Investigation of volatile and non-volatile compounds of wines obtained from interspecific hybrids cultivated in Italy and Germany

The continuous use of pesticides in viticulture is a very significant issue in the general attempt to reduce the impact of phytochemicals in the environment. Interspecific hybrids of V. vinifera, which combine the resistant traits to fungal diseases of wild American Vitis species and the wine quality of European grapevines (V. vinifera L.), represent the most promising and suitable choice for a more sustainable viticulture. A relative large number of so-called fungus-resistant PIWI varieties (from the German word ‘pilzwiderstandsfähig’) are gaining increased attention for the production of wines. This study aimed to investigate the non-volatile and volatile composition of red and white wines obtained from a selection of interspecific hybrids grown in two experimental fields, in Italy and Germany, in vintages 2013 and 2015. Also high quality V. vinifera cultivars were considered as references. The profile of non-volatile compounds was studied using different techniques: UHPLC-MS/MS [1 2] methods to study the phenolic composition (including simple phenols, anthocyanins and tannins), AAS method to analyse the mineral content, NMR [3] and FTIR [4] analysis to investigate different parameters (sugars, acids, alcohols, fermentation products, total acid, volatile acid and total SO2). The volatile profile was studied combining GC-MS [5] and HS-GC-PFPD [6] methods. The results showed that diglucosides were found in variable amounts in red interspecific wines. Multivariate methods were applied to visualize and evaluate similarities and differences in the composition of the varieties studied. The findings of this study provide a clear picture of the chemical profile of wines from different PIWI varieties identifying the most peculiar aspects of their composition.