Anthocyanin fingerprinting for authenticity studies of bilberry (Vaccinium myrtillus L.)

The high valued bilberries of Vaccinium myrtillus L. and the products derived from this berry have been mislabelled and adulterated with substitutes such as synthetic chemical or cheaper berries. Anthocyanin profiles have been successfully used in quality control as all berries have their own typical anthocyanin profile. However, in the case of wild species, the natural variation caused by genetic and environmental differences has to be investigated in order to establish a valid anthocyanin fingerprint. This is the first study to analyse the anthocyanin (aglycone and sugar moiety) profiles of bilberries originating from ten populations from climatically diverse regions of Asian Turkey. We compare the anthocyanin profiles of Turkish bilberries with their previously studied northern European Finnish counterparts with the same optimized RP-HPLC-DAD method.The Turkish bilberries did not significantly differ from their Finnish counterparts in the aglycones, which may be considered as a consistent feature for the identification of V. myrtillus. The results also showed that the sugar moieties were grouped according to the origin. A logistic regression model based on glucoside proportions classified 96.7% of samples correctly into their geographical region of origin.This may be used as a novel discriminating criteria for distinguishing bilberries among different geographical origins. The results demonstrate a basis for a new model and provide information for quality control, label claim verification and raw material source identification of V. myrtillus and related species for industry and regulatory authorities.