Changes in white wine composition after treatment with cationic exchange resin: impact on wine oxidation after 8 years of bottle storage

Wine lees are the second most important wine by-product in terms of quantity after grape stalk and marc. During aging on lees, it is well known that wine lees yield compounds that act as antioxydant. However the chemical nature of the compounds involved in this behavior (except polyphenols and glutathione) has not yet been totally elucidated. The scarce knowledge of wine lees composition and their potential exploitation make them a promising candidate to obtain new antioxidant products to be used in winemaking. In this study, an eco-sustainable approach to obtain lees extracts exhibiting antioxidant capacity is proposed. Such extracts could be used in a global enological strategy of sulfites level reduction.

AIM: Grape flavanols are involved in wine quality markers such as in-mouth sensations and colour stability.

Viticultural potential has a complex conditioning, determined by relief,
soil, climate and lithology. Delineation of viticultural potential from vineyard areas is essential for the purpose to collect the necessary data for viticultural zoning. Using this data, we can achieve greater yield quality, which is the most important criteria in viticulture. The main purpose of this research is
characterizing of viticultural potential and zoning of homogeneous viticultural zones in Goriška Brda region by assessing the suitability of defined ecological factors.

The study of wine evolution during barrel aging is an important aspect of wine quality. Our previous works have shown that wine metabolome monitoring by

1H-NMR approaches allows determining the impact of different winemaking processes including traitements using enzymes or finning agents [1].

An undesirable note called “floral taint” has been observed in red wines by winemakers in the Niagara region caused by large volumes of frozen leaves and petioles [materials-other-than-grapes (MOG)] introduced during mechanical harvest and subsequent winemaking late in the season. The volatiles, which we hypothesized are responsible, are primarily terpenes, norisoprenoids, and specific esters in frozen leaves and petioles. The purpose of this study was to investigate the volatile compounds which may cause the floral taint problem and explore how much of them (thresholds) may lead to the problem. Also, the glycosidic precursors of some of these compounds were analyzed to see the changes happening during frost events.