Wildfires can harm crops even when flames aren’t nearby. One significant impact is the unpleasant taste and aroma of wine made from smoke-exposed grapes. However, researchers have found a method to reduce this smoke taint, enhancing the wine’s flavor.
Wildfires can harm crops, even if the flames are nowhere close. An unpleasant impact of this can be the distasteful flavor and odor of wine produced from grapes exposed to smoke. Researchers have reported in ACS’ Journal of Agricultural and Food Chemistry that they’ve developed a technique to reduce this smoke taint to make the wine more enjoyable.
Volatile compounds contribute significantly to the lovely scents and tastes of food and drinks, including wine. These compounds are derived from the grapes as well as from the processes of fermentation and aging. However, not all volatile compounds found in wine are pleasant; some created by bacteria or yeast can smell similar to nail polish remover, rotten eggs, burnt rubber, or onions. When grapes absorb volatile compounds from wildfires, the resulting wine may develop an undesirable smoky, ashy, or medicinal taste that degrades its quality and economic value. To tackle this issue, producers typically use various adsorbents to eliminate these unpleasant compounds from wine. However, these methods can also strip away desirable elements that enhance the drink’s color, aroma, and flavor. Consequently, Kerry Wilkinson and the research team investigated whether molecularly imprinted polymers (MIPs) could selectively remove the volatile compounds causing smoke taint.
MIPs are man-made materials that can strongly bind to specific target compounds. The researchers aimed to use these polymers to extract the smoky substances from wine without affecting the appealing and attractive components. The team placed beads made from MIPs—either inside muslin or mesh bags or allowed them to float freely in the wine—and then conducted chemical analyses, along with taste tests involving experts, the public, students, and staff to assess the outcomes. In certain instances, the MIPs were reused by rinsing to remove the smoke substances.
To enhance the sensory attributes of the wines and get rid of unwanted volatile phenols, the researchers discovered that adding MIPs to wine post-fermentation was more efficient than incorporating them during fermentation. Moreover, regenerating the MIPs typically improved the elimination of smoke-related volatile compounds. While the MIPs did also absorb some desirable compounds linked to aroma, flavor, and red wine color, the researchers concluded that this method successfully reduces the perception of smoke taint.
The authors recognize support from the Australian Government in the context of a Cooperative Research Centre Project; Wine Australia; Metabolomics South Australia, funded through Bioplatforms Australia Pty Ltd.; the National Collaborative Research Infrastructure Strategy; and the South Australian State Government. One author indicated a potential conflict of interest as an employee of amaea.