Study On The Detection Method Of Prohibited And Misused Flavors In Food

In recent years,the flavor of food has developed rapidly,but the problems such as the over use of flavors and the illegal addition of prohibited ingredients are still prominent problems,which cause potential harm to consumers’ health.The US Food and Drug Administration and the European Food Safety Agency(EFSA)have clearly defined the chemical composition and content of foods that can be used for food.Therefore,it is necessary to establish an analytical method for rapid detection of flavor components in foods.This paper mainly carries out the following research work:1.Gas chromatography tandem mass spectrometry(GC-MS/MS)and gas combustion isotope mass spectrometry(GC/C/IRMS)for the determination of banned aromatic compounds in coffee were established and analyzed by gas chromatography tandem mass spectrometry(GC-MS/MS).Coffee samples were extracted with ethyl acetate and purified with PSA.The detection limits(LOD)and quantification limits(LOQ)of these compounds ranged from 0.00004 to 2.0μg/kg and from 0.0002 to 8.0 μg/kg,respectively.The average recovery was 83.75%to 106.73%.N-methyl-2-carboxaldehyde(NMC)was extracted from coffee samples by simultaneous distillation and analyzed by GC/C/IRMS.The endogenous NMC of coffee beans ranged from-35.036 to-31.081,while the exogenous NMC ranged from-27.872 to-23.851.Univariate analysis of variance(ANOVA,P<0.001)showed that there were significant differences between endogenous and exogenous δ13C values of NMC.The results showed that the GC-MS/MS method was sensitive and reliable,and the sources of NMC in coffee could be distinguished by GC/C/IRMS.Finally,the method has been successfully applied to the analysis of coffee products.2.A QuEChERS-gas chromatography tandem mass spectrometry(GC-MS/MS)method was developed for the simultaneous determination of 6 banned fragrance components in tea.Tea samples were extracted with ethyl acetate and purified with C18+PSA.The linear range of compounds was 1-200 μg/L(R2>0.999).The detection limit was 0.005-1 μg/kg and the quantitative limit was 0.02-2 μg/kg.The average recovery was 82.35%-93.17%.The intra-day and inter-day precision was less than 10%.The results showed that the method was simple,cheap,reproducible and sensitive,and can be used for the detection of 6 banned fragrances in tea.3.A liquid chromatography tandem triple quadruple bar mass spectrometry(LC-MS/MS)was developed for simultaneous determination of 8 essential components in pasteurized milk.The samples were extracted by acetonitrile solvent,purified by low temperature centrifugation,scanned by ESI positive ion mode,and quantitatively analyzed by matrix standard curve.The detection limit was 0.0005-0.6 μg/kg and the quantitative limit was 0.001-2μg/kg.The average recovery rate was 85.61%-107.54%.The intra-day and inter-day precision was less than 10%.The results showed that the method has the advantages of low cost,good reproducibility and high sensitivity,and can be used for the detection of such substances in pasteurized milk samples.