To demonstrate how much scent affects taste, remove vision from the equation by blindfolding your participants. Have them smell and then taste various fruits and vegetables and record their answers as to what they believe they have just eaten. Flavored jelly beans and baby foods are effective in this scenario, as each sample has the same basic texture, thus eliminating any texture clues.
Color is another powerful determiner of taste. When we eat or drink something that is orange, we expect it to contain orange properties. Gather a sampling of flavored sodas and waters with food colorings completely mixed in. It is better to use club soda or seltzer water to more closely mimic the same texture of the flavored soda. If you have a blueberry-flavored soda, then be sure to include a water sample colored blue. If you have a lime soda, then include a water sampled colored similarly, and so on, based on colors that match the sodas. Also, be sure that participants do not witness the mixing of the water. Each drink sample should be offered in see-through plastic cups and not the original container. The goal here is to discover if any of the participants can identify the colored waters as not containing any flavor. In most cases, participants will say they were able to taste a specific flavor in the colored water when in reality none exists. Most participants will say that orange-colored water tasted orange because their eyesight led them to believe the flavor existed.
Touch is often overlooked as a sensory device in determining flavor. And for the visually impaired, it plays a major role. To teach about the importance of touch, blindfold participants. Introduce them to a variety of fruits and vegetables by allowing them to touch the samples. Ask them to identify what the item is and have them pick one item they would like to eat. Have them describe the flavor they expect based on how the item feels.
The moisture of saliva in our mouths plays a role in determining taste as it breaks down the enzymes in food to stimulate taste buds. But what happens if your mouth is dry? Can you distinguish between sour, sweet and salty? In this test, participants should dry their tongues with a paper towel before tasting each dry sample and answer as to whether they taste anything. Have participants rinse their mouth and dry their tongue between each sample.
The various dry samples of items, such as salt, pepper, sugar and any other dry ingredients that are being tasted, should not be labeled to avoid using the sense of sight to help determine what is being tasted.
This test also addresses the importance of scent in taste. Blindfold the participants and have them taste slices of apple and pear. Record when they identify the difference between the two. Then, without them realizing you have done so, pour vanilla extract on a cotton ball and hold it under their nose without touching their nose while they eat more samples of apples and pears. Record how many participants believe they are eating something other than an apple or pear that is flavored with vanilla.
This experiment requires blindfolding because it won't work if participants can see what is happening. Seat participants in the kitchen and begin to prepare a meal and ask them to identify the activities you are performing, such as pouring juice, cracking an egg, frying bacon, cutting grapefruit, brewing coffee and making toast. Have each participant write down what they think is being prepared for them to eat based on the sounds they hear. Compare the results at the end.