Effects of different vinification technologies on physico-chemical properties and antioxidant activity of 'Falanghina' and 'Bombino bianco' wines

The present research was aimed to compare the traditional white vinification with a combined cryomaceration-vinification in reductive conditions, by evaluating their effects on chemical and physical indices and on antioxidant compounds of 'Falanghina' and 'Bombino bianco', two wine grape cultivars of southern Italy. According to the results, the two cultivars showed similar behaviour in response to the same vinification protocol. The processing conditions mainly affected physico-chemical characteristics such as titratable acidity, pH, SO2, tartaric and malic acids, phenolic concentrations, and antioxidant activity. Titratable acidity decreased with cryomaceration due to the tartrate precipitation, whereas the malic acid was greatly extracted from pulps and skins. In the reductive conditions applied, the SO2 was protected by the presence of ascorbic acid; thus, the wines exhibited higher free/total SO2 ratio. Cryomaceration combined with vinification in reductive conditions allowed a greater extraction of phenolic compounds from skins and, consequently, a greater antioxidant activity compared to the traditional winemaking. This behaviour was due to both the protection exerted by the low temperatures and the solubilisation of proanthocyanidins and flavans reactive with vanillin favoured by the high free SO2 content.