Researcher Pietro Previtali collecting sample Cabernet Sauvignon grapes for the study.
Original Published Date: 
Monday, July 19, 2021

Full article issued by The University of Adelaide.

A new study by ARC-supported researchers from The University of Adelaide has found it is possible to increase the flavour potential of Cabernet Sauvignon grapes by slowing down the ripening process with strategies including crop load manipulation and irrigation management.

Although earlier research has found techniques such as thinning vines and intense irrigation late in the growing season can change wine composition, the new study examined how these techniques specifically affect the development of aroma compounds in the grapes themselves.

The researchers grew Cabernet Sauvignon wine grapes at a commercial vineyard in the San Joaquin Valley in California. The vines were either thinned, or irrigated late in the growing season, or both, with grapes collected throughout the ripening period. These were compared with grapes grown in the same block where neither technique was applied.

They found that delaying ripening slowed down sugar accumulation, which led to a decrease in green aroma compounds, unwanted in winemaking, and increased fruity aromas, colour and mouthfeel compounds, associated with red wine quality.

They also observed that the composition of grape quality traits is not dependent on a single strategy.

'Rather, groups of compounds were responsive to different factors, including crop load, irrigation, ripening rate and in some cases an interaction of these,' says lead researcher, Pietro Previtali.

The study was conducted within the ARC Training Centre for Innovative Wine Production, based at The University of Adelaide, with research partners from the Training Centre and E. & J. Gallo Winery in California.

Photo credit: 

Researcher Pietro Previtali collecting sample Cabernet Sauvignon grapes for the study. Credit: Pietro Previtali.