Taste determines people's opinion of food. Is it something they like?
For Richard Mattes, a distinguished professor of nutrition science and director of Purdue University's Ingestive Behavior Research Center, taste is the focus of his research, and he's working on a new population study to see if fat could be the sixth taste.
Question: You study the controls of human feeding and the mechanisms and functions of taste, will you explain what that means?
Answer: At Purdue, we have the Ingestive Behavior Research Center where we look at what we eat, how we eat and how much we eat. We're interested in eating disorders, but also feeding habits. How does sensory impact that?
If you ask people if they like the fat taste, they will say, yes I like the fat taste. I like high fat ice cream. But what they are really describing there is the palpability and that creamy texture. But the fatty acid may have a taste stimulant that tells us when food is rancid – it's what makes stinky cheese stinky. So what is the balance between that pleasant palpability and that unpleasant taste that would still make people eat something?
But not everybody buys it yet that fat is a taste. If you ask people to list the tastes, they would say sweet, sour, salty and bitter – sometimes umani (savory), but not fat.
We know that people are sensitive to bitterness because many toxins are bitter so it's our way of detecting poison. If fatty acids are a taste, it would be the same thing. We know that people have a sensitivity to fatty acids, but it varies and we're trying to find out what accounts for that variability.
Q: What is the study that you are doing in Denver right now?
A: We have a partnership with the Denver Museum of Nature & Science to see if there is a possible genetic basis. We are actually an exhibit in the museum and people can choose to be part of the research study. It tests their sensitivity to fatty acids. We swab their cheek and the goal is to have whole families do it to see if the sensitivity is genetic or environmental. We want to have 3,000 participants in two years.
Environment can alter palpability, but not sensitivity. We adapt to what we are exposed to. We like what we eat, we don't eat what we don't like. The best example is milk – A person who drinks skim milk won't find whole milk palpable, and a person who drinks whole milk won't find skim milk palpable.
Q: How do museum-goers participate?
A: Normally we create a beverage, but that isn't possible in a museum setting so we have film strips similar to those breath mints strips that have fatty acids embedded in them at different strengths.
Anybody that comes in can do it, it's about a 30- to 40 minute clinical trial, and we try to make it entertaining for the kids with information and novel and fun. We're not the first clinical study to be at the museum, but the museum's focus is more on genetics. We're just the latest one. It started on Nov. 11.
Q: What would come next?
A: Labs have found that if a person holds fat in their mouth, but doesn't swallow, that can increase the triglycerides that come into the blood stream and reduce how fast they clear out, and triglycerides are a cause of cardiovascular disease.
If all it takes is a sensory signal, then we could change the frequency of eating fats and if it's genetic, we could see who is more sensitive and who isn't to see who might be at a higher risk for chronic disease. We're at the stage now were we're trying to truly find if taste is a component to fat but the implications are unknown.