Krstic et al. Review of smoke taint in wine 537 Review of smoke taint in wine: smoke-derived volatile phenols and their glycosidic metabolites in grapes and vines as biomarkers for smoke exposure and their role in the sensory perception of smoke taint M.P. KRSTIC1, D.L. JOHNSON2 and M.J. HERDERICH2 1 The Australian Wine Research Institute,Victorian Node, Mooroolbark, Vic. 3138, Australia; 2 The Australian Wine Research Institute, Urrbrae, SA 5064, Australia Corresponding author: Dr Mark Krstic, email
[email protected] Abstract In recent years, the exposure of vineyards and grapes to smoke from bushfires and controlled burn events has in some instances resulted in wines described as smoke tainted. Such wines are characterised by undesirable sensory characters described as smoky, burnt, ash, smoky bacon, medicinal and ashtray. This review summarises the knowledge about the composition of smoke from forest and grass fires, describes relationships between smoke exposure of vineyards and smoke taint in wine, and outlines strategies for managing and reducing the risk to producing smoke-affected wines. The sensitivity of grapes and vines at different phenological stages to the uptake of contaminants from smoke, especially smoke-derived volatile phenols, is outlined, and the pathways for entry and metabolic transformation of volatile phenols are discussed. The potential for translocation of phenolic contaminants within the grapevine and the differences in uptake of smoke contaminants of different grape cultivars are also discussed, along with preliminary work on dose/response relationships regarding concentration and duration of exposure and subsequent expression of smoke taint in wine. The chemical basis of smoke taint in wine is described, and the relationship between volatile phenols from combustion of wood/lignin and their glycosides, and sensory panel ratings of smoke attributes in affected wines is discussed.