Using this as an exemplary case study and working within the context of the EU research infrastructure METROFOOD-RI [3], EXHM/GCSL-EIM developed, validated, and accredited a new method for the determination of acrylamide in baby food and infant formula. The method employs liquid-liquid extraction, dSPE clean-up, and quantification by LC-IDMS. Using the new method, a five-fold reduction in the limit of detection was made possible, bringing the limit of quantification to levels lower than 5 \(\upmu\)g/kg. The procedure was proved to be equivalent to 'traditional' approaches employing solid phase extraction, as it showed comparable performance in a relevant interlaboratory trial and was introduced in the 2021 EURL-PC meeting. The new method has the potential to characterize materials accurately with uncertainties that are fit for the certification of reference materials at acrylamide concentrations lower than the current benchmark levels. ## References  
* Arvanitoyannis and Dionisopoulou (2014) Arvanitoyannis, I.; Dionisopoulou, N. Acrylamide: Formation, occurrence in food products, detection methods, and legislation. _Crit. Rev. Food Sci. Nutr._**2014**, _50_, 708-733. * European Commission (2019) European Commission. Commission Implementing Regulation (EU) 2019/2093 of 29 November 2019 amending Regulation (EC) No. 333/2007 as regards the analysis of 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters, glycolidyl fatty acid esters, perchlorate and acrylamide. _Off. J. Eur. Union OJL_**2019**, _317_, 96-101. * Rychlik et al. (2018) Rychlik, M.; Zappa, G.; Anforga, L.; Bel, N.; Castanheira, I.; Donard, O.F.X. ; Kourimska, L.; Ogrinc, N.; Ocke, M.C. ; Presser, K.; et al. Ensuring food integrity by metrology and FAIR data principles. _Front. Chem._**2018**, \(6\), 49. * _17.22. Optical Spectroscopic Techniques in Detecting Fuel Adulteration_
* N. Fragkoulis 1,2,*, M. Velegrakis 1 and P. Samartzis 1
* Institute of Electronic Structure and Laser (IESL)--Foundation for Research and Technology-Hellas, (FORTH), N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece
* Department of Chemistry, University of Crete, Panepistimoupoli Vouton, 70013 Heraklion, Greece
* Correspondence: nfragkoulis@iesl.forth.gr  
Adulteration of fuels is a problem of high importance to the economy and to the environment. Spectroscopic techniques, such as FTIR, UV-NIR absorption, Raman, and others, have been used to quantify adulteration. In this contribution, we present our results from the comparison of four spectroscopic techniques (FTIR, UV absorption, NIR absorption, and fluorescence) in detecting four common types of fuel adulteration: unleaded in super unleaded gasoline, heating diesel in car diesel, marine diesel in car diesel, and lubricants in car diesel. The spectroscopic data were analyzed using multivariate statistical methods (Partial Least Squares (PLS) Regression). Fluorescence, UV, and NIR absorption exhibit R\({}^{2}\) values above 93% for car diesel adulteration with marine or heating diesel, while adulteration of super with unleaded gasoline is best quantified with fluorescence. This study demonstrates the potential of optical spectroscopy as a fast and low-cost probe of fuel adulteration.