Choose foods with a variety of flavors. To eliminate perceptions based on texture, blend everything in a food processor. Examples could include strawberry yogurt, chicken soup, green beans, salsa, saltwater and ketchup. Remember that some foods lose flavor if chopped up and refrigerated too far ahead of time. Label them “Sample A,” “Sample B"and so on. Obtain a blindfold or blacked-out goggles so that your subjects won’t guess ahead of time what they’re supposed to be tasting. Finally, you need some nose plugs.
Run this test on your students or encourage them to set up a table in the school cafeteria, hallway or other public area, and use other students and teachers as their test subjects. Each subject should wear the blindfold and guess what each sample is, first with the nose plugs in, then without. Let them drink some water in between to wash their mouths out. Mark each person’s accuracy on a chart. Be sure to ask about food allergies before you start.
If you carried out your experiment properly, you should find that your subjects were more accurate in their guesses when their noses were unplugged. This shows that the sense of smell does profoundly affect the sense of taste. As a variation, try holding one food under the subject’s nose while feeding him another. For instance, give him applesauce to eat while waving an onion under his nose and see how that affects his ability to tell what he’s eating.
If you want to carry out something similar to this in your class, but with less work, buy a bag of hard, fruit-flavored candies. Have your students take turns feeding each other different flavors of candies. The one tasting the candy should close her eyes and hold her nose shut while the other records the results. For the second round, leave noses open. Compile your class results together on the blackboard. While not as scientific, this will illustrate the same principles to them.