Winter physiology in a warmer world: Cold hardiness and deacclimation sensitivity drive variation in spring phenology

Among the factors that influence the sensory quality, style, safety, sustainability, and sense of place of a wine, the contributions of microbial biodiversity are widely becoming more recognized. Throughout winemaking, multiple biochemical reactions are performed by a myriad of different microorganisms interacting in many ways.

Climate change effects on grapevine phenology and grape primary and secondary metabolites are well described in recent literature. Increasing frequency and intensity of heat waves may be responsible for important yield losses in the future. However, the impact of this event is not so well described in literature. The present study highlights the importance of grape variety tolerance as a mitigation tool to climate change.

Ellagitannin, anthocyanin and woody volatile composition of Cabernet Sauvignon wines aged in oak barrels for 12 months was evaluated. Depending on the container where malolactic fermentation (MLF) was carried out, two wine modalities were investigated: wines with MLF carried out in stainless steel tanks and barrel-fermented wines. Three toasting methods (medium toast, MT; medium toast with watering, MTAA; noisette) were considered for ageing of each wine modality. Sensory analyses (triangle and rating tests) were also performed. Two-way ANOVA of the raw experimental data revealed that the toasting method and the container where MLF took place, as well as the interaction between both factors, have a significant influence (p < 0.05) on ellagitannin, anthocyanin and woody volatile profiles of Cabernet Sauvignon wines.

The aim of this work was to study the trapping capacity of four polyaniline polymers towards phenolic compounds in wine-like model solutions. METHODS: The model wine solution was composed of 12% (v/v) and 4 g/L of tartaric acid adjusted to pH = 3.6. A series of centrifuge tubes (15 mL) were filled with 10 mL of model solution enriched with 50 mg/L of five phenolic compounds (i.e., Gallic acid, caffeic acid, (+)-catechin, (-)-epicatechin, and rutin), and treated with different doses of PANI polymer (i.e., 0, 2, 4 and 8 g/L). After the addition of the polymer, the samples were stirred using a platform shaker at room temperature (20 ºC) for 2, 8, 16 and 24 h. All treatments included three replications.

Significant wine aroma can be formed from non-volatile precursors that are linked to sugars, including but not limited to grape-derived monoterpene and C13-norisoprenoid glycosides.