Phenolic profile of Sercial and Tinta Negra Vitis vinifera L. grape skins by HPLC-DAD-ESI-MSn

► First phytochemical research on phenolic components of Sercial and Tinta Negra. ► Forty four phenolics have been identified in Sercial and Tinta Negra grape skins. ► Ten of these compounds are reported for the first time in Vitis vinifera L. grapes. ► At véraison, hydroxycinnamic acids and flavonols were the main phenolic classes. ► At maturity, hydroxycinnamic acids, flavonols and anthocyanins predominate, depending on the variety.