中3种抗氧化剂均被检出,含量为9.3～28.4 mg/kg。该方法准确、灵敏、重现性好,适用于高分子食品包装材料中抗氧化剂残留量的检测。

Determination of antioxidant residues in polymer food package using gas chromatography

A new method for the determination of antioxidants, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and tertiary butylhydroquinone (TBHQ) in plastic food package by gas chromatography-electron capture detection (ECD) was developed. The antioxidants were extracted by cyclohexane with ultrasonic extraction, separated by an HP-50 + chromatographic column (30 m x 0.53 mm x 1 microm) and quantified by external standard method with an ECD detector. The average recoveries of antioxidants were 88% -93%, 92% - 101% and 83% -97% for BHT, BHA and TBHQ, respectively, at the spiking levels of 3.00 - 10.0 mg/kg. The corresponding relative standard deviations (RSDs, n = 5) were 2.01% - 2.89%, 2.11% - 3.19% and 2.99% - 4.02%, respectively. The limits of detection (S/N = 3) were 0.5, 0.5 and 0.8 mg/kg for BHT, BHA and TBHQ, respectively. The proposed method has been applied to the analysis of 5 kinds of polymer food package. The results indicated that all the above antioxidants were found in the practical polymer food package samples. Plastic food package contained BHT and BHA with the concentrations varying from 6.3 to 7.8 mg/kg and rubber food package contained all the three antioxidants with the concentrations varying from 9.3 to 28.4 mg/kg. This method is accurate, sensitive, highly reproducible and suitable for the analysis of residual antioxidants in polymer food package.