Mapping plant water status to indirectly assess variability in grape flavonoids and inform selective harvest decisions

In modern viticulture, sustainability must be considered not only into the winery, but in the vineyard as well, being that with the most attentive interventions in order to protect the environment. In this context, the new “fungi resistant” varieties represent a valid option for reducing the negative environmental impact of agrochemicals used in viticulture, including those ones used in organic farming (given the copper accumulation into soils). Several application studies have demonstrated the enological validity of many resistant varieties, both in price and as a blend. Also, under the production point of view, the feasibility and economical sustainability of the new resistant varieties was verified. The aim of this work was to deepen the knowledge on the organoleptic characteristics of wines obtained from the Fleurtai and Soreli varieties and to compare them with the wine obtained from Tocai Friulano, the mother variety in the area destined for the production of the Lison Classico DOCG appellation. The purpose of the work is then to verify the possibility of introducing resistant varieties into the DOCG while maintaining the wine name of the appellation linked to the territory.

Among the different strategies used in vine growing to fight against mold diseases, it can be pointed out the hybridation of traditional grape varieties with others, presenting a genetic resistance to pathogen attack. The research in this field has been encouraged in recent years due to the increased concern about human safety and environmental pollution linked to the use of agrochemicals. This approach allows to limit the number of treatments and the type of active compounds used in vine management. The environment determines the pressure degree of the diseases on vines and the biologic response of the plant to their attack.

The winemaking industry generates a substantial amount of byproducts, including grape pomace, which is often discarded as waste. However, this seemingly useless material holds a wealth of bioactive compounds with potential health benefits. Recognizing the value of circular economy principles, this study delves into the comprehensive chemical analysis of aglianco grape pomace, aiming to transform this byproduct into a valuable resource.

Chitosan is a polysaccharide produced from the deacetylation of chitin extracted from crustaceous and fungi. In winemaking chitosan is mainly used in the clarification of grape juice and wine, stabilization of white wines, removal of metals and to prevent wine spoilage by undesired microorganisms. The addition of chitosan to model wine systems was able to retard browning, reduce levels of metallic ions (Fe and Cu) and to protect varietal thiols due to its antiradical activity1. The present experiment was planned in order to evaluate the use of chitosan as a secondary antioxidant at three different stages of Sauvignon blanc fermentation and winemaking. Sauvignon blanc juices from three different locations were obtained at a commercial winery in Marlborough, New Zealand. One lots of grapes was collected from a receival bin and pressed into juice with a water-bag press, and a further juice sample was collected from a commercial pressing operation. Chitosan (1 g/L, low molecular weight, 75 – 85% deacetylated) was added to the juice after pressing, after cold settling, after fermentation, or at all these stages. Controls without any chitosan additions were also prepared.

Previous results have shown the impact of the pH on the stability of white wine proteins. In a context of global warming that implies increases in ethanol content and pH