Testing barrier sprays in controlled smoke tents
In a changing climate many of Victoria’s key wine-producing regions are likely to experience a higher frequency and severity of bushfires and planned burn activities, as highlighted by the impact of the recent 2019/2020 bushfires. This increases the risk of producing grapes, especially in traditionally premium wine regions such as the King Valley and the Alpine Valleys. Producers have a significant need for tools that can help them protect grapes or ameliorate smoke-affected wines to enable them to produce economically viable grapes and wine and support regional economies.
The key components of the project were to:
- produce smoke-affected grapes and wines in a controlled manner using the Department of Jobs Precincts and Regions (DJPR) controlled smoking chambers
- trial some promising novel in-vineyard barrier treatments for potential reduction in the uptake of smoke compounds, which had previously only been evaluated in a laboratory-based setting
- produce smoke-affected wines and have the wines evaluated by an Australian Wine Research Institute (AWRI) expert sensory panel
- investigate blending smoke-affected wine with non-smoke-affected wine as a practical option for the remediation of smoke taint.
The smoking trials successfully resulted in the generation of smoke-affected wines, a result which was confirmed by chemical analysis and sensory evaluation. Application of chitosan to grapes prior to smoke exposure was found to reduce the uptake of smoke molecules into the grapes. However, in this trial the wine produced from the chitosan-treated Shiraz grapes was still considered to be smoke-affected, but to a lesser extent. These wines extend the AWRI’s collection of smoke-affected wines and provide an additional resource for future remediation studies, as well as being suitable training material for viticulturists and winemakers who attend future extension events on smoke taint.