When vineyards are exposed to wildfire smoke, the grapes may absorb compounds that ultimately affect the flavor of the wine. However, a new spray-on-grape coating could help avoid wines being described as "with a hint of a burning forest". The non-toxic, edible solution was developed by scientists at Oregon State University, who began doing so after the 2020 Pacific Northwest wildfires caused many vineyard owners in the region to abandon their crops.
The liquid contains, among other ingredients, cellulose nanofibers, chitosan and beta-cyclodextrin. Just spray the liquid on your vines and let it dry into a film. When wildfire smoke subsequently drifts over the grapes, this film prevents the compounds that cause smoke stains, known as volatile phenolic compounds, from entering the underlying fruit.
It is important to note that the compound is blocked by the film rather than being absorbed by it. This means the film does not have to be washed off when picking grapes, saving time, effort and water.
In vineyard tests carried out over two years so far, the use of the coating has been found to have no impact on grape growth and quality. Wines made from some of these grapes are currently being evaluated for flavor, aroma and other characteristics.
"Wildfire smoke is a growing problem for wineries in the United States and around the world, and right now vineyard managers don't really have any tools to manage the effects of smoke," said Elizabeth Tomasino, associate professor of enology at Oregon State University. "This coating has the potential to transform the wine industry."
A paper on the research, led by Professor Zhao Yanyun, was recently published in the Journal of Agricultural and Food Chemistry.