Researchers working on a solution to vineyard smoke taint

Smoke taint is a growing threat to vineyards around the world.

Bushfires, also known as wild fires, are more and more common given the onset of global warming and smoke taint from fires can ruin a vintage in a day or two.

Now researchers from Oregon State University have developed a special spray-on coating that they believe could protect grapes from being affected by wildfire smoke, the Drinks Business website reports.

The researchers expect to have a spray coating to prevent smoke damage available in the next several years.

“Wildfire smoke is an increasing problem for wineries in the United States and around the world and right now vineyard managers really have no tools to manage the effects of the smoke,” said Elizabeth Tomasino, an associate professor of enology at Oregon State. “This coating has the potential to transform the wine industry.”

Smoke taint has been a particular issue in Oregon and other parts of the western US, where recent vintages, especially that of 2020, were ruined by smoke from fires. It has also been an issue in Europe and Australia.

A new study, which was published in the Journal of Agricultural and Food Chemistry and funded by the Oregon Department of Agriculture Specialty Crop Block Grant and the US Department of Agriculture Specialty Crop Grant, examined how compounds caused by fires can be counteracted.

A cellulose nanofibre-based coating, containing chitosan and beta-cyclodextrin, was tested for effectiveness over two years at Oregon State University’s Woodhall Vineyard and its Southern Oregon Research and Extension Centre.

The researchers found that it successfully blocked compounds such as guaicol and syringol, while capturing meta-cresol. The distinction is crucial as blocking the compounds means that they are not absorbed (whereas capturing means they are).

Yanyun Zhao, an expert on food coatings, explained: “Not having to wash it off saves time, money and water for grape growers. That is what we are aiming for.”

Importantly, the study claims that the addition of the coating had no impact on the growth or quality of the grapes, meaning that the fruit’s aromas and phenols ripened as normal.

“Growers want something they can spray on their vines to protect them so if this becomes a commercially available thing it’s going to be a big game-changer," said Alexander Levin, director of the Southern Oregon Research and Extension Centre.

A press release from the university revealed that the research team is continuing to refine the coating, and working on a cost analysis to determine the viability of it as a solution for producers to deploy in the vineyard.