The Science of Satisfying Taste: An Interview with John E. Hayes and David DePasquale

by Lisa Duchene

DePasquale and Hayes (photo by Steve Williams)

(L-R) David DePasquale, John E. Hayes

LD: When you meet someone new, how do you explain the Sensory Evaluation Center?

DP: I talk about taste tests. Sure, there’s a lot more that’s done, but almost everyone has an idea of what that means. And then the questions begin: “So, can I be a taste tester?”

JH: This lab has a dual function. I’m interested in why people eat the food they do, and I study that using sensory science methods within a broader, biobehavioral framework to really understand food choice behavior. We don’t all live in the same taste world. Humans have 25 different bitter taste genes, with many variations, which influences vegetable intake. Also, some people appear to need more fat and sugar to achieve the same perceptual outcome. Does that drive them to eat more energydense diets? We think so. That’s where the health and wellness aspect of our work comes in.

LD: What do you like about being a sensory scientist?

JH: You get to interact with people. You get to do very hands-on science. You get to work with a lot of different products. We’ve done pierogi, eggs, chickens raised under different conditions, bananas stored under different conditions. . . .

DP: —fruit and vegetables processed using different cleaning techniques. Some dairy products. Some chocolate products. It’s a wide array.

LD: What does sensory evaluation have to do with flavor?

JH: We use scientific methodology to take out a lot of the biases people have when reporting what they experience in terms of flavor. There are the qualities of taste and smell, but there’s also what we call chemesthesis—all the nontaste stuff that goes on in the mouth, the astringency of red wine, the tingle of carbon dioxide, the burn of chili peppers, the cooling of menthol in cough drops and gum and toothpaste.

LD: What’s new here at the center?

JH: This is a state-of-the-art facility built in 2006, but the center dates back to 1972. I took over stewardship of the center in July 2009. This is the first time a tenure-track faculty member has been in charge of the facility. Part of my mandate is to take the existing industrial work that’s been done previously and build an academic research program on top of that. In November 2009, I brought David in as our operations manager to handle the industrial side of things because he has more than 15 years of experience in the food industry.

LD: How is this lab now part of the undergraduate and graduate academic experience?

JH: We have 12 undergraduates working here who get a lot of exposure to the routine testing. Also, we have graduate students focused on sensory aspects of food science. For example, one of my students is trying to figure out how to soften the astringency of Pennsylvania wines since cool-climate wines are typically harsh and astringent.

LD: What does the center do for the food industry?

DP: We do a variety of testing that assists the industry in the product development process, with new product launches, line extensions, and product maintenance (shelf life and quality control). The earlier sensory testing comes into the development plan—the fewer prototypes, ingredients, or processes companies have to drive forward. This saves them a lot of time and money.

JH: The other major place in which we have impact is training the next generation. There’s a massive shortage of sensory scientists right now.

John E. Hayes is director and David DePasquale is operations manager of the Sensory Evaluation Center.