Oenococcus oeni clonal diversity in the carbonic maceration winemaking

Vineyards from mild temperature, high humidity locations receive often treatments with fungicides to prevent damages produced by fungi responsible for mildium, oidium and botrytis infections. In addition, insecticides are also applied to vineyards to fight again pests, which affect directly, or indirectly (as vectors of different diseases), their productivity. A fraction of the above compounds reaches the soil of vineyards, either during application, or when released from the canopy of vines due to rain-wash-off. Thereafter, depending on soil conditions (pH, organic matter) and environmental variables (regimen of rain, slope of vineyards), they might persist in this compartment, be degraded and/or transferred to water masses, modifying the biodiversity of soils and/or affecting the quality of water reservoirs.

The context of climate crisis leads to the acceleration of technological ripening of grapes, with unsuitable loss of acidity, so various vineyard management alternatives are being considered to delay the grape ripening. The delay of the vegetative cycle towards a period of milder temperatures affects ripening, but vine behavior can vary according to the area, conduction, watering, variety, etc. A work is proposed to know the response to the green pruning of shoots, executed in fruit set and in pea size, in cv. Verdejo.

Due to climate change, the occurrence of heatwaves and drought events is increasing, with significant impact on viticulture. Common ways to adapt viticulture to a changing climate include site selection, genotype selection, irrigation management and canopy management. The latter mentioned being for instance source-sink manipulations, such as leaf removal, with the aim to delay ripening.

The wine spoilage caused by Brettanomyces bruxellensis is one of the global concerns for winemakers. Detecting the presence of B. bruxellensis using routine laboratory culture techniques becomes challenging when cells enter the viable but not culturable (VBNC) state. This study aims to investigate the impact of p-coumaric acid (a volatile phenol precursor) and micronutrients on B. bruxellensis’ culturability, viability, and volatile phenol production under sulfite stress. In red wine, exposure to a high sulfite dose (100.00 mg L-1 potassium metabisulfite) resulted in immediate cell death, followed by a recovery of culturability after two weeks.

Botrytis cinerea, a fungal pathogen commonly known as grey mold, which under specific climatic conditions can develop into a desirable form known as noble rot. In this process the fungus penetrates the grape skin, allowing water evaporation and concentration of sugars and flavors, while profoundly affects the metabolite composition of grapes, leading to the production of unique and desirable compounds in the resulting wines. The result is a unique and complex wine with a luscious sweetness, heightened aromatics, and a distinct character.