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IVES 9 IVES Conference Series 9 OENO IVAS 9 OENO IVAS 2019 9 Chemical and Biochemical reactions, including grape and wines microorganisms impact 9 Varietal differences between Shiraz and Cabernet sauvignon wines revealed by yeast metabolism

Varietal differences between Shiraz and Cabernet sauvignon wines revealed by yeast metabolism

Abstract

This study investigated if compositional differences between Shiraz and Cabernet Sauvignon grape varieties could influence the production of yeast-derived compounds. This work was based on the analysis of 40 experimental red wines made in triplicate fermentations from grapes harvested from two consecutive vintages in New South Wales (Australia). Grapes were picked at three maturity stages using berry sugar accumulation as physiological indicator, from nine commercial vineyards located in three different climatic regions (temperate, temperate-warm and warm-hot). A range of 30 yeast-derived wine volatiles including esters and alcohols were quantified by HS/SPME-GC/MS. Ammonia, amino-acids and lipids were analysed in the corresponding grapes. The juice total soluble solids (°Brix) in addition to the wine alcohol and residual sugar levels were also measured. The influence of grape maturity on wine ester composition was also variety dependent, particularly for higher alcohol acetate and ethyl ester of branched acids. This study highlights that varietal differences observed in Shiraz and Cabernet Sauvignon wines involve fermentation-derived compounds irrespective of the site (soil, climate, viticultural practices). 

DOI:

Publication date: June 23, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Guillaume Antalick, Katja Suklje, John Blackman, Campbell Meeks, Urska Vrhovsek, Alain Deloire, Leigh Schmidtke

Agricultural Institute of Slovenia 
Charles Sturt University, NWGIC 
Montpellier SupAgro 
Fondazione Edmund Mach 

Contact the author

Keywords

wine volatiles, berry maturity, yeast, metabolism

Tags

IVES Conference Series | OENO IVAS 2019

Citation

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