Grape ripening timing as a base for viticultural zoning: an agro-ecological approach

At CREA – Centro di Ricerca di Viticoltura ed Enologia, based in Velletri (RM), an experimental vineyard including 10 downy mildew resistent/tolerant grape varieties and two susceptible varieties was set up with the principal goal to evaluate the behavoir of these varieties in term of resistance to downy mildew (Plasmopara viticola). This evaluation, together to oenological studies, are necessary to register them also in Regional Register (in Lazio region). Monitoring of behavior towards Plasmopara viticulture of resistant vines were done in 2020 and 2021 at different times (phenological stages) and until harvesting, according to an international standard code BBCH a centesimal phenological scale, based on coding system.

A lot of work has been done on the impact of Botrytis on the foam of sparkling wines. This work often concerns wines produced in cool regions, where Botrytis is the dominant fungal pathogen. However, in southern countries such as Spain, in particularly hot years such as 2022, the majority fungal pathogen is sometimes Rhizopus. Like Botrytis, Rhizopus is a fungus that produces an aspartic protease.

Grapevines have traditionally been grown in semi-arid areas, but viticulture is now compromised by climate change. Therefore, it is necessary to implement environmentally friendly viticulture practices to adapt grapevines to current climatic conditions. In this context, organic mulches offer many benefits, such as reduced soil erosion and increased organic matter, soil water content and crop productivity. However, these practices must not compromise grape and wine quality. Therefore, the objective of this study was to evaluate the effect on wine physicochemical and phenolic composition and sensorial properties of different soil management practices on the vine row. Over four years, five soil treatments were examined in two different vineyards.

Anthocyanins and phenolic compounds play a crucial role in winemaking, contributing to the profile, flavor, color, texture, and stability of wine. Grape clusters, specifically Vitis vinifera L. cv. Grenache, were handpicked from a commercial vineyard sited in Tudelilla, La Rioja, Spain (42°18′ 52.26″, Long. -2°7′ 59.15″, Alt. 582 m) on five distinct dates from veraison to harvest during the 2015 season. Non-contact spectral measurements were conducted on intact grape berries using a VIS-NIR spectrometer operating in the 570 – 1000 nm spectral range under controlled laboratory conditions, positioned at a distance of 25 cm from the berries. The quantification of 16 anthocyanins and phenols in 120 grape clusters was performed using HPLC, established as the reference method for validating the spectral tool.

AIM: Pre-fermentative fining is one of the central steps of white wine production. Mainly aiming at reducing the levels of suspended solids, juice fining can also assist in reducing the content of oxidizable phenolics and therefore the susceptibility of juice to oxidation.