Enzyme Lab

Jello Lab-Enzymes

Abstract- In this lab, my partner and I investigated why the directions for preparing jello say to not add fresh pineapple, only cooked, to jello mix. We tested frozen, fresh and canned pineapple in batches of jello, adding the fruit before the jello was put in the fridge. The fresh and frozen did not set, but the canned did, proving that not only does cooking pineapple allow one to use it in jello, it neutralizes the enzymes involved in the entire process.

Intro

Question -How does Jello’s ability to set differ with different types of pineapple?

Background- Bromelain is an enzyme which pineapple and pineapple juice contain. When entered into the digestive system, it interferes with the body’s ability to digest food. This occurs because the Bromelain contains enzymes such as protease, which break down amino acids. When added to a substance such as jello, which has a similar structure as a protein in a human body, with amino acids. A fruit such as pineapple would have this so that an animal which eats it, would not be able to digest the seeds of the fruit, and would then deposit them away from the original plant, spreading them and replanting the plant.

Hypothesis- If my partner and I prepare four petri of jello dishes exactly the same, and add canned, fresh and frozen pineapple (and one control), then the only the canned and the control will set and harden.

Methodology

Materials- 4 petri dishes, one box jello powder, warm water, cold water, beaker, mixing rod, fresh pineapple, frozen pineapple, canned pineapple

Procedure-

1. Measure out your specific amount of jello powder.
2. Add proportional amount of boiling water and mix for 3 minutes.
3. Once powder is dissolved, add same amount of cold water.
4. Add your specific amount of each type of pineapple (canned, fresh, frozen) to its specific dish.
5. Label Petri dishes and stack and put in fridge.
6. Return and observe results 3 days later.

Results

Dish #	1	2	3	4
Pineapple type	Fresh	Canned	Frozen	Control
Ammt. of pineapple	1.39g	1.39g	1.39g	-
Ammt. of jello	20mL	20mL	20mL	20mL

Conclusion- When the dishes were checked on the third day of the experiment, it was found that only dishes 2 and 4 had “gelled” jello. These results failed to reject our hypothesis. The control did what we expected and solidified, proving that there was no error when preparing the jello. The dish with the canned pineapple solidified because when pineapple is cooked, the enzymes are neutralized and therefore inactive. One possible source of error could be that my partner or I could have mixed up one of the fruits. Another possible error could be that one of us could have improperly prepared the jello, or left it out of the fridge.