Migration Behaviors And Prediction Of Phthalates From Microwave Paper To Tenax And Milk Powder

Food safety problem is not only can be caused by itself quality problem, it may be alsocaused by food packaging. In recent years, more and more people concern about the food safetyas a result of the migration of contamination from packaging to the food. Thus, the influencefactors of migration process for paper packaging were determined through experiments, whichwere researching on the migration of phthalates from microwave paper to the foodsimulant(Tenax) and milk powder. At the same time, the prediction model for migrating toTenaxand milk powder was builded up respectively basing on the Fick’s second law and the Weibulldistribution theory, in order to provide the basis for ensuring food safety.The migration of phthalates from microwave paper to Tenax and milk powder at differentheating temperature (100℃,70℃,50℃，30℃) showed rules as following:(1)The influenceof migration surrounding. The migration rate increased with time, and migration rate were fasterin early stage of migration and became more and more slow until reaching the balance ofmigration. The higher the temperature was, the higher the migration rate was.(2) The influenceof migrant.The phthalates with small molecular weight migrated easily and migrated more. Thephthalates with large saturated vapor pressure volatilized severely and migrated more becausethe nature of paper material is porous.(3) The influence of food.The different rules betweenmigrating to Tenax and milk powder showed that food characteristics affected the maximummigration and migration rate.The migration model under the finite packaging volume and finite food volume wasestablished basing on Fick’s second law and paper packaging characteristics. Firstly, to determineof migrating to Tenax and milk powder with Brandsch model and experimental data, and thediffusion coefficient formula for phthalates in microwave paper migrating to Tenax and milkpowder was derived. Secondly, compared with the migration model with distribution coefficientusing experimental data and experience value. Because distribution coefficients of paper materialwas great variation, the Fick’s migration model for paper material was more successful withdistribution coefficient using experimental data. At last, compared with the experimental data ofmigration, the predicted value of Fick’s migration model was slightly higer due to itsassumptions for full migration and the worst-case of migration, so it provided a higher safetythreshold for risk assessment of food safety.Weibull distribution theory was introduced to the field of migration because of its simpleparameter and wide applicability, and the relationship among parameters of Weibull distribution, physical properties of migrant and conditions of migration was established. The scale parameterof the Weibull distribution was found that it had a Arrhenius relationship with temperature, and itwas related to the saturated vapor pressure and vaporization enthalpy of phthalates. There is noobvious regularity between shape parameter of the Weibull distribution and temperature ormigrant, and it made a little influence on the prediction of model as a constant. Compared withthe experimental data of migration and the predicted value of Fick’s migration model, Weibullmodel can also describe similar migration curve, and it reflected the migration process morefactually even though it sometimes underestimated the value of migration.