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

The qualitative and quantitative distribution of the phenolic compounds in red wines depends on cultivars features, on grapes maturation state, on grapes processing technology including must obtention, as well as on maceration-fermentation method (Margheri, 1981). The last two factors are responsible for the different phenolic composition of the wines produced from the same cultivar.

The cultivated area of table grapes worldwide has experienced a paramount increase over the last two decades. In this current scenario, traditional varieties are being replaced by new cultivars that prioritize a profitable and sustainable agriculture, while satisfying consumer demands. It is widely recognized that wine varieties, especially those with red berry flesh, are renowned for their high antioxidant capacity and phenolic compounds, which promote health. Recently, this topic has also gained significance in table grape breeding programs.

Industry and regulatory agencies have developed regulations to ensure authenticity and compliance with wine composition limits. However, this can be truncated by the absence of simple and robust analytical methodologies, uninfluenced by the environment, different oenological techniques and cultural practices. Genetic fingerprinting is the most powerful tool for unequivocal varietal identification; it is not affected by the environment or agronomic practices; however, its usefulness in musts and wines has been controversial and there is currently no routine certification of varietal origin based on DNA analysis.

Since 1998, the GiESCO (previously named GESCO: Groupe d’Etude des Systèmes de COnduite de la vigne) has provided the scientific community with relevant contributions to the study of terroirs. Here is a synthesis of the main terroir-related fields and the major ideas the GiESCO has developed: Basic Terroir Unit and climate, Vine Ecophysiology and microclimate – moderate drought, Vineyard heterogeneity and new technologies, Viticultural Terroir Unit and canopy management, Terroir – Territory and man.

Biofilms are sessile microbial communities whose lifestyle confers specific properties. They can be defined as a structured community of bacterial cells enclosed in a self-produced polymeric matrix and adherent to a surface and considered as a method of immobilisation. Immobilised microorganisms offer many advantages for industrial processes in the production of alcoholic beverages and specially increasing cell densities for a better management of fermentation rates.