Wine growing regions global climate analysis

Balsamic vinegars of Modena (Italy), namely Aceto Balsamico di Modena PGI (AB PGI) and Aceto Balsamico Tradizionale di Modena PDO (ABT PDO) are among the most important geographical indication products for Italy. ABT PDO, despite its very limited production, is recognized as one of the most representative Italian artisan gastronomic products, and it is known and commercialized all around the world. The economic value of ABT PDO (“affinato” and “extra-vecchio” types, depending on the aging), prepared following a traditional way and aged for many years in a set of barrels (transferring a certain amount of vinegar from one cask to another in a decreasing “topping up” procedure) is great, when compared to AB industrially prepared with caramel. AB PGI is certainly the most widespread industrial-type vinegar in the world, deriving from low-temperature condensed grape must (or cooked must) mixed with wine vinegar, obtaining balsamic vinegars with a caramel-like taste. Depending on its economic value, ABT PDO is often object of fraud, requiring to fight counterfeit products and imitations.

Grapevine Red Blotch disease (RB) is a recently discovered disease that has become a major concern for the viticulture and winemaking industry in California, USA. The causal
agent, Grapevine Red Blotch Virus (GRBV) was identified in 2011 and its presence was confirmed in several states in the US, in Canada, and in Switzerland. It has been demonstrated that RB compromised the regulation of ripening by suppressing specific ripening events, altering the expression patterns of transcription factors and causing hormonal imbalances in Zinfandel.

Polyphenolic compounds are considered to have a major impact on the quality of red wines. Sensory impact, such as astringency and bitterness, stems directly from tannin composition. Thenceforth, quick analytical measurement of phenolic compounds appears to be a real challenge for winemaking monitoring and process control. Many methods were developed to analyzed polyphenols in wine, but they are time-consuming and require chemistry skills and equipment, not suitable for a rapid routine analysis. A reliable and rapid method to obtain this kind of measurement is Fourier Transform Infrared (FTIR) spectroscopy.

Oak wood selection and maturation are essential steps in the course of barrel fabrication. Given the existence of many factors involved in the choice of raw material and in natural seasoning of oak wood, it is very difficult to determine the real impact of seasoning and selection factors on oak wood composition. A sampling was done to study the evolution of oak wood chemical composition during four seasoning steps: non matured, 12 months, 18 months and 24 months. For this sampling, three selection factors were taken into account: age, grain type and the Polyphenolic Index measured by Oakscan®. Besides extractables
(~10%), three polymers constitute the main part of oak wood: cellulose, hemicelluloses and lignins.

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.