Taste, Appetite & Eating Behaviors
Hunger might be the best appetizer, but people eat for a variety of reasons. Food provides energy and vital nutrients that keep us healthy and satisfied. Overeating represents the failure of food to satisfy, and if maintained, will lead to overweight and obesity. Food manufacturers have an important role to play in public health by providing nourishing, delicious, and satisfying foods and beverages.
Research conducted in our laboratories at the Center for Public Health Nutrition helps food producers and manufacturers identify foods and food ingredients that are delicious, nutritious, and satisfying. In addition, the research helps consumers make good decisions about the types of foods they consume and it informs the scientific community about the impact of chemical constituents on consumer feelings and behavior.
Behavioral Research Laboratory
In our behavioral research laboratory, we study the details of taste, appetite and eating behavior. In particular, we are interested in the nutritional and sensory factors that determine how people perceive food tastes and textures, how hungry or full people feel in between meals and how much people eat at mealtimes.
Examples of the types of research projects we have conducted:
- Comparing the effects of liquid versus solid foods on the appetite
- Comparing the effects of sucrose and high-fructose corn syrup on the appetite
- Comparing the sensory characteristics and consumer acceptability of different foods and beverages
- Exploring whether the addition of fiber to foods increases their satiating power
- Exploring whether the addition of glutamate to foods affects appetite
- Exploring how the glycemic index of foods affects appetite
- Exploring the perceived sensory qualities and hedonic optimum of foods and beverages varying in sodium and glutamate content
Our projects exploring taste, appetite and eating behavior use robust study designs and are double-blinded, meaning that the identities of foods and beverages being tested are not known to either the research staff or participants. Double blinding is a standard procedure for the highest quality behavioral research because it minimizes the potential for participant and experimenter bias.
Exploring the Effects of Beverages on Hunger and Satiety
This graph shows how appetite (a composite of participant ratings for hunger, fullness and desire to eat) varies over the course of the day in response to different beverages. A diet soda beverage containing the fiber Nutriose, additional caffeine, and green tea catechins (Nutriose+ in red) was compared to a diet soda beverage with minimal caffeine, no fiber and no catechins (Equal Calorie control, in green). The beverages had equal calories. A condition where no beverage was given was also tested (No beverage, purple). The beverages were presented to participants three times; in the morning with a standard breakfast, again as a snack, and alone at mid day. The data show that there were differences in appetite level across time between the two beverages. When participants did not receive a beverage, they reported a substantially higher level of appetite before the lunch meal. After eating lunch, hunger ratings fell to near zero. This evidence is useful because it shows that the fiber/catechin/caffeine combination had an effect on the reported feelings of satiety for the participants.
These types of studies are very important in helping food and beverage industries decide how best to improve their products to make them more nutritious and satisfying. They are also important to consumers, in that they can help consumers decide which foods and beverages are most helpful for controlling their appetite. Finally, these studies are extremely important to the scientific community because they provide evidence as to the chemical constituents that affect human feelings such as hunger and thirst.
Exploring the Perceived Sensory Qualities of High Sodium Foods
The graph below shows participants' taste responses to chicken broth that vary along the amount sodium and glutamate. There were 4 concentrations of sodium (.16%, .53%, .85%, and 1.7%w/w) and 3 concentrations of glutamate (calcium di-gluatamate; 0%, .17%, and .33% w/w) tested in 12 total broths. Each broth was presented in random order to participants twice with time between sampling for mouth rinsing. The data show that the optimum pleasantness for this chicken broth was .93% w/w and that with the addition of .33% w/w glutamate, this optimum could be maintained for lower sodium concentrations (down to to .54% w/w).
These types of studies are very important in helping food and beverage industries understand how they can reduce the sodium content of some high sodium foods while maintaining the palatability of those foods. They are also important to consumers, in that they can help consumers decide which foods are the most healthy and tasty. Finally, these studies are extremely important to the scientific community because they provide evidence pertaining to the many dimensions of taste and texture of commonly consumed foods.