WRI Webinar – Pietro Previtali

This webinar series showcases the excellent science our members, affiliates and collaborators are undertaking across the agriculture, food and wine sectors. Expand your network and find new collaborators!

Everyone is welcome – webinars are generally scheduled at 11am on Thursdays, with some exceptions. Registration is required.

Pietro Previtali  – Studying the unknown, undefined, unresolved sugar:flavour nexus of grapes

ARC Training Centre for Innovative Wine Production and School of Ag, Food and Wine

Abstract:  Sugars and aroma compounds are important quality traits for wine grapes, contributing to the unique bouquet of the resulting wines. Yet, it is not fully understood whether a nexus exists between these components. It could be speculated that sugars and aroma compounds are largely (or even too) different to be even possibly related. Indeed there are tremendous differences in their concentration ranges, biosynthetic pathways and evolution during berry development, but it seems suspiciously simplistic to conclude that there is no finer regulation in response to genotype, environment or cultural practices. On top of this, changing climate conditions are putting pressure on grape ripening and affecting the final composition at harvest. The research conducted during my candidature applied different approaches to uncover aspects of the sugar:flavour nexus. Firstly, we analysed sugars and aroma compounds in single berries during development, which allowed characterization of their relationship with no interference from berry asynchronous development. The study was then scaled up to vineyard trials, where varying sugar accumulation rates were established to explore effects on the aromatic profile of grapes and resulting wines. The findings of these trials highlighted the importance of ripening rates to enhance the quality of wine grapes. Based on this observation, the effectiveness of vineyard techniques to delay ripening reported in over 50 studies were quantitatively summarised using the meta-analysis approach. Overall, this research work has improved our understanding of grape flavour and shown important aspect of relevance for the wine industry.