Influence of different thermohygrometric conditions on changes in instrumental texture properties and phenolic composition during postharvest withering of Corvina winegrapes (Vitis vinifera L.).

Corvina winegrapes were postharvest withered under three controlled thermohygrometric conditions. Sampling was done at different days of withering and the mechanical properties, technological ripeness parameters, phenolic composition and anthocyanin profile were determined. Depending on the condition, skin break force and pedicel detachment force significantly decreased during the dehydration process with a maximum variation of –0.258 and –1.306 N, respectively. Instead, total flavonoids of skin and seeds, and proanthocyanidins and low weight flavanols of seeds increased with a maximum variation of +1483, +733, +1022 and +469 mg/kg, respectively. The skin hardness was confirmed as an important parameter for the dehydration kinetics.