All in one method for the analysis of multiclass food additives using UHPLC-MS/MS

Food additives (FAs) have been used for centuries to improve shelf-lives, appearance and taste of food products. Although they are regulated by European legislations, FAs remain a matter of controversy. Consequently, consumers behavior is changing, yearning for more additive-free foodstuffs. Moreover, given increasing global trade with countries subjected to different regulations, focusing only on authorized food additives may not be enough to guarantee food safety. To protect the consumers, national authorities have to monitor the FAs levels and also perform exposure assessments because the food market is very versatile In this context, developing an analytical method that enables simultaneous determination of authorized and non-authorized FAs from different technological classes is essential. Contrary to most reported methods, the high-throughput multi-class method developed in the present work covers a large number of additives in a single analysis. This is challenging as FAs include molecules with different physico-chemical properties that are used in a wide range of concentrations in various type of food matrices. Seventy-six additives from four different technological classes (food colors, sweeteners, preservatives and antioxidants) are covered by the method with two thirds of these compounds not authorized in Europe. A QuEChERS based extraction has been devised using acidified acetonitrile as extraction solvent, followed by a C18 and PSA dispersive solid phase extraction step. For the development of the LCMS method, ten RP-C18 UPLC columns and different mobile phases were tested. The best result was achieved with a Shim-pack GISS C18 (100x2.1 mm, 1.9 µm). Multiple reaction monitoring is used in both positive and negative ESI modes in order to achieve sensitive and targeted analyses. For each ionization mode, an elution gradient was optimized, yielding a total run time of 22 minutes for one sample. The results will show the recoveries obtained for each group of FAs associated with the limit of detection for the non-authorized compounds and the limit of quantification for the FAs. Feasibility of this approach will be illustrated with the analysis of 10 highly consumed foodstuffs from dairy products. In conclusion, the developed method offers the possibility to detect banned substances while determining