Science Demonstration of
Why Fresh Pineapple Cannot Be Used in Jell-O
Bromelain Experiment: Container on left is Jell-O made with canned pineapple (gelatin is set). Container on right is Jell-O made with fresh pineapple (gelatin is liquid).
The effect can be achieved several ways, including:
- exposing the enzyme to high temperatures
- non-competitive inhibition, where another chemical binds to the enzyme, changing the shape of the active site
Fresh Pineapple and Jell-O™
Jell-O™ is made of gelatin, a processed version of a structural protein called collagen, found in the skin and bones of animals. Although Jell-O™ is sometimes eaten plain, fruit can also be added. When that fruit is fresh pineapple,the Jell-O™ will not solidify.
Pineapple contains the enzyme bromelain, which can digest collagen protein. Adding fresh pineapple to Jell-O™ allows the bromelain to break down the gelatin’s collagen, and the Jell-O™ will not set upon cooling.
If instead of fresh pineapple, canned is used (cooked as part of the canning process), the bromelain is denatured by the heat and cannot facilitate the breakdown of collagen. Using canned pineapple allows the gelatin to firm and set.
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Classroom Bromelain Enzyme Demo