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The Accidental Scientist: Science of Cooking Exploratorium
Candy Bread Eggs Pickles Meat Seasoning

activity: Smell the Maillard Reaction!
Cook amino acids and sugar and discover the range of aromas released!

Kids, please don't try this at home without the help of an adult. The corn syrup can get very hot, very quickly.
What Do I Need? .
pure corn syrup Did You Know?
The Maillard reaction, also known as the browning reaction, is what makes self-tanning products work.
amino acid caplets (available at health-food stores)
a nonstick skillet
a teaspoon
oven mitts or hot pads
What Do I Do?


1. Put about a teaspoon of corn syrup in the nonstick skillet.



2. Open one of the amino acid caplets and smell the powder inside. Does it have a distinctive odor?

3. Pour the amino acid powder into the corn syrup in the skillet.

4. Turn the heat to high.

5. Move the skillet back and forth to better disperse the powder as the corn syrup/amino acid mixture heats up and liquefies. Do you smell a distinctive odor as the mixture heats up? Do you notice more than one odor as the mixture continues heating? What color is the heated mixture?

What's Going On? .
When the amino acids and sugars are heated, they interact with each other in a phenomenon known as the Maillard reaction. The molecules of the amino acids and sugars combine to form new aromas and flavors. The Maillard reaction is also responsible for the brown color of cooked foods. It normally occurs at very high temperatures, but if there is a high concentration of sugars and amino acids, then it will occur at lower temperatures. The Maillard reaction gives toast its distinctive flavor, beer its distinctive color, and self-tanning products the power to turn skin brown. It is responsible for literally hundreds of flavor compounds, and is used to make artificial maple syrup. Share & Discuss
What did you smell when you cooked the amino acid caplets? Take notes during the activity and tell us your results !


What Else Can I Try? .
  • Try mixing different amino acids together and see what aromas occur.

  • Try tasting the Maillard concoctions. Do this with friends and see what different odors each friend smells. Have each friend write down what they smell and do a poll at the end.

Share your results!


*This experiment was suggested by Harold McGee in his book The Curious Cook (San Francisco: North Point Press, 1990).


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