Spatially Offset Raman Spectroscopy (SORS) for sustainable Olive Oil authentication - tackling the challenges in on-site food control

While olive oil production faces many challenges and prices are strongly increasing the de-mand for non-invasive analysing methods is high. The spatially offset Raman spectroscopy (SORS) can be a potential method for a sustainable food analysis since it can penetrate dif-ferent kinds of containers while giving a good spectrum of the food of interest. In this study, we developed a SORS-based method for the authentication of olive oils. Based on a dataset of verified oils of four sample groups we developed an analysis strategy using plotting, prin-cipal component analysis as well as a classification and regression model. This analysis strategy was tested in food inspections of different companies. The results show, that our strategy was successful for on-site analysis and earned positive feedback from the involved parties. In an additional validation step, we analysed 30 online retail samples where we were able to differentiate between actual adulterated and authentic olive oil samples.