Application of organic carbon status indicators on vineyard soils: the case study of DOC Piave (Veneto region, Italy)

Amino acids are crucial nitrogen sources in yeast metabolism, influencing both biomass production and fermentation rate. The breakdown byproducts of amino acids contribute to the aroma of the wine and wine’s health benefit compounds. This study focused on the yeast’s extracellular metabolic profile of tryptophan, tyrosine, and phenylalanine belonging to the group of aromatic amino acids in experimental Maraština wines. Alcoholic fermentations were conducted on sterile grape Maraština must using seven autochthonous non-Saccharomyces yeasts in sequential fermentation with commercial Saccharomyces cerevisiae.

Acidity adjustments are key to microbial control, sensory quality and wine longevity. Acidification with cation exchange resins -in acid cycle- offers the possibility to reduce the pH by exchanging wine cations, such as potassium (K+), for hydrogen ions (H+). During the exchange process, the removal of potassium and calcium ions contributes to limiting the formation of tartrate salts, thus offering an alternative solution to conventional methods for tartrate stability. Moreover, the reduction of wine pH and the removal of metals catalyzers (e.g. iron) could positively impact the wine’s oxidative stability. Therefore, the aims of this work were (a) to optimize the ion exchange process by testing different volumes and concentrations of sulfuric acid (H2SO4) during the acid cycle, (b) evaluate the effects of the ion exchange process on the formation of tartrate salts, and (c) analyze the oxidative stability of the treated wines.

The viticulture of the Douro Delimited Region, one of the heirs of ancestral viticulture, traditionally empirical and of quality, while integrating modernity and contemporary tools, respects and has always present the principles on which it was developed.

A part, at least, of red wines fruity expression may be explained by perceptive interactions involving particularly various substituted ethyl esters and acetates present at concentration far below their olfactory threshold, specifically thanks to synergistic effects. Wine sensory perception is directly linked to the stimulation of the taster at the level of olfactory epithelium by volatiles. These compounds are liberated from the matrix to the atmosphere, and will then be smelt. From a physico-chemical point of view, these volatiles ability to be released may be evaluated by their partition coefficients, which correspond to the volatile concentration ratio between the liquid and gas phase. Our goal is, through these coefficients determination, to assess if volatile matrix composition is able to impact the volatility of some compounds, and then explain sensory perception, i.eto evaluate what is called the pre-sensorial level impact.

Precision nutrient management in viticulture can be addressed on the basis of a spatial characterization of within‐vineyard vine