IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Smoke taint: Understanding and addressing the compositional consequences of grapevine exposure to smoke

Smoke taint: Understanding and addressing the compositional consequences of grapevine exposure to smoke


Climate change has become a major challenge for grape and wine production around the world. Grapegrowers and winemakers are not only affected by increasing temperatures and prolonged drought, but by vineyard exposure to bushfire/wildfire smoke, which can taint grapes and wine, causing significant revenue losses where unpalatable smoky, ashy characters render wine unsaleable. Considerable research has therefore been undertaken over the past ~20 years to understand the compositional and sensory consequences of grapevine exposure to smoke. 

Early studies measured guaiacol and 4-methylguaiacol as markers of smoke taint, because these compounds were oak volatiles (deriving from the thermal degradation of lignin during the toasting process of cooperage) known to impart smoke-related sensory attributes, and analytical methods existed for their quantitation in wine. Today, a suite of volatile phenols (guaiacols, cresols and syringols) are measured as smoke taint marker compounds – in both free and glycosylated forms.

Volatile phenols have been identified as constituents of smoke, and can be found in grapes immediately after smoke exposure, but are rapidly glycosylated, giving volatile phenol glucosides, gentiobiosides, diglycosides and rutinosides. During fermentation, some glycoconjugates are hydrolysed by yeast and/or enzymes, releasing volatile phenols into wine. However, a significant portion of the glycoconjugate pool remains after winemaking, and can contribute to the sensory perception of smoke taint due to in-mouth hydrolysis. Ideally, smoke taint risk assessments should therefore comprise determination of both volatile phenols and volatile phenol glycoconjugates, either directly (by GC-MS and LC-MS/MS, respectively) or indirectly (by GC-MS, before and after acid or enzyme hydrolysis).

The detection/evaluation of smoke taint is further complicated by the natural occurrence of some volatile phenols (and their glycoconjugates) in the fruit (and therefore wine) of some grape varieties, without smoke exposure, for example Shiraz and Petit Sirah. Research is therefore underway to establish the varietal, regional and temporal variation in naturally-occurring volatile phenol glycoconjugate concentrations, to better inform decision-making in the lead up to vintage, where vineyards are potentially impacted by smoke. 

This presentation will provide an overview of the chemistry of smoke taint, the analytical methods available for determination of smoke taint, and the latest strategies for mitigation and amelioration of smoke taint in grapes and wine. 


Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article


Professor Kerry Wilkinson¹

¹ Department of Wine Science, Waite Research Institute, The University of Adelaide, Australia

Contact the author


grapes, glycosylation, smoke taint, volatile phenols, wine


IVAS 2022 | IVES Conference Series


Related articles…

Impact of press fractioning on current and phenolic compositions of Pinot noir and Pinot meunier wines

In the Champagne’s region, a complete press cycle is a series of pressure increases (squeezes) and decreases (returns). After alcoholic fermentation, the two wines (the “cuvee” and the “tailles”) obtained from grape juice fractions exhibit strong differences for numerous characteristics. Nevertheless, there is no study of the impact of the press cycle, followed after each pressure increase (22-28 steps), on wine colour, current analyses and phenolic composition. So, the aim of this study (vintage 2020) was to investigate the composition changes of Pinot noir and Pinot meunier wines, produced from 22-28 grape juices isolated for each complete pressing cycle.

Relationships between the Fregoni bioclimatic index (IF) and wine quality

The Fregoni bioclimatic index (IF) considers the daily temperature range during the ripening month and the number of days with temperature below 10°C.

Dual mode of action of grape cane extracts against Botrytis cinerea

Crude extracts of Vitis vinifera canes represent a natural source of stilbene compounds with well characterized antifungals properties. In our trials, exogenous application of a stilbene extract (SE) obtained from grape canes on grapevine leaves reduces the necrotic lesions caused by Botrytis cinerea

Enological evaluation of the attitude of the grapevine fumin to give varietal wines

Initiatives have been ongoing in recent years to safeguard biodiversity in the oenological sector via a process of enhancement of ancient varieties, under a pressure of a market strongly oriented towards production deriving from native vines of specific geographical zones. In that sense, Aosta Valley
(Italy) has raised the need to preserve and characterize its minority vine varieties which have the potentiality to give varietal wines. Fumin represents the 7% of the production of the region with 16 hectares of vineyards and 753 hectolitres of derived wine. Due to its large phenolic potential, strong astringency and deep colour, it has long been, and is still today, assembled or blended with other varieties as occurs, for example, for the Torrette.

Effects of different soil types and soil management on greenhouse gas emissions 

Soil is important in the carbon cycle and the dynamics of greenhouse gases (CO2, CH4 and N2O). Key soil characteristics, such as organic matter content, texture, structure, pH and microbial activity, play a determining role in GHG emissions[1]. The objective of the study is to delimit different types of soil, with different soil management and to be able to verify the differences in CO2, CH4 and N2O emissions. The study was carried out in a vineyard of Bodegas Campo Viejo in Logroño (La Rioja), whose plant material is Vitis vinifera L. cv. Tempranillo.