Exploring the botanical composition of polyfloral and monofloral honeys through DNA metabarcoding

Honey is prone to commercial fraud. It is in the interest of producers and consumers alike that its authenticity and origin be guaranteed. To this end, conventional melissopalynological analysis could be coupled with DNA metabarcoding of the plant sources for correct botanical identification of the product. This is especially relevant for the Italian market, which produces more than 30 different types of high-quality honey. For this study, the chloroplastic trnL marker was used in DNA barcoding analysis of 111 honey samples of different origin: nonItalian (n = 9); Italian polyfloral (n = 17), and Italian monofloral (n = 85). DNA metabarcoding analysis of the 85 Italian monofloral samples identified reads matching the label declaration in 72 samples, while 13 did not match, requiring further analysis to ascertain possible mislabeled events. This approach provides a powerful tool to help the authentication of the designation of origin of honey products and to assist melissopalynological analysis.