Delaying grapes from ripening results in more flavoursome wine
Researchers from the 成人大片 have crunched the data on the best methods to delay grapes ripening on the vine, leading to better quality wine.
鈥淥ur research focused on three common techniques used to delay ripening in grapes - the use of antitranspirants, late pruning and late source limitation,鈥 said lead author Pietro Previtali, a PhD graduate from the 成人大片鈥檚 Department of Wine Science and Waite Research Institute and the Australian Research Council Training Centre for Innovative Wine Production.
鈥淎ntitranspirants are compounds applied to the leaves of plants to reduce transpiration.
鈥淲e found that applying antitranspirants when the grapes started to change colour caused larger ripening delays, and the ripening delay was larger when there were early and late season applications.
鈥淟ate pruning is when pruning is postponed until after the apical buds have burst.
鈥淲e found there was a larger delay in ripening when the vines were pruned later in the season, however the technique is less effective on high-yielding vines.
鈥淟ate source limitation, which removes a portion of the young leaf area that accumulates sugar during ripening, is likely to be more suitable in red grape varieties with higher sugar levels, while white grape varieties may be harvested too early for this treatment to be effective.
鈥淲e also observed larger ripening delays were achieved on high-yielding vines where sugar accumulates slower.鈥
鈥淭his research can hopefully help growers make decisions that will generate higher yields and quality wine.鈥Associate Professor Chris Ford, the 成人大片鈥檚 Department of Wine Science and Waite Research Institute
Mr Previtali鈥檚 PhD supervisor, Associate Professor Chris Ford, from the 成人大片鈥檚 Department of Wine Science and Waite Research Institute, said a number of factors can lead to higher sugar concentrations in grapes.
鈥淚ncreased levels of carbon dioxide in the atmosphere, rising global temperatures and declining rainfalls, can lead to grapes ripening faster than normal,鈥 Associate Professor Ford said.
鈥淭his results in higher levels of alcohol, throwing off the balance of the wine and diminishing the quality of the product, while growers may need to postpone harvest altogether.
鈥淭his research can hopefully help growers make decisions that will generate higher yields and quality wine.鈥
The researchers examined the results of 43 studies using statistical modelling techniques traditionally used in medical and psychological research.
The research paper has been published in , titled, 鈥淎 systematic review and meta-analysis of vineyard techniques used to delay ripening.鈥
In addition to Associate Professor Ford, co-authors on the publication are Professor Kerry Wilkinson (成人大片), Filippo Giorgini (University of Milano-Bicocca, Italy), Randall Mullen (E and J Gallo Winery, California, US) and Nick Dookozlian (E and J Gallo Winery, California, US).
Media contacts:
Pietro Previtali, PhD graduate, Department of Wine Science and Waite Research Institute, 成人大片. Phone: +1 (209) 923 3002, Email: pietro.previtali@adelaide.edu.au
Lee Gaskin, Senior Media and Communications Officer, 成人大片. Mobile: +61 (0) 415 747 075 Email: lee.gaskin@adelaide.edu.au