Resources to help manage smoke taint concerns
An updated information list for wineries and growers concerned over possible smoke contamination, has been released by the AWRI following the heatwaves and fires that affected several wine regions last month (JAN).
AWRI Senior Oenologist Adrian Coulter indicated that the AWRI extension team was expecting an influx of calls and enquiries about smoke taint, after the heatwaves and fires in January.
Current research suggests the presence of smoke taint in fruit is governed by a number of factors including the proximity and type of fire, intensity, duration of smoke cover, prevailing wind and weather conditions.
The timing of smoke exposure to grapevines is also important; there is low sensitivity to smoke uptake in the growth period to flowering, low-to-moderate risk through to veraison, and beyond veraison through to harvest, grapevines can be highly susceptible.
Information on when grapevines are most sensitive to smoke taint and what can be done to reduce the impact during winemaking can be found here.
Information on assessing vineyard viability after a bushfire can be found at here.
‘If vineyards have been affected by smoke, then the first thing we recommend is that before wineries go to the expense of a whole pick they do a controlled micro-ferment to confirm if taint is present and at what levels’, he said.
A small-lot fermentation method for assessing the impact of smoke exposure of grapes before harvest can be found here.
‘Once the ferment is completed, wineries can do their own sensory assessments and they can also send samples to the AWRI for chemical analysis – which will give them an accurate measurement of the volatile phenols and taint precursors in the wine’, he said.
There’s also a full report on smoke uptake and taint development prepared by researchers at the Western Australian Department of Agriculture and Food. The report details research around grapevine susceptibility to smoke uptake and further investigates smoke complexity (density, duration, plume distribution, composition) and smoke taint development in grapes. It can be found on the GWRDC website here.