Anthocyanins and flavonols berries from Vitis vinifera L. cv. Brancellao separately collected from two different positions within the cluster

Galicia (N.W. Iberian Peninsula) is a Spanish region with several old-traditional winegrowing areas. Vitis vinifera L. cv. Mencía is one of the most often used to produce quality red wines in the five Galicia Denomination of Origin. However, there are traditional cultivars such as Brancellao, which were not exploited for their potential to produce quality red wines. Dynamics of anthocyanin and flavonol accumulation were studied separately in two different positions within the cluster (tips and shoulders), during 30 days before harvest. The objective of separating berries is to assess the existence of different polyphenol quality in both positions; as a consequence, the selection and harvest of those berries with a higher content of anthocyanins and flavonols could produce red wines with different qualities. Derivatives of five anthocyanins (malvidin, peonidin, petunidin, delphinidin and cyanidin) were detected in skins at both positions within the cluster. Anthocyanin contents stabilized in the 30 days prior to harvest in the berries from the shoulders whereas they continue to increase in those from the tips. Derivatives of six flavonols (quercetin, myricetin, kaempherol, laricitrin, isorhamnetin and syringetin) were detected in skin and flesh at both positions within the cluster. Dynamics of anthocyanins (from 400 to 515 mg/kg in tips; and from 598 to 574 mg/kg in shoulders) and flavonols (from 19 to 29.3 mg/kg in tips; and from 22.7 to 29.4 mg/kg in shoulders) over ripening confirmed that these polyphenols presented upward trends. Therefore, it is not necessary to harvest Brancellao berries separately and a high quality red wine will be obtained with berries from entire clusters regarding these compounds.