By Aude Watrelot—Iowa State University Extension and Outreach
Grape and wine producers in Iowa and across the Midwest have a few challenges that some more popular grape-growing regions do not. Namely, the threat of cold winters, late frost springs, and hot, humid summers, factors that can play into grape production and flavor. But, Iowa’s potential in the wine industry is as unique as the state, which is to say, there is much opportunity for quality wines to be made in Iowa.
Aude Watrelot, assistant professor of enology and extension enology specialist at Iowa State University, is in the process of studying how different factors, including winemaking and chemistry, affect our sense of taste and what can be done to improve the taste perception of Iowa wines. “I’m here to help the winemakers from Iowa and the Midwest region improve their wine quality,” said Watrelot, a native of France who started with Iowa State in August.
Watrelot earned her Ph.D. in France and completed postdoctoral research at California State, Fresno, and the University of California, Davis, where some of the most popular wines in the United States are produced. But she said that every region is unique, and she sees strong potential for Iowa wines.
For Iowa, that means embracing what the state has, and overcoming the challenges. “I think we should not compare ourselves to what we already know about wine from another region,” she said. “You can find really good wine in Iowa that is unique to this part of the country.”
Watrelot’s optimism is supported by her research, which focuses on understanding the relationships between viticultural winemaking practices, grape and wine chemical composition, molecular interaction, taste, and perception. Her current research includes a focus on how to manage the concentration and composition of polyphenols in cold-hardy grapes and wines and a focus on how grape tannins interact with salivary proteins, which influences the level of astringency (dryness) experienced when drinking red wine. Watrelot’s work was featured in a December article in the Conversation, an international news service that features articles written by researchers.
“Basically, the more tannin there is in a wine, the more astringent it will be,” she writes. “When you take a sip, the large tannin molecules interact with proteins from your saliva. They combine and form complexes, reducing the number of salivary proteins available to help lubricate your mouth. It leaves your mouth with a dry sensation, like if a snail were to lose its mucus layer, it would dry out.”
The desired “dry” mouthfeel can be a bit more challenging with Iowa grapes, because the varieties grown here must first be resistant to cold harsh winters, and hot humid summers, which results in wines with lower amounts of tannins. Watrelot is in the process of assembling her own lab, where she is researching ways to improve the finished wine quality, and also ways to evaluate wine scientifically, to be as close as possible to the human perception. In addition to her lab work, Watrelot said she is excited about the workshops and outreach opportunities available to Iowa wine producers.
A wine microbiology workshop to learn about microbiological lab techniques for winemaking will be held Jan. 8, at Iowa State. For the latest events and information, visit the Midwest Grape and Wine Industry Institute online. The website has up-to-date resources for grape and wine producers, and timely articles about the wine industry.