Characterization of berry softening and sugar accumulation dynamics in a slow-ripening genotype and its response to abscisic acid treatments

Selected strains of non-Saccharomyces yeasts showed a positive effect on sensory characteristics and aromatic complexity of wine. A sequential microbial culture of non-Saccharomyces and S. cerevisiae species is usually inoculated due to poorer fermentability of non-Saccharomyces species. The aim of the study was to investigate the role of non-Saccharomyces yeasts in the production of white wines. We evaluated how individual combinations of sequential inoculations of non-Saccharomyces and S. cerevisiae species affect the aromatic compounds (volatile thiols and esters) and sensory characteristics of the wines.

Nel 2009 sono stati prelevati e analizzati mediante XRF (X-ray fluorescence) campioni di suolo, in vigneti sperimentali siti nelle province di Vicenza e di Ancona. Sono stati inoltre determinati in 2 campioni di mosto e 2 di vino delle varietà Verdicchio e Refosco dal peduncolo rosso, ed in 2 di uva Refosco dal peduncolo rosso, gli elementi in traccia mediante ICP-MS (Inductively coupled plasma-mass spectrometry).

Acacia senegal gum (Asen) is an edible dried gummy exudate [1] added in young red wines to ensure their colloidal stability, precluding the precipitation of the coloring matter. Asen macromolecules, belonging to the arabinogalactan-protein (AGP) family [2], are hyperbranched, charged and amphiphilic heteropolysaccharides composed especially of sugars (92-96 %) and a small fraction of proteins (1-3 %). Asen is defined as a continuum of macromolecules that could be separated into three fractions by hydrophobic interaction chromatography (HIC) [3-4]. HIC-F1 (85-94 % of Asen), HIC-F2 (6-18 % of Asen) and HIC-F3 (1-3 % of Asen) are named and classified in that order according to their protein content, and then a growing hydrophobicity. The efficiency of Asen towards the coloring matter instability is evaluated according to an “efficacy test” that consists to determine the Asen quantity required to prevent the flocculation by calcium of a colloidal iron hexacyanoferrate solution (International Oenological Codex).

In many regions, climate change leads to an increase in air temperature combined with a reduction of rainfall, intensifying climatic demand and water deficits (WD) (Cardell et al. 2019), which in turn may negatively impact grapevine development, yield and grape composition (Santos et al. 2020). In addition, climate change may also increase disease pressure, leading to further yield and quality losses, besides increasing costs due to increased vineyard spraying (Santos et al. 2020) and reducing viticulture acceptability by consumers (Guichard et al. 2017). Adopting new resistant varieties appears as a promising long-term solution to better manage vine protection, but unfortunately little is known regarding their behavior in front of WD.

Questo simposio organizzato dall ‘Associazione nazionale Città del Vino, che mi onoro di presiedere, è per me motivo di particolare soddisfazione perché porta a compimento parte di un percorso iniziato dall’associazione da alcuni anni e che ha un obiettivo apparentemente semplice: sollecitare gli amministratori delle Città del Vino a perseguire con tenacia, tal­volta anche con la necessaria caparbietà, programmi ed interventi che abbiano al centro, sempre, la qualità della vita dei loro territori.