The Barossa Valley - Viticulture and Winemaking
Most of the Barossa Valley producers make use of irrigation when required to supplement the region's low rainfall during the growing season. However some of the region's oldest vineyards, especially those on the western side of the valley, practice dry land farming. Increased water stress, coupled with naturally reduced yields from these old vines, tends to produce the most deeply concentrated grapes in the valley, which often go into the Barossa's most expensive and sought-after wines.
Harvest usually begins in February and may be conducted in the cooler temperatures of night to help maintain acid levels. The generally warm climate of the Barossa Valley usually means the grapes ripen easily, producing high levels of sugars and low levels of acids. Winemaking in the Barossa often utilises the process of acidification to add balance to the wine.
The high alcohol levels from the fermented sugars may be offset by various winemaking practices including reverse osmosis and adjustments to the must. Historically, winemakers in the Barossa have utilised very short maceration periods that limit the amount of time the wine spends in contact with the skins. Often the wine is racked off the skins into oak wine barrels before fermentation ends. While this means supplementary tannins may be needed, the short maceration often gives the wines a smooth feel in the mouth.
The use of oak for maturation is also a characteristic of Barossa Valley winemaking, with the French and American barrels adding subtle aromas of vanilla and coffee.