Authentication of citrus volatiles based on carbon isotope ratios

The theme of adulteration of natural flavours is briefly discussed along with the most common analytical tools used to unveil possible frauds of Citrus essential oils. Therefore, the article focuses on the main analytical approaches used for carbon isotope ratio determination of citrus secondary metabolites. Different applications of carbon isotope ratios mass spectrometry on the major Citrus products are revised to highlight the potentialities of this tool for authenticity assessment of Citrus essential oils and flavours. A deeper discussion is given on the most recent literature produced by the authors with a further evaluation of the complex picture emerged from their results. The data are overall considered to evaluate possible correlations among the carbon isotope ratios of different Citrus secondary metabolites and to prove whether univocal assessment of the genuineness of Citrus essential oils can be performed based on this analytical approach.