Determination Of Fluorescent Whitening Agents(FWAs) In Food Packaging Materials And Migration Kinetics Of FWAs From PE To Food Simulants

In this study,building the method that determination of seven fluorescent whitening agents(FWA 52,FWA 199,FWA 135,FWA 185,FWA 378,FWA 367 and FWA 184)in paper/PE/tea determinated by HPLC-FLD.The optimal extraction conditions of seven fluorescent whitening agents were obtained by single factor experiments as follows:the mixture solution of chloroform and acetonitrile(3:7,V:V)were extracted,supernatant cleaned by HLB cartridge was collected,the sample was separated on a Water phenyl colum using acetonitrile and 5 mmol/L ammonium acetate aqueous solution was mobile phases.Excitation wavelength was 360 nm and reflection wavelength was 440 nm.The results showed that the seven fluorescent whitening agents with a good linearity in the concentration range of 5-200μg/L,which the correlation coefficient was above 0.999.The recovery of each FWA was between 71.9%and 119.9%under three levels concentration of FWAs.The relative standard deviation(RSD)was 0.01-12.90%;the LOQ was 5μg/L.The method showed the advantages of simplicity,high recovery and good precision,and is suitable for the detection of the FWAs in food packaging materials.The migration of seven FWAs migrated into two different food simulants showed that:1)The order of seven FWAs migrated from PE to fatty food simulants(corn oil)is:FWA52>FWA 367>FWA 135>FWA 184>FWA 185>FWA 378>FWA 199.The mobility of seven fluorescence whitening agents increased with temperature increasing or with the thickness of PE decreasing.The Weibull and Crank migration models were based on migration data of seven FWAs migrated into fatty food simulants(corn oil).By comparing the two models,it was found that the Weibull model of the FWA was better than the Crank model.And the relationship between the parametersτand temperature was established,τwas positively correlated with the reciprocal of temperature(1/T),βwas negatively correlated with thickness of PE in Weibull model.2)the study of FWAs migrated from PE to water system and alcohol system food simulants is only five FWAs(FWA 52,FWA 199,FWA 184,FWA 367 and FWA 135)migrated into 95%ethanol,and the migration regularity is:FWA 52>FWA 135>FWA 367>FWA 184>FWA 199,and the mobility of each FWA increased with the temperature increasing and thickness of PE decreasing.At the same time,the Crank model is established with the migration data,and the diffusion coefficient(D_P)is positively correlated with temperature.The diffusion coefficient(D_P)is negatively correlated with thickness of PE.The partition coefficient(K_F~P)is negatively correlated with temperature.The partition coefficient(K_F~P)is positively correlated with thickness of PE.