The Hidden Life of Spices – National Chemistry Week 2025

“National Chemistry Week (#ACS_NCW) is celebrated this year during the week of October 19-25 with the theme “The Hidden Life of Spices.” Chemistry plays a crucial role in how spices can create various smells and flavors, while also acting as medicine or fabric dyes. Spices can be found typically as solids or in the form of oil, which is a hydrophobic liquid. Hydrophobic means that the substance does not like water. Chemists must use different methods while working in the laboratory to obtain these oils with methods including distillation, cold press, and more.

The structure of spices plays a huge role in how the spice is perceived by people. Even the smallest difference in structure can completely change how a spice tastes or smells. For example, did you know that celery and licorice have structures that have just one difference? These differences affect how receptors on our tongue and inside our nose interact with a spice, changing the way we perceive its smell and/or its taste.

There are a variety of chemicals in spices. In fact, spices are mixtures of various chemicals. Some chemicals found in spices include capsaicin, myristicin, and many more. Capsaicin is a chemical that makes peppers spicy. Myristicin is a chemical that gives nutmeg its flavor and aroma.”

Explore Educational Resources for younger children and General Interest Resources for college students and adults.

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How to Beat Spicy Pepper Heat

“Maybe you’ve heard that milk is the perfect way to extinguish that spicy food burn–but what if you can’t drink milk? This week our lactose-intolerant host, Sam, eats serrano peppers alongside lactose-tolerant George and they both try to find something that quenches the burn. Spoiler alert: One of them does a heck of a lot better than the other.”

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Watch more Reactions Science Videos on YouTube about spices:

Allspice	The World’s Most Misunderstood Spice: Allspice
Cilantro	Why Do Some People Hate Cilantro?
Garlic	You Can Taste Garlic with Your Feet!?
Kimchi	What Makes Kimchi So Delicious?
Pepper	The Chemistry of Pepper: The Spice that Changed the World
Pumpkin spice	Pumpkin spice vs. maple: Battle of the fall flavors
Salt	Why Does Salt Change the Taste of Everything?
Sriracha	The Chemistry of Sriracha: Hot Sauce Science
Vanilla	Are We Running Out of Vanilla? — Speaking of Chemistry
Wasabi	The Truth About Wasabi – Speaking of Chemistry