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STANDARDS

NGSS: Practice: Constructing Explanations

Crosscutting Concepts: Cause and Effect; Structure and Function

Core Idea: LS1.D: Information Processing; PS1.B: Chemical Reactions

CCSS: Reading informational Text 1

Why We Love Chocolate!

Discover the science behind this tasty treat

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On Valentine’s Day, some people give loved ones flowers or a card. But the most popular gift is chocolate. People eat a LOT of chocolate, and not just on February 14. Each year, people around the world eat 8 million tons of chocolate—more than the weight of 20 Empire State Buildings! What makes chocolate so popular? The answer comes down to science!

HOW IT'S MADE

Chocolate’s key ingredient comes from the cacao (kuh-KOW) tree. This evergreen tree grows in tropical rainforests. It produces football-shaped fruit, called cacao pods. 

When the pods are ripe, farmers remove the seeds, known as cacao beans. These beans are fermented. During this process, tiny living things called microbes break down sugars, making the beans less bitter. 

Next, cacao beans are roasted and ground into a paste. Chocolate makers mix the paste with ingredients like sugar and milk and warm it until it turns to liquid. Finally, the liquid chocolate is poured into molds, where it cools and hardens.

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The average American eats about 20 POUNDS OF CHOCOLATE each year!

TASTE TEST

During these steps, many chemical reactions happen to give chocolate its unique taste. Each ingredient plays a role. Cocoa paste adds a rich, slightly bitter, flavor. Sugar makes it sweet. And milk makes it creamy.

Different amounts of ingredients lead to different flavors. For example, dark chocolate has less sugar and milk and more cocoa paste than milk chocolate. That’s what makes it less sweet and creamy.

People taste these flavors thanks to cells that cover the tongue called taste receptors. They detect chemicals in the foods you eat. Then they send signals through nerves to tell your brain if something is sweet, salty, or any other flavor!

MELT IN YOUR MOUTH

It’s not just chocolate’s taste that makes it irresistible to so many people. Another reason has to do with its melting point. The type of fat in chocolate, called cocoa butter, melts at the same temperature as the human body. That’s why when you pop a piece of chocolate in your mouth, it quickly softens, flooding your mouth with flavor.

Other chocolate ingredients have other effects. Sugar triggers a process in your brain that gives you a sense of well-being. Hundreds of other chemicals in chocolate give your body and brain a happy boost.

Humans have enjoyed chocolate for thousands of years. It continues to be a beloved treat—and it’s easy to see why!

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