Profiling of anthocyanins for the taxonomic assessment of ancient purebred V. vinifera red grape varieties.

For the purpose of a varietal assessment, the berry skin anthocyanin profiles of 11 ancient native red grape varieties, sampled within the Irpinian area (Southern Italy), were compared to those of three reference Vitis vinifera cultivars and of a Kober 5BB rootstook hybrid (Vitisberlandieri×Vitisriparia). The 3,5-O-diglucoside anthocyanins and their acylated derivatives were monitored as signature compounds of non-V. vinifera grapes, using both reversed phase-high performance liquid chromatography (RP-HPLC) and matrix assisted laser desorption ionisation-time of flight (MALDI-TOF) mass spectrometry (MS). One variety (i.e. Tenta) was demonstrated to be an interspecific hybrid cross. Three additional varieties, namely Lacrima Nera, Aglianicone and a yet-unnamed variety, were classified as "late generation hybrids" (or non-V. vinifera×V. vinifera hybrids) because of a very diluted hybrid character, that was revealed only by MS methods. Five cultivars, i.e. Aglianico Lasco, Cannella, Coda di Volpe Rossa, Mentuonico, Olivella Nera, were catalogued as purebred V. vinifera. Due to the peculiar anthocyanin profile one variety (Tuccanese) remained unassigned. The methodology is of general applicability to support the process of varietal discrimination on a molecular basis with the objective of classifying autochthonous old grapevine varieties.