When yeast gets activated, things get exciting.
Learning how food works is part of the joy of cooking, and this easy activity gives kids a close-up look at the magic ingredient that makes bread rise. Yeast are tiny organisms (they’re actually distant cousins of mushrooms) that eat sugar and burp out carbon dioxide gas, which is what gives that baguette its signature light, airy texture. But these tiny creatures can also blow up balloons! This experiment will teach you how different ingredients and temperatures affect yeast.
4 squeeze bottles and labels
2 packets active dry yeast
2 tablespoons white (granulated) sugar
1 tablespoon brown sugar
1 tablespoon honey
1. Add half a packet of yeast to each squeeze bottle.
2. Add 1 tablespoon of white sugar and 1 tablespoon of warm water (about 100°) to one of the bottles. Label this bottle “white sugar + warm water.” Add 1 tablespoon of white sugar and 1 tablespoon of cold water to another bottle and label it “white sugar + cold water.” Add the brown sugar and 1 tablespoon of warm water to the third bottle and label it “brown sugar + warm water.” Add the honey and 1 tablespoon of warm water to the third bottle and label it “honey + warm water.”
3. Screw the tops on the bottles, cover the caps with your finger, and shake each bottle a few times to mix the ingredients.
4. Place a water balloon over each spout and tape it into place (so it won’t pop off).
5. Set the bottles aside and wait about 30 minutes. What happened? Do you see bubbles in any of the bottles? Have any of the balloons started to inflate? Did the yeast grow faster in warm water than in cold?
6. Set the bottles in a sink or bathtub (in case of explosions!) and wait a few more hours. What happened now? Have any of the balloons completely blown up? Which sugar does the yeast seem to like best?
This activity is a part of our monthly themed kids cooking kit, “It’s Alive!” Check out our subscription options!