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IVES 9 IVES Conference Series 9 Revealing the Barossa zone sub-divisions through sensory and chemical analysis of Shiraz wine

Revealing the Barossa zone sub-divisions through sensory and chemical analysis of Shiraz wine

Abstract

The Barossa zone is arguably one of the most well-recognised wine producing regions in Australia and internationally; known mainly for the production of its distinct Shiraz wines. However, within the broad Barossa geographical delimitation, a variation in terroir can be perceived and is expressed as sensorial and chemical profile differences between wines. This study aimed to explore the sub-division classification across the Barossa region using chemical and sensory measurements. Shiraz grapes from 4 different vintages and different vineyards across the Barossa (2018, n = 69; 2019, n = 72; 2020, n = 79; 2021, n = 64) were harvested and made using a standardised small lot winemaking procedure. The analysis involved a sensory descriptive analysis with a highly trained panel and chemical measurement including basic chemistry (e.g. pH, TA, alcohol content, total SO2), phenolic composition, volatile compounds, metals, proline, and polysaccharides. The datasets were combined and analysed through an unsupervised, clustering analysis. Firstly, each vintage was considered separately to investigate any vintage to vintage variation. The datasets were then combined and analysed as a whole. The number of sub-divisions based on the measurements were identified and characterised with their sensory and chemical profile and some consistencies were seen between the vintages. Preliminary analysis of the sensory results showed that in most vintages, two major groups could be identified characterised with one group showing a fruit-forward profile and another displaying savoury and cooked vegetables characters. The exploration of distinct profiles arising from the Barossa wine producing region will provide producers with valuable information about the regional potential of their wine assisting with tools to increase their target market and reputation. This study will also provide a robust and comprehensive basis to determine the distinctive terroir characteristics which exist within the Barossa wine producing region.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Lira Souza Gonzaga1, Lukas Danner2, Keren Bindon3, John Gledhill4, Annette James1, Cassandra Collins1,7, Marcos Bonada5, Paul Petrie5,6, and Susan Bastian1,7

1School of Agriculture Food and Wine, Waite Research Institute, The University of Adelaide, Adelaide, Australia 
2CSIRO, Werribee, Australia 
3The Australian Wine Research Institute, Adelaide, Australia 
4WIC Winemaking Services, Adelaide, Australia 
5South Australian Research and Development Institute, Adelaide, Australia 
6The University of New South Wales, Sydney New South Wales, Australia 
7ARC Industrial Transformation Training Centre for Innovative Wine Production, Waite Research Institute, Adelaide, Australia 

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Keywords

regionality, clustering analysis, descriptive analysis, typicity, red wine

Tags

IVES Conference Series | Terclim 2022

Citation

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