Assessing reserve nitrogen at dormancy for predicting spring nitrogen status in Chardonnay grapevines

Yeast cells possess a cell wall comprising primarily glycoproteins, mannans, and glucan polymers. Several yeast phenotypes relevant for fermentation, wine processing, and wine quality are correlated with cell wall properties. To investigate the effect of wine fermentation on cell wall composition, a study was performed using mid-infrared (MIR) spectroscopy coupled with multivariate methods (i.e., PCA and OPLS-DA). A total of 40 yeast strains were evaluated, including Saccharomyces strains (laboratory and industrial) and non-Saccharomyces species. Cells were fermented in both synthetic MS300 and Chardonnay grape must to stationery phase, processed, and scanned in the MIR spectrum.

The acquisition of wine expertise is a multi-faceted and multisensory process with implications for sensory perception, attention, memory, and language production. With the prevalence of the predictive model of brain functioning, one area of burgeoning research interest involves wine mental imagery, since the brain relies on imagined experiences to build predictions for the future. Recent evidence has shown that, for instance, those with higher imagery vividness are more susceptible to wine advertising. However, little is known about the association between mental imagery and other associated cognitive processes, such as the ability to produce words that describe such imagery. 

Favoring the formation of volatile compounds and their precursors in must and wine represent one of the principal goals during winemaking technology. In recent years, most attention has been placed on using glycosidases to enlarge the aroma profile of white wines. The effect of enzymes makes odorless glycosidically-bound precursors be converted into aromatic compounds. This paper focuses to study the influence of enzymes (pectolytic and β-glycosides) administered before alcoholic fermentation, even if most studies analyze their use in different winemaking stages. Two semi-aromatic varieties such as Fetească regală and Sauvignon blanc were chosen.

The microbial diversity during spontaneous grape must fermentation has a determinant influence on the chemical composition and sensory properties of wine. Therefore, yeast diversity is an important target to better understand wine regionality. Hence, the aim of this study was to isolate, identify, and characterize the yeast core microbiota in grape must during the early stage of lab-scale spontaneous fermentation of withered grapes to produce Amarone della Valpolicella wine (Verona, Italy).

One of the biggest challenges of agriculture today is maintaining food safety and food quality while providing ecosystem services such as biodiversity conservation, pest and disease control, ensuring water quality and supply, and climate regulation. Organic farming was shown to promote biodiversity and carbon sequestration, and is therefore seen as one possibility of environmentally friendly production. Consumers expect organically grown crops to be free from chemical pesticides and mineral fertilizers and often presume that the quality of organically grown crops is different or higher compared to conventionally grown crops. Integrated, organic, and biodynamic viticulture were compared in a replicated field trial in Geisenheim, Germany (Vitis vinifera L. cv. Riesling). Amino acid profiles in juice, grape skin flavonoids, and hydroxycinnamic acids were monitored over three consecutive seasons beginning 7 years after conversion to organic and biodynamic viticulture, respectively. In addition, parameters such as soil nutrient status, yield, vigor, canopy temperature, and water stress were monitored to draw conclusions on reasons for the observed changes. Results revealed that the different sustainable management regimes highly differed in their amino acid profiles in juice and also in their skin flavonol content, whereas differences in the flavanol and hydroxycinnamic acid content were less pronounced. It is very likely that differences in nutrient status and yield determined amino acid profiles in juice, although all three systems showed similar amounts of mineralized nitrogen in the soil. Canopy structure and temperature in the bunch zone did not differ among treatments and therefore cannot account for the observed differences in favonols. A different light exposure of the bunches in the respective systems due to differences in vigor together with differences in berry size and a different water status of the vines might rather be responsible for the increase in flavonol content under organic and biodynamic viticulture.