By Sara Specht
From a sweet deal to the bitter end, there’s no accounting for taste. Descriptions of flavor are littered throughout our common sayings, and there’s a good reason for that. Food and flavor sensations are a key part of the human experience, and everyone knows what “bitter” feels and tastes like.
But what happens when a scientist tries to quantify taste? What, exactly, is flavor? What makes a food taste sweet, or salty, or even cooked?
It turns out, the answer is complicated. There are about 10,000 taste buds in the human tongue, as well as texture and temperature receptors. All of those combined with smell create what we think of as flavor. It is a complex equation that involves thousands of chemical reactions in every mouthful. So while you might know what “sweet” is when you taste it, defining exactly what can cause a food to taste sweet is so complicated that scientists still struggle with the question. And food companies are very interested in the answers.
For example, what is it that makes whole grains taste bitter? Maybe more importantly, what does it take to change that bitter taste—to get more people to eat whole grain bread—without affecting the inherent health benefits? This is a question that plagues producers in the food industry, and it has framed one of the first projects for the University of Minnesota’s Flavor Research and Education Center. The only center of its kind in the U.S., the FREC is using cutting-edge technology and new analytical techniques to address current flavor challenges posed by its partners in the business community.
Photos by David Hansen
While the elements of flavor drive the food manufacturing industry, the number of research laboratories dedicated to questions about flavor and fragrance has fallen in recent decades as government research funds have focused more on issues of health and food safety. But Gary Reineccius, head of the Department of Food Science and Nutrition, saw a need in the industry for a better understanding of flavor itself and problem-solving tools to drive business units more effectively. Like how to produce the healthier foods Americans need that they will actually eat.
He brought in new associate professor and flavor researcher Devin Peterson (’97–M.S.; ’01–Ph.D., food science), and together they founded the FREC in August 2011 as a partnership between scientists in the department and businesses in the food and flavor industries. The center’s business members contribute as much as $25,000 per year, which directly funds relevant research and graduate students. The concept attracted 12 members in its first year, including giants like Nestle, Pepsico and General Mills; that number has since grown to 19.
“The interest was there to develop a platform to help them understand common problems,” says Peterson. “At the end of the day, enjoyment of food is a huge part of our lifestyle. By helping processors put the pieces of the puzzle together, they’re better able to make healthier products more acceptable and, hopefully, more consumed—which is needed to make a health impact.”
The center operates out of three world-class labs on the St. Paul campus featuring state-of-the-art analytical equipment. There, researchers take a complex system—food—and break it down to its component parts, identifying single molecules or compounds that help create a target sensation. While the topics of the FREC’s research projects are influenced by its business members’ suggestions, the ultimate decision on a project’s plan and goals comes from Peterson, and the results and findings are published and shared with everyone.
“The center is about open innovation in taking foods apart and trying to understand what flavor is,” says Peterson. “There’s no directed research for any one particular company, no proprietary information. It’s about general ideas that can benefit the industry as a whole.”
For instance, food processing companies struggle to provide more nutritious food options that can sell competitively with less health-conscious option. Although children are taught in grade school that whole grains are vital to a healthy diet, only 5 percent of Americans consume the recommended amount of whole grains, and the average person consumes less than 11 percent. At the suggestion of the center’s members, the FREC has tried to identify what molecules in whole grains, or what chemical reactions in producing whole grain bread, generate bitterness. The hope is that this information can lead to solutions that don’t rely on the conventional solution of simply adding sugar to mask the bitterness.
“People say to me, ‘this is ridiculous—you can get good artisan breads and you can make people learn to like them.’ And I agree that education and teaching behavior is important,” says Peterson. “But the point is that there are a lot of families that can’t afford artisan breads, and 95 percent of the population isn’t eating the mass-produced whole grain bread that is made for their budget. A success for us would be to provide a means for more accessible, healthier, higher-quality products for the general population.”
The most important tool in the center’s research approach is an analytical method it is pioneering, dubbed “flavoromics.” The concept was developed by Reineccius after he attended a presentation about the medical use of mass spectrometry to detect the cause of silent heart attacks. That field of study, called metabolomics, uses a big-picture approach to map every tiny molecular compound in the body that is a result of creating energy—breath, waste, circulation—and applies statistical analysis to identify cause and effect on the molecular level. That day it occurred to Reineccius that these doctors were looking at the same types of small molecules that he studied in relation to flavor and aroma.
“I thought, ‘look at these people, they’re investing billions of dollars in medicine, just for us!’” Reineccius said, laughing. “Instrument companies were developing tools. Today we collect maybe 50,000 data points to analyze per sample, but they’re developing software programs to do that for the medical fields. I’m not really interested in silent heart attacks, but I figured we could link all of these chemical components in food to aroma, to flavor. I thought we could use these tools they had created to identify the drivers of perception, the compounds in food that indicate ‘cooked’ or ‘salty’.”
Flavoromics uses the same high-throughput data collection and tools as metabolomics to separate and identify thousands of compounds in food and then statistically associate those compounds with changes in flavor perception. This research process wasn’t initially accepted by the scientific community—Reineccius’ first flavoromics paper was rejected—since it is basically the opposite approach than conventional flavor research takes. The FREC’s researchers are hoping their work will establish its usefulness.
The food industry traditionally solves flavor questions empirically, Reineccius says. When they encounter an odd flavor problem, they have no way to identify the source of the problem. They don’t know whether the good flavor disappeared at one stage of the process, or if a bad flavor appeared through processing. So food companies try empirical solutions until something works, and move on. If a processor wants to reduce sugar in its foods, it isolates sweet-tasting things, but it has no techniques to register compounds that enhance sweetness, or textures or smells that are perceived as less bitter. The goal of the flavoromics approach is to understand those complex stimuli involved in different flavor perceptions, and to map the chemical differences between them.
“The tremendous power of flavoromics is that it gives us tools to find things that we have no other way to find except serendipity,” Reineccius says. “It’s not easy or straightforward, because we’re establishing statistical correlations between compounds and sensations. It doesn’t always mean they’re related, but at least we have a tool to start narrowing it down. Serendipity’s a tough way to go about life.”
The first reports on the whole grains research have been published, and Peterson is looking forward to the next round of projects for the FREC. He says that project succeeded in telling the scientists a lot about what might be causing problems for whole grains in mass produced bread, but it didn’t give them the ability to tell industry how to improve taste without affecting health. There is still work to be done in the area, and he plans to craft a future project around filling in those gaps to make a positive impact in the business of healthy food.
“At the end of the day, understanding what we respond to, understanding our products better to make them healthier and more consumed, it’s what we should be doing,” Peterson says. “This isn’t making frankenfood. It’s just understanding the food we eat in life, and how we enhance it for the population.”