Order Description
Purpose
The student will demonstrate and describe the action of digestive agents on two major nutrients (carbohydrates and lipids)
Materials
Timer (with a second hand)
Small glasses (something similar to a test tube if possible)
Plastic wrap
Measuring spoons – Tablespoon (tbsp.) & ½ teaspoon (tsp.)
Plain cracker (unsalted)
Water
Vegetable oil
Red food coloring
Liquid detergent (dishwashing detergent is fine as long as there are no added ingredients such as bleach or antibacterials)
Procedure
Part A: Carbohydrate Digestion
1. Prior to beginning this experiment, rinse your mouth with plain water.
2. Obtain 2 plain crackers (each small enough to place in your mouth) of the same size. Place one cracker in on your tongue (do not chew or swallow) all allow it to dissolve. Time how long it takes for you to taste sweetness. Record the time in seconds.
3. Swallow the cracker and rinse your mouth with plain water.
4. Place the other cracker in your mouth and chew it but do not swallow. Time how long it takes for you to taste sweetness. Record the time in seconds.
5. Explain the reasons for the difference in time to taste sweetness of the non-chewed cracker to chewed cracker.
Part B: Lipid Emulsification
6. Obtain a glass and add approximately 2 tbsp. of water to it. Add to this 2 tbsp. of vegetable oil. Take a picture of the mixture.
7. Place plastic wrap over the opening of the glass, hold tight and shake vigorously for 15 seconds.
8. Allow the mixture to stand for 2 minutes. Describe what happens to the oil and water. Take a picture of the mixture.
9. Add 2 – 3 drops of red food coloring. Cover with the plastic wrap and shake vigorously for 15 seconds. Allow the mixture to stand for 2 minutes. Describe what happens to the oil and water. Take a picture of the mixture.
10. Add 1/2 tsp. of liquid detergent. Allow to stand for 1 minute. Describe the oil, water and detergent. Cover with the plastic wrap and shake vigorously for 15 seconds.
11. Allow the mixture to stand for 2 minutes. Describe what has happened. Take a picture of the mixture.
12. Allow the solution to stand for 15 minutes. Describe what has happened to the solution.
Results
Answers to your experiment questions and the photos will comprise the Analysis / Data section of your lab report.Purpose ,hypothesis and conclusion of the lab
