Impact of canopy management on thiol precursors in white grapes: a six-year field study

Grapevine is one of the world’s most important cultivated plants, domesticated from the wild vine over 11,000 years ago. The fungi associated with it are doubtless as old as the plant itself. Despite their co-evolution with the vine over the centuries, it was only with the invention of the microscope in the seventeenth century that fungi started to be recognised.

The plasticity of grapevines in response to diverse growing conditions is influenced, among other factors, by the extent to which the roots explore the soil and the ability to accumulate and retrieve water and nutrients.
Newly planted grapevines, in particular, face challenges due to limited resources. The young plant’s ability for a fast and intensive penetration of the soil is vital in periods of water scarcity. The selection of an appropriate, site-specific rootstock significantly impacts both, the quality of the fruit produced and the economic success of the wine estate.

From the beginning of the yeast autolysis process, several interesting intracellular and cell wall constituyents are released to the media providing different characteristics to the wine, being this process extensively studied in sparkling wines due to their important contribution to their properties (1-2). Yeast derived products (YDs) try to emulate the natural yeast autolysis compounds release enhancing the organoleptic characteristics of resulting wines (2-3). This study is a comprehensive evaluation of the impact of the addition of different YDs added to base wine on the chemical, physical and sensory characteristics of the resulting sparkling wines. METHODS: Chardonnay base wine was employed to carry out this study. Three experimental YDs were added at 5 and 10 g/hL to the tirage liqueur: a yeast autolysate (YA), a yeast protein extract (PE) and an inactivated dry yeast from Torulaspora delbrueckii, (TD), and two commercial specific inactivated dry yeast: OPTIMUM WHITE® (OW) and PURE-LONGEVITY®(PL). After second fermentation, measurements were carried out after 3, 6, 9 and 18 months of aging on lees. General enological parameters, proteins, polysaccharides (HPLC-DAD-RID), volatile compounds profile (GC-MS), foaming characteristics (Mosalux), and descriptive sensory analyses were carried out.

The unique characteristics of terroir play a fundamental role in shaping the identity and quality of wines, influencing the aromatic complexity of young wines and their long-term aging potential. The volatile compounds responsible for these aromas are crucial to identifying and appreciating a given wine.

The sensory properties of a wine depends on its colours, aromas and flavors. Regarding red wines, the gustatory part consists of the acid, bitter and sweet tastes