烘焙纸中残留甲苯向食品模拟物中迁移分析

Analysis of Migration of Residual Toluene from Baking Paper to Food Simulants

目的 研究烘焙纸中残留甲苯向食品中的迁移规律,并考察烘焙纸微观结构变化对迁移的影响。方法 采用气相色谱-串联三重四级杆质谱(GC-MS/MS)法,研究在不同烘焙温度、时间、纸张定量、甲苯初始浓度、微波加热等条件下,残留甲苯向橄榄油和改性聚苯醚(Tenax-TA)中的迁移规律,通过扫描电镜等技术手段,考察迁移前后烘焙纸微观结构的变化。结果 烘焙温度越高,甲苯迁移率越大;迁移率随迁移时间的延长而升高,但超过40 min后,甲苯向Tenax-TA中的迁移率出现明显下降趋势;纸张定量越大,迁移率越低;初始浓度对迁移率的影响不显著;微波功率越高,迁移率越大。随着微波时间的延长,迁移率呈先升高后降低的现象。扫描电镜结果表明,经过高温烘焙后,纸张纤维孔隙的尺寸及数量有所增加。结论 烘焙纸中残留甲苯在一定条件下向食品模拟物中发生迁移,纸张内部纤维结构的变化使甲苯分子更容易穿过孔隙进入食品中,加速了迁移的发生。

The work aims to study the migration law of residual toluene from baking paper to food and investigate the effect of baking paper microstructure on the migration. In this research, the GC-MS/MS method was used to analyze the migration law of residual toluene from baking paper into food simulants (olive oil, Tenax-TA) under different conditions of baking temperature, time, paper quantification, initial toluene content, microwave heating, etc., and the microstructure changes of baking paper before and after migration. The results showed that, the migration rate varied markedly with the temperature, with higher temperatures leading to accelerated migration. The longer the migration, the greater the migration rate. However, after the migration lasted for more than 40 min, the migration rate of toluene into Tenax-TA shifted to a downward trend significantly. The higher the gram weight of paper, the lower the toluene migration rate. The initial concentration of toluene in baking paper had no significant effect on the migration rate. The higher the microwave power, the higher the migration rate. As the microwave time lengthened, the migration rate rose first and then dropped. The scanning electron microscope (SEM) results suggested that baking at a high temperature could change the internal fiber structure of paper, and lead to an increasing size and number of fiber holes. Residual toluene in baking paper migrates to food simulants under certain conditions. This makes it easier for toluene molecules to pass through the pores into the food, thus accelerating migration.