Take a moment to think about your favorite fermented beverage. Be it a craft beer, a complex wine, or a tangy kombucha; Before you even take a sip, you lift the glass, inhale, and let the aroma guide your expectations. That initial sensory experience, the intricate dance of taste and smell, is not accidental. It is the result of a complex chemical symphony, and it’s the world where Dr. Katherine Thompson-Witrick, an assistant professor in the University of Florida’s Food Science and Human Nutrition department and member of the FCSI, conducts her research.
“If it doesn’t smell good, people aren’t going to consume it,” Dr. Thompson-Witrick states simply. This fundamental truth is the cornerstone of her work. Her lab focuses on deconstructing the flavor and aroma profiles of fermented products to understand what makes them appealing, what signals a problem, and how they can be intentionally manipulated. By bridging her past experience in the beverage industry with academic rigor, she designs experiments that provide practical, applicable answers for producers.
The Power of a Single Change
One of the most fascinating aspects of Dr. Thompson-Witrick’s research is demonstrating how a seemingly minor adjustment can create a dramatically different final product. She provides a compelling example from her work with Brettanomyces bruxellensis, a non-traditional yeast often considered a spoiler in most beers due to its tendency to produce compounds with “medicinal, barnyard-y” notes.
In a study, her team altered a single variable: the bicarbonate level in the brewing water. This change added stress to the yeast during fermentation. The result? A significant decrease in the production of those off-putting volatile phenols. “By altering the bicarbonate levels,” she explains, “we saw it added additional stress onto the yeast, and we saw a decrease in production in those volatile compounds.” This illustrates a key principle: the fermentation environment, down to the mineral content of water, is a powerful tool for shaping flavor.
Forging Floridian Flavor
While wine connoisseurs speak of “terroir,” or the taste of a specific place, Dr. Thompson-Witrick is exploring whether that concept can apply to other ingredients, particularly those grown in Florida’s unique climate. Projects in her lab are investigating the brewing quality of Florida-grown malts and hops, ingredients not traditionally cultivated in the state’s warm, humid environment.
The challenge is significant. Hops, for instance, are typically grown in the Pacific Northwest. In collaboration with colleagues, Dr. Thompson-Witrick has analyzed hops grown in controlled greenhouse environments in Florida to see how they differ. The ultimate question is not just whether these ingredients can be grown here, but if they develop their own unique signature. “Do we want to say, ‘Hey, these hops are made from Florida,’ and you can definitely smell the difference between a Cascade from the Pacific Northwest versus a Cascade hop grown in Florida?” she muses. This work could pave the way for a new, distinctly Floridian profile in the craft beer world.
The Next Frontier – Non-Alcoholic Beverages
Looking forward, Dr. Thompson-Witrick sees the rapidly developing non-alcoholic (NA) beverage market as the next great challenge. The difficulty, she explains, is that current methods for making NA beer and wine, such as reverse osmosis or vacuum distillation to remove ethanol, also strip out the delicate flavor and aroma compounds.
“In the process, you’re removing the flavor compounds, so you have to add them back in,” she notes. Ethanol not only contributes to a beverage’s character but also helps amplify aromatic compounds, enhancing the drinker’s sensory experience. The challenge, therefore, is to find new methods or yeast strains that can produce a complex, satisfying NA beverage from the start, without the need for dealcoholizing. This research also carries an important food safety component, as removing ethanol eliminates a natural preservative, creating new hurdles for producers to overcome. From a single yeast cell reacting to its environment to the global trend of NA products, Dr. Thompson-Witrick’s work reminds us that the drinks we enjoy are living products of science. So the next time you savor a beverage, take an extra moment to appreciate the complex chemistry in your glass; a hidden world of flavor that researchers like her work every day to understand and perfect.