Summary

Allow students to sample foods with and without their sense of smell to determine how smell is connected to taste.

Materials

• Photograph of a dog known for its excellent sense of smell, such as a bloodhound, German shepherd
• 3 small opaque containers
• Lemon juice
• Vinegar
• Vanilla
• Blindfold
• Knife
• Cutting board or plate
• 5 different foods* cut into a small cube shape (approx 1 cm.), such as: cheese, apple, potato, cantaloupe, pear, watermelon, cucumber, carrot, onion, plus cups of water for each child

*Note: Make sure children are not allergic to any of the foods used in this experiment.

Related Video Clip

Dinosaur Train: Play Date with Annie (2 minutes 36 seconds)

Procedures

1. PREPARATION: Inside each of the 3 mystery containers, put one of the following substances: lemon juice, vinegar, and vanilla. Cut the fruits, vegetables and cheese into uniform cubes about 1 cm. by 1 cm., organizing each food into one of three piles – in a particular order (so that one is clearly first, second, and so on.)
2. Ask students if some animals smell things that people cannot? Children may talk about how animals such as dogs, bears, and sharks have much stronger senses of smell than we do, and can identify scents we cannot. Have students discuss how animals, such as wolves, use their strong sense of smell to survive in the wild. Help children understand that a strong sense of smell can help an animal to catch its prey (animals it wants to eat), and to escape from predators (animals that want to eat it). Use language that is age-appropriate for your specific students when discussing predator and prey.
3. Let students watch a video clip (above) in which Buddy the T. rex demonstrates his powerful sense of smell.
4. Have students close their eyes and smell each of the 3 mystery containers, one at a time and say what they think the scent is. (You might encourage them to use Buddy's favorite word "hypothesis" when giving their answer. Example… "My hypothesis is that this first container has lemon juice!")
5. Ask: Do you think your sense of smell is connected to your sense of taste? To explore the answer, they are going to do an experiment. Put a blindfold on each student (or have them close their eyes) and have them children hold their noses. Explain that you are going to put a small piece of food in their mouth that is in a cube shape. Their job is to see if they can figure out what the food is—without being able to smell it. Have children take a sip of water between each example, to clean out their mouths. Give a sample of each cubed food and ask children to make a prediction. You might give a clue that the food is a fruit, or vegetable. You can also allow students to spit out the food sample if they wish. Ask students to say aloud what food they think is in their mouths. Do not reveal the answers yet.
6. Repeat the process in Step 5, presenting the three cubed foods in the same order – but this time let students use their sense of smell (not holding their noses). Again, ask students to make their predictions of what the foods are – but do not reveal the answers.
7. Have students remove their blindfolds (or open their eyes) to reveal the answers. Discuss how our sense of smell affects our ability to taste different foods.

Extensions

1. Have students think of as many different smells as they can. They might consider things like "cookie baking in the oven" "an old garbage can" and so on. As they suggest ideas, write them down in three lists: LIKE IT, DISLIKE IT, NO STRONG FEELINGS. Ask the students to talk about how different smells can affect their moods.
2. To help students explore the connection between the sense of sight and the sense of taste, have them taste five different jelly beans with their eyes closed and see if they can tell the flavors. Older students might be interested in exploring at the library or on the Internet how candy companies that make jelly beans use chemicals to artificially create tastes of different foods.