This project aims to understand how environmental signals translate into physiological changes in grapevines that result in changes in berry composition and in turn result in expression of terroir in wines.
The importance of terroir is twofold: First, it defines the style and quality of the wine. Second, it is a fundamental tool to position our wines in international markets. While management techniques can have a significant influence on vineyard performance, there is distinct variation in Shiraz wine style within and between Australian wine regions.
Shiraz terroir will be researched across a range of scales using selected sites and five to six potential sub-regions from the Barossa Grounds program.
At a national scale, simple canopy, environmental and fruit metrics will be assessed from individual sites in more than 20 regions that produce a full bodied premium Shiraz. These will be compared to unfinished commercial wine made from these sites.
At a regional scale, samples will be taken from more than 100 sites in the Barossa Valley. Vine, fruit and wine parameters that typify particular regions will be identified and related to the environment using GIS.
At the sub-regional scale ~20-25 sites will be selected and monitored in greater detail, including the weather, key soil physicochemical properties, soil moisture, phenology and canopy growth. Fruit will be sampled for maturity, yield and small lot winemaking. Wine descriptive analysis will be performed on small lot wines and compared to commercial wine. Fruit and wine will also be analysed for compounds relating to wine quality and style, which in turn will be related to the vine, and the environmental and sensory parameters.
Management interventions will be imposed on selected sites (~ 6) to determine the potential to optimise a sites terroir.
Grapegrowers, winemakers and wine brands can use this information to maximise the expression of terroir in wine to help secure a sustainable future for the Australian wine sector.