Current Understanding
Fire and smoke Impact on grapes and wine.
Tainted Grapes
The decision to NOT harvest can be valid if taint is significant. In these instances, information on other options and how best to manage your unharvested vineyard can be found here.
Tainted Wine
Understanding and management options have greatly improved in recent years, with ongoing research providing continual improvements. The below are helpful resources that offer current summaries to further your management strategies.
- This AWRI fact sheet provides a concise overview of options.
- Promising new techniques are also explored in this AWRI webinar from 2020, including use of glycosidic enzymes to release bound taint compounds which can then be tackled by remediation techniques.
Wine Victoria and the AWRI, with the support of the Victorian Government, conducted trials with fruit from the 2020 Vintage, the results from these trials can be found here
Treating smoke affected wine with activated carbon
Treating smoke affected wine with nanofiltration
Treating smoke affected wine with glycosidases
Treating smoke affected wine with untoasted oak chips
Other AWRI factsheets on remediation options can be found here
What’s Next?
Ongoing research.
AWRI’s Research
- The relationship between smoke taint and wine flavour:
This research aims to map the varying levels and composition of smoke tainted grapes and the subsequent flavour profiles as wine. Multiple samples of grapes sourced in 2020, that have known taint markers, have been fermented into finished wine and will be continually monitored over a number of years. The resulting data from this research will determine smoke taint levels in correlation with the sensory effect on the wine produced, scaling compatible markers for varietals and stylistic options. Funded by Wine Victoria’s Bushfire Technical Package of Programs, this research will allow producers to establish a contingency plan in the event of smoke taint and to prevent loss.
- Pre-screening – quick and cost effective:
The AWRI’s Commercial Services team is working on a pre-screening analysis test, using infrared and NMR spectroscopy, that would enable rapid scanning of samples to determine whether they require further analysis with GC-MS and HPLC-MS methods. By implementing this pre-screening test, which offers a quick yes or no indication of smoke taint, it significantly reduces costs and stress for the producer. During the 2020 fires, testing laboratories across the country were inundated with thousands of tests, many of which would have been quickly and cheaply resolved with this kind of pre-screening test.
- Ongoing research:
There are new developments in research regarding the management of the impact of smoke exposure in vineyards. This plan will be updated with new information as it becomes available.
CSIRO for Atmospheric Chemistry
The CSIRO’s Air Quality Forecasting Group is currently conducting studies on the effects of smoke to air quality and the consequential negative impacts to public health. In conjunction with other research agencies, the aim of these studies is to predict the presence of smoke related volatile phenols, though these findings are yet to be released.
The National AQFx prototype system is helpful in assessing smoke impacts from bushfires and planned burns.
For grape growers who seek access to real-time air quality data for their vineyards, there are relatively low-cost commercially available sensors – PurpleAir, for example, offers a monitoring system and network.
Latrobe University
Professor Ian Porter and his team at Latrobe University, with funding from Wine Australia, are working on an early warning system using data received from a network of remote smoke sensors.
The aim of the project is to produce a risk prediction tool that will send growers a message on their phone alerting them to the possible threat of fire and smoke. More information can be found at Wine Australia or here for the latest update on the project.
University of Adelaide
Professor Kerry Wilkonson (Adelaide University), in partnership with the AWRI, has submitted an application for an Australian Research Council (ARC) linkage grant for the project Solving smoke taint: Overcoming the impacts of vineyard exposure to smoke – a funding decision is pending.
International Organisation of Vine and Wine (OIV)
Recognising the challenges faced by wine producers in managing smoke taint, the OIV has commenced drafting a technical resolution on the treatment of wine using a membrane technology, coupled with adsorption to activated carbon or resin, to reduce the excess volatile phenols.
Issues Requiring More Work and Attention
Wine Victoria is endeavouring to offer guidance, namely providing factsheets and presenting current research, to assist producers in safe-guarding and forward planning for smoke and fire risk. Information provided is from industry-led institutions, such as the AWRI, to ensure current and accurate data. This research is ongoing and will be updated as required.
The industry needs more research on quantifiable ‘tolerance’ or acceptance levels of consumers – ‘how much is too much?’.
This is still very much a case-by-case situation, as wineries will have different tolerances to smoke levels in grapes and wine, depending on the style and price point of the product.
