Science Projects for Beginners

What Household Cleaners Break Down Jell-O Best?

Before you start wondering why anyone would waste his or her time comparing the effects of household cleaners on Jell-O, think about the fact that Jell-O contains gelatin, a source of protein. So what, you say?

Gelatin is a protein formed by boiling specially prepared animal skin, bones, and connective tissue. It's used in some foods, drugs, and photographic film.

Our bodies contain enzymes that help to break down the protein we eat. When you eat meat, fish, cheese, eggs, yogurt, or other foods that contain protein, these enzymes get busy, working to make the proteins small enough to be useful to your body. The enzymes reduce proteins by breaking their chemical bonds. There are different kinds of enzymes, but the ones that specifically target proteins are called proteases.

Basic Elements

Proteases are a specific type of enzyme that targets proteins. They work to break down proteins so that they're small enough for the body to use.

While our bodies contain enzymes, so do some household cleaners. Enzymes in cleaning products work to break down protein-containing stains, such as food, milk, or blood.

By using five different household cleaners (pick whichever ones you please, but try to include cleaners used in different parts of the house, such as bathroom, kitchen, laundry, and so forth) as variables and distilled water as your control, you'll be able to see which products most effectively break down protein contained in the Jell-O.

Standard Procedure

If you have a camera available, be sure to take some “before” and “after” pictures of your experiment. Take a picture just after you've added the cleaners to the Jell-O, and another one the following day. These photos will give you a great way to illustrate your experiment.

Begin your experiment by preparing a batch of Jell-O, according to package instructions. Instead of putting it into a bowl to set, however, pour the hot liquid into the sections of an ice cube tray. Be sure to get permission before you do this and ask for help if you need it.

Once the Jell-O has cooled and solidified, use a sharp knife to cut out a little hole in the middle of each section. You'll have to remove a small plug of Jell-O to make the hole.

Fill the holes in two sections of Jell-O with one cleaner. Fill two more holes with a different cleaner, and so on. Be sure to label which cleaners you put into each section, and be sure to add distilled water—your control—to two sections.

Standard Procedure

To learn more about proteins and enzymes, check out the Cool Science for Curious Kids website at www.hhmi.org/coolscience, or the Science Made Simple website at www.sciencemadesimple.com.

Allow the Jell-O and cleaners to sit undisturbed overnight, and observe them carefully the next day. This will require that you keep your experiment out of reach of your little brother—and your dog. Record your observations of all the sections, and don't forget to take a picture.

If one cleaner broke down the Jell-O much more than another, compare the ingredients of the cleaners and see if you can figure out what might have caused the difference. Try to do some reading about proteins and enzymes so you'll be able to complete your project and analyze your results.

book cover

Excerpted from The Complete Idiot's Guide to Science Fair Projects © 2003 by Nancy K. O'Leary and Susan Shelly. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

To order this book direct from the publisher, visit the Penguin USA website or call 1-800-253-6476. You can also purchase this book at Amazon.com and Barnes & Noble.