Leaf elemental composition in a replicated hybrid grape progeny grown in distinct climates

In recent years, the impact of climate change has been pushing agriculture toward the implementation of innovative production methods aimed at countering the negative consequences of climate change.

During cold storage, grapes undergo changes that affect their visual, mechanical, and organoleptic properties, potentially impacting quality and negatively influencing consumer acceptance. Key parameters include uniform color, crunchiness, and flesh consistency. We evaluated the influence of two distinct packaging methods on the chromatic characteristics, hardness, and pedicel detachment resistance of fourteen new seedless white and red grape varieties during cold storage. These factors are crucial for maintaining the quality of the product and extending its shelf-life. The novel grape varieties were obtained through a breeding program at CREA-VE of Turi, Southern Italy.

Red grape pomace, a waste from wine production, can be valorised by extracting polyphenols, high-added value compounds used in cosmetics or oenology. For use at an industrial level, using green extraction techniques, pomace need to be stored before being processed. The aim of this study is to test various storage conditions in order to maintain high level of polyphenols over 180 days, while keeping storage cost economically interesting. In a first step, different storage conditions (ambient temperature or cooled (4°C) temperature, anaerobic (saturation with N2) or aerobic conditions, and addition of sulphur dioxide (SO2)) were compared on small samples (1 kg) packed in plastic pockets. The quality of storage was assessed by following the optical density of the pomace extract at 280 nm (DO 280 expressed as mg/l eq gallic acid), which is an indication of the amount of remaining extractable polyphenols.

Mannoproteins are macromolecules found on the surface of yeast cells, composed of hyperbranched polysaccharide negatively charged chains by mannosyl-phosphate groups, fixed to a protein core. during the alcoholic fermentation and aging on lees, these mannoproteins are released from the yeast cell wall and become the main yeast-sourced polysaccharide in wine. due to their techno-functional properties, commercial preparations of mannoproteins can be used as additives to better assure tartaric and protein stability.

Aim: To investigate the possibility of utilising simultaneous measurements of absorbance-transmittance and fluorescence excitation-emission matrix (A-TEEM) combined with chemometrics, as a robust method that gives rapid results for classification of wines from different regions of South Australia according to their Geographical Indication (GI), and to gain insight into the effect of terroir on inter regional variation.