Combined use of Lachancea thermotolerans and Schizosaccharomyces pombe in winemaking

The production of Port Wine requires the addition of grape spirit to stop the fermentation, ensuring the desired sweetness

AIM: Metabolomics in food science has been increasingly used over the last twenty years. Among the tools used for wine, qNMR has emerged as a powerful tool to discern wines based on environmental factors such as geographical origin, grape variety and vintage (Gougeon et al., 2019a).

In grape berry pedicel, xylem hydraulic conductance can be impaired by blockage deposition in the lumen of xylem elements. However, the varietal difference of the interruptions has not yet been characterized. In this preliminary work, we utilized synchrotron x-ray computed microtomography experiments performed at MOGNO beamline (LNLS – Brazil) to identify possible blockage sites in natural grape pedicel xylem. For this, we imaged dehydrated pedicel’s stem portion from the Niagara Rosada variety in three different phenological stages (Pre-veraison (PreV), veraison (V) and post-veraison (PostV). The reconstructed tridimensional images with a voxel size of 1.16 µm were segmented for the identification of xylem vessel lumens. After analysing one pedicel stem per stage, we identified 658 vessels without occlusion throughout his axial plane and 41 in which we could identify possible interruptions.

In oenology, bio-protection consists in adding bacteria, yeasts or a mixture of microorganisms on grape must before fermentation in order to reduce the use of chemical compounds such as sulphites.

The plant surface typically comprises of various epidermal cell types which synthesise and deposit a protective waxy layer known as the cuticle. The cuticle is a significant contributor to important crop traits related to drought tolerance, biotic stress, postharvest fruit quality as well as providing structural support. In this work we have investigated grape berry cuticle formation in the context of the accumulation of anti-fungal specialised metabolites and the ability of the cuticle to structurally cope with the rapid expansion of ripening berries. Metabolic QTL analysis was performed in a grapevine cross population, using chemical profiling data collected via GC-MS analysis for cuticular waxes.