New C-glucosidic ellagitannin-derived spirit compounds: Identification, quantitation and sensory contribution

Temperature and yeast nutrition profoundly impact wine quality and sensory attributes by modulating yeast aroma production and release during fermentation. While temperature and nitrogen’s individual effects are well-studied, their combined influence, including nutrient type and addition timing, remains underexplored. hence, this study aimed to investigate the simultaneous effects of these factors on fermentation kinetics, aroma production and sensory profile, particularly in a Chardonnay wine production selected as a quite aromatically neutral base.

INTRODUCTION: Oenological tannins are widely used in winemaking to improve some characteristics of wines [1] being the antioxidant properties probably one of the main reasons [2]. However, commercial tannins have different botanical sources and chemical composition [3] which probably determines different antioxidant potential. There are some few references about the antioxidant properties of commercial tannins [4] but none of them have really measured the direct oxygen consumption by them. The aim of this work was to measure the kinetics of oxygen consumption by different commercial tannins in order to determine their real capacities to protect wine against oxygen. MATERIAL AND METHODS: 4 different commercial tannins were used: T1: condensed tannin from grape seeds, T2: gallotannin from chinese gallnuts, T3: ellagitannin from oak and T4: tannin from quebracho containing condensed tannins and ellagitannins.

In viticulture sector to find new tools for pest management has become an urgent necessity. Hence, grapevines cultivation has high production rate demand and to meet the intensive market request, a massive use of pesticides is often required. In addition to the environmental problems associated with large use of chemicals, there is an increasing number of consumers which are asking for

The pinking of in white wine is the turning of color from yellow to salmon hue. White wines obtained from certain grape varieties (e.g. Chardonnay, Sauvignon blanc, Riesling, Trebbiano di Lugana) showed to be susceptible to pinking [1] that has been evaluated by an assay providing the addition of hydrogen peroxide. Even if its appearance does not seem to affect the sensory properties [2], strategies are necessary for its removal. Nowadays, the treatment with polyvinylpolipirroline (PVPP) was reported to significantly decrease the pink color [3].

Context and purpose of the study. The primary fungal diseases affecting grapevines in Europe are downy mildew and powdery mildew.