Influence of must fining on wine pinking: relationship between electrochemical and colorimetric measurements and pinking attitude of wine

The increasing vulnerability of food systems is a pressing challenge amplified by global interconnectedness.

Volatile sulphur compounds are a group of impact odorants with low odour thresholds that can contribute both positively and negatively to wine aroma. The varietal thiols, 3MH and 3MHA, are known to contribute positive tropical aromas to white wines and are most abundant in Sauvignon Blanc wines. The group of compounds contributing negative aromas are known as reductive sulphur compounds (RSCs) as they add a reductive aroma of asparagus, cooked vegetables and rotten egg to wines. All these compounds play a part in and are a result of the sulphur pathway in the yeast cell during fermentation and therefore attempting to increase the concentration of the varietal thiols may directly influence the concentration of the RSCs. The varietal thiols and the low molecular weight RSCs are highly volatile and therefore their sensory perception can change rapidly over time.

Dans la tradition classique, les vins mousseux sont le produit d’assemblage des vins d’origine différent. La choix de la typologie du moussage (brut, extra-brut, dosage zéro, etc.) généralement est une conséquence des résultats organoleptiques atteints à la fin de le période d’affinement en bouteille.

Climate change strongly affects the wine-growing sector which increasingly requires in situ adaptation strategies aimed at preserving the sustainability of production. Investigating microclimate becomes crucial in comprehending environmental pressures on plants. The microclimatic investigation conducted in the Orvieto PDO (central Italy) allowed us to highlight the climatic dynamics occurring in the last 25 years and the frequency and intensity of abiotic stresses. Two management strategies for the canopy were identified: early defoliation (ELR) and foliar application of Basalt Flour ® (FB) compared to the ordinary management (C) of the company (bud selection and topping). The effects on plant vigour indices (LAI), resource allocation in terms of carbon stored in the above-ground organs of the vine, and the microclimate of the canopy and the berry were evaluated. In particular, microclimate was evaluated through a network of sensors connected wirelessly (Wireless Sensor Network), dedicated to collecting information on temperature and humidity in the canopy and clusters.

The evolution of wine during bottle ageing has been of great interest to ensure consistent quality over time. While the role of wine closures on the amount of oxygen is well-known [1], closures could also play other roles such as the scalping phenomenon of flavour compounds. Flavour scalping has been described as the sorption of flavour compounds by the packaging material, which could result in losses of flavour intensity. It has been reported in the literature that volatile sulphur compounds (VSC) can be scalped on wine closures depending on the type of closure (traditional and agglomerated cork, screw-cap, synthetic [2]).