Saturday, October 25, 2008

Enzymes and gelatin

This is a fun and easy experiment that demonstrated the properties of enzymes.

You need a fresh pineapple (canned with not work) with the skin removed, three bowls, and a box of Jello gelatin.

Crush the pineapple in a blender until you have a fairly smooth but pulpy mixture. Place one tablespoon of the pineapple into the first bowl labeled, "Fresh pineapple." Label a second bowl, "Heated pineapple" and set it aside.

Prepare the Jello as directed on the package. Pour it into the three bowls leaving a little room in the Heated Pineapple bowl (I needed a fourth bowl because mine were small.)

Cook the rest of the pineapple on the stove for 5 minutes, stirring constantly. It will boil, which is fine; just keep stirring it. When done add 1 tablespoon of the cooked pineapple to the bowl labeled, "Heated pineapple" and stir thoroughly.


Place the bowls in the refrigerator for 4 hours. What happened?

The bowl with the fresh pineapple did not harden into Jello while the bowl with the heated pineapple did. Pineapple contains an enzyme that breaks down protein, and gelatin is protein. Heating the enzyme destroys it allowing the Jello to harden.

Canned pineapple cannot be used because it is heated before it is canned.

This experiment will work with papaya as well. The enzyme in papaya is called papain and is so potent that it is the active ingredient in prescription debriding ointments. My Blue Goo Cracked Heel ointment I get at Walmart also has papain in it, but not for long. As of November 4, 2008 the FDA has banned papain from all over-the-counter products. I better stock up now and make sure I don't rub my eyes after applying it to my feet.

5 comments:

Laura said...

What a great experiment. I'll have to try this one. Thanks for the idea!

Melissal89 said...

Great experiment! Thanks for sharing.

Blessings, Melissa
www.homeschoolblogger.com/melissal89

Prince Andrew and the Queen Mum said...

interesting!!! DS is allergic to pineapple... and probably papypa (not tested..) but we may have to just try this and see.

i shoulda listened to you;) we got to the Marie Currie book- and have jut taken a nose dive on Science. Most of the books are still too text booky for me. still i think the rest look ok but need to get back in it.

hey- do you have any good 'baby books?' DS (8yo) just said today as he was marrying off Mater (from Cars) to a lady car. How do they fertilize and have a baby? do they kiss? do they touch? he tried touching my arm to get me to have a sibbling for him apparently. EEK i am NOT prepared for this!

Kris said...

Oh my, we can only imagine what our kids are imagining in that department, LOL! My boys think that we pray that God will give us a baby, which I think is a wonderful childhood thought! I have hinted to ds#1 that Mommy and Daddy have to do something to get that to happen, though I have not explained what!

I did get the second book in the Christian series Learning About Sex from Concordia Publishing House though we have not read it yet. He hasn't been asking as of late, so maybe over Advent we'll read it.

victoradebiyi said...

this is a great experiment.. we even did this in school. very interesting