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    Photo of Pineapple

    Science Demonstration of 
    Enzyme Bromelain
    Why Fresh Pineapple Cannot Be Used in Jell-O


    ANAT & PHYSGENERAL BIOCELL BIOMICRO 8wkMICRO 15wkINSTRUCTORS



    Denaturing an Enzyme
    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).
    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). 
    SPO VIRTUAL CLASSROOMS
    The effect can be achieved several ways, including:

    • exposing the enzyme to high temperatures
    • changing the pH
    • 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.

    Instructor's Corner
    Page last updated: 
    1/2016
    CLASS NOTES 
    from the free STEM 
    education site 
    Science Prof Online
    Continued ...
    Classroom Bromelain Enzyme Demo
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