Determination And Migration Regular Research Of Plasticizers In Dairy Food Contact Materials

The food contact material PVC is being widely used because of its extensive applicability.In order to improve PVC's property,it often appends some additive such as plasticizers.Owing to the non covalent bond,the plasticizer usually occurred to migrate to the food.It will be harmful to the people who ate the dairy food wrapped by the packaging material containing plasticizers long-term.Because of the low amount of the plasticizers in the food and the complex matrix of the dairy food,we need the method which is sensitive and easy to make an accurate quantify of the plasticizers.The paper set the common 17 kinds of plasticizers as the objectives to establish its frequent sensitive detect method.Research the migration of the special and commercial food contact material PVC and use to established a mathematical model to verify the model's applicability.Therefore we can evaluate the safety of the dairy food contact material PVC.The specific research results are as follows:We used the large volume injection mode named PTV combined the gas chromatography-mass spectrometry technology to detect the content of the plasticizer in food contact matrial PVC and five kinds of food stimulant volvents named three percent of acetic acid,ten,twenty,fifty and ninety-five percent of ethanol.The sample pretreatment was worked by liquid-liquid extraction and the plasticizer's content was measured by GC-MS in full ion scanning to qualitative and selected ion monitoring mode and the isotope internal standards to quantitative.The method showed a good linearity(R~2>0.990).The target objects' average recovery rates(n=6)was 87.8%~117.5%,the relative standard deviation(RSD)within 0.81%~6.63%,the limits of detection were 15 ?g/L~30 ?g/L.The method was suitable for the determination of the 17 plasticizers in the food stimulant solvent.A method was established for determination of 17 kinds of plasticizers in the typical dairy pruducts named milk by ultra performance liquid chromatography-tandem mass spectrometry.The plasticizers were extracted by acetonitrile,and purified by solid phase extraction column named OASIS Prime HLB.The analytes were obtained under multiple reaction monitoring mode and the isotope internal standards were used to quantify by calibration curves.The method showed a good linearity(R~2>0.9990)in the range of 5~2000 ?g/L for 17 plasticizers analytes with average recovery rates of 89%~119%(n=6)and the relative standard deviation(RSD)within 3.62% ~ 12.60%.The limits of quantification were between 1 ?g/kg and 14 ?g/kg.The method was simple,sensitive and accurate,and was suitable for the determination of 17 plasticizers in dairy food.Firstly,we study the migration of the special food contact material which's plasticizers' amount are large by employing the five different kinds of food stimulant solvents including acid(three percent of acetic acid),water(ten percent of ethanol),alcohol(twenty percent of ethanol),and oils(ninety-five percent of ethanol)under the four tempareture(25?,40?,70? and 100?).The test results were analyzed by the grapy and showed that five solvents were all having the migration in different degree and from the three percent of acetic acid to ninety-five percent of ethanol,the migration of the plasticizers are becoming big.In the same solvent,the migration becomes bigger with the time and temperature increased.The macromolecule plasticizers named DEHA and DEHP only become to migrate in the fifty percent and ninety-five percent of ethanol.Secondly,we choose three real food white vinegar,coca-cola and grape wine to conduct the migration experiment by using the special PVC under 25 ?.The migrate value are all smaller than the homologous food stimulant solvent when the migration is going to be balance.Finally,the migration experiments research was carried out with the commercial food packaging material by the 50 % and 95% ethanol and the real food milk.And we found that the migration amount from big to small is 95 % ethanol,milk and 50 % ethanol.We aquire two important parameters named diffusion coefficient(D)and partition coefficient(K)which decides the migration by carrying out the migration experiment with special PVC in the food stimulant solvents and real food under diffierent temperature and time by making use of the Fick's 2nd law.We find that the higher initial content of plasticizers and higher temperature is,the bigger D and smaller K are.We comparie the experiment values with the predicted values to gain the relative root mean square error and it shows a good agreement by RMSE was between 0.001 % and 5.109 %,therefore it proved that the model can predict the four plasticizers' migration very well.In the same way,the fact that the maximum migration value and D acquired from the white vinger,coca-cola and grape white are smaller than the one from the 3 % acetic ace,10 % ethanol and 20 % ethanol also can make a good prove,that is the food stimulant solvemt can instead the real food to predict the migration value of the real food.What's more,it also declares that the model we established can predict the real food's migration by using the food stimulant solvent.So we can directly use the food stimulant solvent's migration to make a date support of the migration of the real food instead of using the large amount of real food to do the migration.We use the Fick second law to prove the reliability of the commercial PVC's model on the success of the special PVC's model.We compare D,K and RMSE in the 50 % ethanol,95 %ethanol and milk and find the ones in the milk smaller than the ones in 95 % ethanol.we made an easy safety evaluation of the dairy food contact material by the result acquired by the migration experiment of the commercial food packaging material.We proved the commercial food packaging material is not very safe because of the part of the plasticizers' largest migrate amount is bigger than the stated limited migrated amount.