Yeast mannoprotein characterization and their effect on Oenococcus oeni and malolactic fermentation

Volatile phenols from wildfire smoke are absorbed by wine grapes, resulting in undesirable smoky and ashy sensory attributes in the affected wine.[1] Unfortunately the severity of wildfires is increasing, particularly when grapes are ripening on the vine. The unwanted flavors of the wine prompted a need for solutions to prevent the uptake of smoke compounds into wine grapes. Films using cellulose nanofibers as the coating forming matrix were developed as an innovative means to prevent smoke phenols from entering Pinot noir grapes. Different film formulations were tested by incorporating low methoxy pectin or chitosan.

The growing interest in minority grape varieties is due to their potential for adaptation to global warming and their oenological capabilities. However, the cultivation of these varieties has often been limited due to their low economic efficiency. One such example is Maturana Blanca, a recently recovered and authorized minority grape variety in the DOCa Rioja region, known for its remarkable oenological potential but low productivity. This study aimed to increase the yield of Maturana Blanca by implementing the vertical cordon training system, which allowed for a higher number of buds per plant and an increased cluster count per vine.

The quality and color stability of red wines are directly related to content and distribution of phenolic compounds. However, the climate change produces the asynchrony between the dates of technological and maturity of grapes. The crop-forcing technique (CF) restores the coupling between phenolic and technological ripeness while limits vineyard yields. Blending of wines is frequently used to equilibriate composition of wines and to increase their stability, color and quality. The aim of the present work is to study the phenolic composition and color of wine blends made with FW (wines from vines subjected to CF) and CW (wines for vines under the usual cultivation practices).

Climate emergency is going to affect the agricultural suistainability, wine grapes being probably one of the crops more sensitive to environmental constraints. In this context, mitigation strategies such as the revalorization of agricultural wastes are paramount to cope with the current challenges. The use of organic mulches has been reported to reduce soil water evaporation and improve vine water status, reduce soil erosion, and increase soil organic matter with little impact on berry quality. However, less is known about their effects on the microbiote of vineyards.

Winegrowing is still characterized by the extensive use of chemical fertilizers and plant protection products, despite strong recommendations to limit these practices. A part of these xenobiotics and metals are then found in grape juice and wine, causing a major health concern, as well as negatively affecting the fermentation process. In recent years, there has been renewed interest in non-Saccharomyces yeasts. These species have a wide phenotypic diversity, which would be exploited to broaden the aromatic palette of wines.