Chocolate Melts in Your Hand

Big question: Why does chocolate melt in your hand and mouth but stay solid in the cupboard?

Hold a chocolate chip in your fist, chill another in a cold bowl, and find out why chocolate melts just below body heat.

What you need

• A few chocolate chips
• A small bowl chilled in the fridge
• A small plate
• A wrapped hard candy, like a mint, for holding only
• A timer
• A napkin

What to do

1. Set upWash your hands first and check every ingredient with your grown-up, because some chocolate chips contain milk or soy, or are made near peanuts and tree nuts. Pick nut-free chips. Put one chip in the cold bowl and one on the plate.
2. Make a fistHold a third chip in your closed hand for 2 minutes. Open up. Is it soft, shiny and smeary?
3. CompareNow check the chips on the plate and in the cold bowl. Are they still solid?
4. Try the candyWipe your hand, then hold the wrapped hard candy for 2 minutes. Keep it in its wrapper and out of your mouth. Did it melt? Give it back to your grown-up when you are done.
5. The mouth testPut a chip on your tongue and do not chew. Count how long it takes to melt. Then try one from the cold bowl. Which was faster?

What is happening?

Chocolate gets its melt from cocoa butter, the fat from cocoa beans. Cocoa butter stays solid in a cool room but melts at about 93 F (34 C), a little below your body temperature of about 98 F (37 C). Your hand softens it slowly, and your warm mouth melts it fast, which is why chocolate feels so smooth. Hard candy is sugar, which needs far more heat to melt.

Hard candy can make young children choke, so keep it wrapped, never put it in your mouth, and give it back to your grown-up. A few chocolate chips are plenty. Keep chocolate away from pets, because it can make them sick.

Try it

• 
  Junior Bakers

  Chocolate Chip Cookie

• 
  Little Helpers

  Strawberry Popsicles

Check yourself