Caratterizzazione delle produzioni vitivinicole dell’area del Barolo: Un’esperienza pluridisciplinare triennale (4)

Astringency sensation decreases slowly during the aging of red wine. Complex reactions of condensation and precipitation of wine polyphenols are involved in this phenomenon. Wine composition and conditions of aging, such as temperature and oxygen availability, strongly influence evolution of the phenol matrix. Recently, a Post-Fermentative cold Maceration (PFM) technique was tested with the aim of accelerating reactions leading to the reduction of astringency and exploiting chemical compounds not extracted from the solid parts of grapes during the previous traditional maceration phase. To this purpose, an innovative maceration system was engineered and used to perform PFM trials on marc derived from vinification of different varieties of red grapes.

Agroscope is investigating the impact of yield on nitrogen (N) partitioning in grapevine and on must composition. The mechanism of N assimilation

The aim of the present work was to investigate Sauternes wines aromas. The flavor profiles of two wines (vintages 2002 and 2003) were investigated. Key-odorants have been determined by AEDA applied to Amberlite XAD-2 resin extracts. Various complementary techniques were used to identify the compounds (pHMB extraction, chemical synthesis of non-commercial standards, co-injections on two capillary columns, odor description at the sniffing port, GC-MS and GC-PFPD).

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.

During bottle aging, many thiol compounds are involved in the expression of bouquet of great aged red wines according to the quality of the closure.1,2 Identifying thiol compounds in red wines is a challenging task due several drawbacks including, the complexity of the matrix, the low concentration of these impact compounds and the amount of wine needed.3,4
This work aims to develop a new strategy based on the functionalisation of oak wood organic extracts with H₂S, to produce new thiols, in order to mimic what can happen in red wine during bottle aging. Following this approach and through sensory analysis experiments, we demonstrated that the vanilla-like aroma of fresh oak wood was transformed into intense “meaty” nuances similar to those found in old but non oxidized red wines.