Determination Of Food Additives In Food By Ion Chromatography And Liquid Chromatography-electrospray Tandem Mass Spectrometry

In food industry, food additives are frequently used to provide the desirable appearance,to enhance the flavor and aroma, and to prolong the shelf life. But some additives have apotential risk to human health, especially if they are excessively used. Food is a compulsorypart for people’s life so its quality and safety are very important. In recent years, the topic onhow to use food additives in safety has caused people’s attention. Due to the un-regular foodprocessing methods and food market in China, producers add too many additives in food inorder to get more profits, which have been out of the national standard a lot. Some illegalproducers even replace the food additives with some harmful chemical materials. Therefore, itis necessary to determine food additives by the methods of qualitative and quantitative. Thecurrent detective method only can find one regulate additive in food, but in terms of severalanalytes and illegal additives, this method is not available. In this study, a brief and efficientsample preparation method conbined with IC and HPLC-MS/MS was established to do thequalitative and quantitative analysis. The follwing results gave a provement of this method was also adopted todetect colorants, preservatives and sweetenersin successfully in food. The main results are asfollows:1. In this research, a method was established for the determination of propanediol, xylitol,arabitol, mannitol, sorbitol and lactitol in sugar-free food by IonChromatography-electrochemical detector. The column was Amino PAC PA10, and NaOHeluent was used to isocratic elution. By optimized chromatographic condition,6targets couldbe separated perfectly within8mins. The linear range ranged from0.1to10mg/kg, the limitof detection ranged from0.0020to0.0069mg/kg, and the recoveries of the method were inthe range of93.2to102.8%. This method was proved to be quickly, highly sensitive, and easyto be pretreated. 2. A method combining solid phase extraction with high performance liquidchromatography–electrospray ionization tandem mass spectrometry was developed forsimultaneous determination of30synthetic food additives including synthetic colorants,preservatives and sweeteners in soft drinks. Useing HLB cartridge to clean-up, The cartridgeswere then rinsed with5.0mL of15%(v/v) methanol/water solution and were finally elutedwith5.0mL methanol containing0.1%(v/v) ammonia. After optimizing the ternary gradientelution, SRM (selective reaction monitoring), positive and negative ionization modesimultaneously, all targets were efficiently separated using the optimized mobile phasesystem and mass spectrometric parameters in a single run within18min. The limit ofdetection (LOD) of all analytes was0.01~20μg/kg. When this method was applied todetermination of30synthetic food additives in soft drinks, the recoveries were in the rangeof78.5%~107.4%. Accurate and reliable method for the determination of synthetic foodadditives was developed in soft drinks, and it is suitable for the confirmation of proper useand assurance of food safety.3. Real samples which bought from Beijing’s market were analyzed according to theexperimental conditions. The results were no illegal additives found, and the contents ofsynthetic food additives in all of the samples were below the critical value defined in ChineseNational Standard. There was a phenomenon that some products did not mark the additives intheir label completely.