In this experiment, you’ll bake two batches of cookies: one made with brown sugar and one made with white sugar. Then, you’ll do a taste test to find out whether the kind of sugar you used affects your cookies’ flavor and texture.
Measure these ingredients TWICE:
Measure these ingredients ONCE:
Make a prediction: Do you think cookies made with brown sugar will taste the same as or different from cookies made with white sugar? Why do you think so?
Make cookies with brown sugar: Adjust oven rack to middle position and heat oven to 350 degrees. Line rimmed baking sheet with parchment paper.
In medium bowl, whisk together 1 cup plus 1 tablespoon flour, ¼ teaspoon baking soda, ¼ teaspoon salt, and ⅛ teaspoon baking powder.
In large bowl, whisk brown sugar and 7 tablespoons melted butter until smooth and no lumps remain, about 30 seconds. Add 1 egg yolk and 1½ teaspoons vanilla and whisk until well combined, about 30 seconds.
Add flour mixture to sugar mixture and use rubber spatula to stir until just combined and no dry flour is visible, about 1 minute.
Place baking sheet in oven. Bake cookies until edges are beginning to set but centers are still soft and puffy (cookies will look raw between cracks and seem underdone), 15 to 20 minutes.
Use oven mitts to remove baking sheet from oven and place on cooling rack (ask an adult for help). Use masking tape and marker to label cooling rack “Brown Sugar.” Let cookies cool completely on baking sheet, about 30 minutes.
Make cookies with white sugar: While cookies with brown sugar cool, repeat steps 2 through 8 to make cookies with white sugar, using clean bowls, whisk, and rubber spatula. (Don’t forget to use white sugar in step 4!) Use masking tape and marker to label second cooling rack “White Sugar.” Let cookies cool completely on baking sheet before tasting, about 30 minutes.
(Don’t read until you’ve completed the experiment!)
When we tried this experiment in the Recipe Lab, we observed some big differences between the cookies made with brown sugar and the ones made with white sugar. How about you?
Sugar does more than make cookies sweet—it also affects their texture and their flavor. First things first: Brown sugar is just white sugar with molasses added to it. Molasses gives brown sugar more flavor than white sugar (that’s why the two cookies tasted different). It also adds more water to brown sugar. That’s one reason the brown sugar cookies had a moister, chewier texture.
Another reason? Sugar is hygroscopic (“hi-grow-SKAH-pick”)—it’s really good at absorbing and holding on to water from its surroundings. Brown sugar is more hygroscopic than white sugar, which keeps our brown sugar cookies moist and bendable and makes our white sugar cookies crispier.
Finally, thanks to that molasses, brown sugar is a little bit acidic. The acidic molasses reacts with the baking soda in our cookies to produce bubbly carbon dioxide gas, making the brown sugar cookies a bit thicker and puffier than the white sugar cookies.
Lots of cookie recipes call for white and brown sugar. This can give you the best of both worlds in your cookies’ texture and flavor. Other recipes use one type of sugar or the other, depending on the flavor and texture they’re aiming for. Once you understand this sugary science, the wide world of cookies can be yours!