Differentiating and grouping of oltrepo’ pavese environments according to grape maturation

Grapevine (Vitis spp.) is greatly influenced by climatic conditions and its economic value is therefore directly linked to environmental factors. Among these factors, temperature plays a critical role in vine phenology and fruit composition. In such conditions, elucidating the mechanisms employed by the vine to cope with heat waves becomes urgent. For the past few years, our research team has been producing molecular and metabolic data to highlight the molecular players involved in the response of the vine and the fruit to high temperatures [1]. Some of these temperature-sensitive genes are currently undergoing characterization using transgenesis approaches coupled or not with genome editing, taking advantage of the Microvine genotype [2].

Deficit irrigation is a viticultural practice often applied to improve the phenolic composition of red grapes and wines. However, the impact of this practice on grape terpenes – key aromatics for several grapes and wines – remains largely unknown. This study investigated the impact of deficit irrigation strategies on free and glycosylated terpenes in Gewürztraminer grapes. In a field study conducted in Oliver, BC, in 2016, 2017, and 2018, deficit irrigation regimes were applied to Gewürztraminer vines at different developmental stages (pre-veraison = Early Deficit, ED; post-veraison = Late Deficit, LD; throughout the season = Prolonged Deficit, PD). A well-irrigated control (CN) treatment was also established.

Grape phenolic content is an important quality factor that influences the appearance and mouthfeel of premium red wines.

Red wine ageing impacts its chemical and sensory characteristics such as colour, astringency and aromas evolution. Wine ageing involves many chemicals and physico-chemical reactions. Oxygen has an important role in these evolutions, especially during bottle ageing. It is known that wine composition and its antioxidant capacity are correlated to its ability to undergo with oxygen exposure [1]. A high oxygen exposure can affect wine quality by the formation of undesirable oxidative volatile compounds such as acetaldehyde [2]. Thus, ageing capacity is an important factor for wine quality and is related to extent of oxidation with ageing [3].

Grape composition is of high interest for producing quality wines. For that, grape analyses are necessary, and they still require sample preparation, whether with classical analyses or with NIR analyses.