PVC密封圈中环氧大豆油向食品模拟物迁移量的测定

Migration of epoxidized soybean oil from PVC gaskets to food simulants

建立了气相色谱-质谱法（GC-MS）对食品玻璃包装瓶盖聚氯乙烯（Polyvinyl chloride polymer,PVC）密封圈中环氧大豆油（Epoxidized soybean oil,ESBO）向食品模拟物迁移量的检测方法。以蒸馏水和橄榄油为模拟物,在40℃条件下浸泡瓶盖240h,经甲酯化和衍生化,以11,14-二环氧二十烷酸乙酯为内标物,通过测定环氧亚油酸（18∶2 2E）衍生物的含量,进而定量测定ESBO的迁移量。结果表明：ESBO在0.5-50.0mg/kg的浓度范围内线性关系好,R2大于0.993,回收率在92.8%-103.9%之间,RSD为0.9%-8.0%（n=6）,检出限（LOD）为0.2mg/kg,定量限（LOQ）为0.5mg/kg,方法精密度好,灵敏度高,定性定量准确。最后,应用其对24种不同PVC密封圈中的ESBO迁移量进行测定,水基模拟物中ESBO的迁移量符合法规EC 10/2011限量,而在油脂模拟物中测得含量在0.7-501.8mg/kg之间,其中7种超过了限量要求。

A method was developed for determination of the migration of epoxidized soybean oil（ESBO） from PVC gaskets of glass jars in food simulant by gas chromatography-mass spectrometry（GC-MS） .The gaskets were exposured to distilled water and olive oil at 40℃ for 240h, and ESBO was treated by methyl esterification and derivatization.Ethyl 11,14-diepoxyeicosanoate was used as internal standard to determine the epoxy linoleic acid in ESBO for ESBO quantification by GC-MS.The results showed the calibration curves of ESBO was linear in the range of 0.5-50mg/kg with correlation coefficients not less than 0.993.The spiked recoveries at different spiked levels were in the range of 92.8%-103.9% with relative standard deviations （RSD）of 0.9%-8.0%.The limit of detection（ LOD）was 0.2mg/kg and the limit of quantitation（LOQ） was 0.5mg/kg.This method was precise,highly sensitive and accurate,which was applied in determination of the migration of ESBO in food simulants for 24 PVC gaskets.The results showed that the migration of ESBO in distilled water was lower than the regulations of EC 10/2011, but its content was between 0.7-501.8mg/kg and 7 of them exceeded the regulations in olive oil.