Addressing the problem
Wines made from grapes exposed to smoke during sensitive growth stages can exhibit aromas and flavours resembling smoked meat, disinfectant, leather, salami and ashtrays. Where unfavourable smoke characteristics are detected by consumers at high concentrations the wine may be unpalatable. Unsalable wines result in financial losses for producers with costs flowing on to wine brands, market presence and future sales.
Few tools and techniques are currently available to remedy the problem of smoke effect in grapes and wine, however a significant advancement has been the development of the Smoke Taint Risk calculator. Known as STAR, this was developed by researchers at the Department of Agriculture and Food and The University of Western Australia (UWA) and predicts the seasonal sensitivity of grapevines to smoke uptake and smoke flavour development in wine.
Use of the STAR calculator with other postharvest techniques, provides opportunity to effectively reduce unwanted smoke effects in grapes and wine.
The issue of smoke effect in grape and wine production is relatively recent. One of the earliest reports resulted from the Canberra bushfires of 2003. These fires cost the Alpine Valley wine industry an estimated $4 million and caused smoke damage to vineyards in north-east Victoria and south-eastern New South Wales.
The Australian Wine Research Institute (AWRI) began investigations into the nature and amelioration of smoke effect after receiving numerous enquiries from producers noticing smoke-related sensory characters in fruit, juice and wine. Since then, further significant fires have resulted in smoke damage to wine grapes.
Consequently, research investigating smoke effects on grape and wine production has increased significantly. This has focused on the effect of smoke exposure on vines and the subsequent smoke-related characteristics in grapes and wine.
Further research has investigated the impact of the smoke timing, density, duration and assimilation by grapevines.