Does foliar fertilization with Seaweed improve the productivity and quality of ‘Merlot’ grape must?

Under oenological conditions, when yeasts grow simultaneously during alcoholic fermentation, they often do not coexist passively, and in most cases, physiological and metabolic interactions are established between them. They interact by producing unpredictable compounds and fermentation products that can affect the chemical composition of the wine and therefore alter its aromatic and sensory

The vocabulary used to describe wine aroma is commonly organized according to color, raising the question of whether they reflect the reality of olfactory perception. Previous studies have assumed this convention of color-aroma matching, and have investigated color’s influence on the perception of aroma only in dyed white wine or in red wine from particular places of origin. Here 48 white and red varietal wines from around the world were evaluated in black glasses then in clear glasses by a panel of wine experts, who gave intensity ratings for aroma attributes commonly used by wine professionals. In black glasses, aromas conventionally associated with white wine were perceived in the red wines, and vice versa.

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

This study investigates the effect of pre-fermentative addition of oenological tannins on basic physicochemical parameters, total polyphenols index (TPI), antioxidant activity (DPPH method), colour traits, and volatile organic compounds (VOCs) of white wines made from ‘Vermentino’ or ‘Erbaluce’ grapes (Vitis vinifera).

Context and purpose of the study. Epidermal Patterning Factors are a family of small peptides that are highly conserved in the plant kingdom and are involved in several physiological and developmental processes.