By Megan Finnerty
Features Editor

While most people would say fat tastes good, most scientists would say fat doesn't really have a taste. But a researcher at Purdue University has preliminary evidence suggesting that fat does have a taste, which could be important news for Americans with heart and weight problems.

Richard Mattes, a professor of foods and nutrition in the School of Consumer and Family Sciences, finds that when fat is placed in the mouths of human subjects and then spit out, blood fat levels rise in the subjects within about two hours and stay that way for several hours.

"If people have high levels of fat in their blood, there is an increased risk of it being deposited in blood vessels throughout the body, which can then lead to an array of medical complications such as heart attacks or strokes," Mattes said.

Mattes' work, funded by the National Institute of Health, suggests that, contrary to scientific dogma that holds that fat is perceived by its texture, the mouth has chemical detectors for fat that initiate physiological processes resulting in an increased amount of fat circulating in the blood.

Right now, scientists say that humans only detect fat as a feeling in their mouths, but not as one of the five recognized tastes — sweet, salty, bitter, sour and umami.

As of now, Mattes and his researchers do not know what causes the release of fat into the bloodstream or where it comes from; those are the next steps in his research. He said the release of fat into the bloodstream could be a type of cephalic phase response, which are the changes the body undergoes when it smells, sees, thinks about or otherwise senses food, such as increased salivation and release of gastric juices.

"If we understand the mechanism for perception of fat, we can better create a product that gives that same sensory impact without the metabolic consequences," he said.

This means fat replacers, such as Olestra, marketed as Olean, could be used to lower blood fat levels and not just calorie levels. It also means that better, more satisfying fat replacers could be created to mimic the positive biological responses of eating fat, but not the negative ones.

Beverly Tepper, a professor of food science at Rutgers University in New Jersey, said Mattes has demonstrated a new phenomenon she thinks deserves further research and consideration.

"The idea that you can put fat in your mouth, chew it up and spit it out - you didn't actually ingest it, you're just tasting it - and it would have an effect on your metabolism two or so hours later, that's a pretty radical idea," she said.

Leslie Bormann, a clinical research coordinator who helped with Mattes' research, said the different types of cream cheese, which were used as the fat carrier, were identical in smell, texture and appearance.

Several tests were done to ensure that the participants couldn't distinguish between full-fat and fat-free cream cheese.

She said this suggests that participants truly tasted fat and that the rise in blood fat levels wasn't because of a psychosomatic reaction or caused by smelling, touching or seeing the fat.

Bormann said that under normal conditions, blood fat levels are affected by diet and can vary widely throughout the day, depending on the amount of fat eaten.

Eating a high-fat food normally leads to a rise of fat in the blood for about four hours. However, this research indicates that just tasting fat can lead to a more sustained elevation, lasting 6-8 hours. The fat replacers do not prevent the normal rise, but they do not stimulate the sustained rise.

"He's shown a phenomenon that's pretty different, and it's going to need more research before everyone's convinced," Tepper said. "I'm not completely convinced yet, but I think it deserves more research. I wish him luck. If this does turn out to be true, it will really change the way we think about taste and metabolism."

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Features editor:
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