Pineapples and Enzymes
Objective
To understand how digestive enzymes work as well as the affects of food processing on the chemical properties of certain foods.
Difficulty
Procedure: Easy
Concept: Medium
Concept
Several foods, such as fruits, contain enzymes that are responsible for breaking down proteins. Pineapples have one of these kinds of enzymes called Bromelin. To observe the effects that Bromeline has on protein students will place fresh and frozen pineapple chunks into geltatin putting the warning on the back of the Jell-O box to the test.
Materials
- 1 box of unflavored gelatin (1L of liquid Jell-O)
- 1 fresh pineapple
- 1 can of pineapple
- 1 package of frozen pineapple
- 4 test tubes
- Rack to hold test tubes upright
- Eye Protection
Hypothesis
How will the Bromelin in the pineapple affect the gelatin when it is added? Will there be any difference between the affects of the fresh, canned, and frozen pineapples?
Procedure
- Prepare the liquid Jell-O using hot water as directed on the back of the package
- Add 3mL of liquid gelatin to each of the 4 test tubes
- Add fresh pineapple to test tube 2; canned pineapple to test tube 3, and frozen pineapple to test tube 4
- Place all for test tubes into an ice bath
- Remove all test tubes when the gelatin has set in test tube 1 (the control)
Analysis
What observations can you make about each test tube? How has the added pineapple affected the gelatin in each case? Why did it do this? What conclusions can you draw from this data about the different types of pineapple? What can you determine about the gelatin?
Extensions
Try a different fruit. Research other enzymes that are responsible for the breakdown of proteins. What other methods could you use to observe the action of these proteins?