IR and Raman Spectroscopy – Advanced and Versatile Techniques for Agrifood Quality and Authenticity Assessment

Abstract

The most important characteristics of IR versus Raman spectroscopy, their uses, according to recent literature data, are reviewed here. These advanced analytical methods are non-destructive and versatile, useful to identify plant biomarkers (metabolomics) and for agrifood quality and authenticity assessment.To give some relevant examples, we present here recent experimental data for edible oils and fruit juices FTIR fingerprints, trying to identify directly the relevant IR markers of their authenticity. Raman spectroscopy is needed to follow as complementary measurement. Both these methods are useful to fingerprint non-destructively different samples (powders, extracts, emulsions) without any preliminary processing, there are rapid and cheaper than chromatography. As complementary tools, IR and Raman spectroscopy can give added-value information on all types of molecules found in plants and food. The sine-qua-non condition to make appropriate interpretations of FTIR-Raman fingerprint markers is a good chemometric analysis (processing of raw spectra by first and second derivatives, PLS comparisons with validated methods, such as GC and HPLC).