Washington State University’s resident feline scientist, Dr. Universe, answers a tasty question from Skye, 10, of the United Arab Emirates: Why does bread expand in the oven?
With help from WSU Breadlab head baker Mel Darbyshire, Dr. Universe explains that bread rises because of yeast, a tiny living fungus that feeds on sugar and releases carbon dioxide gas through a process called fermentation. Those trapped gas bubbles are what make bread fluffy and airy.
Readers also learn how kneading dough creates a stretchy gluten network that traps the gas, why dough “proofs” before baking, and what causes the dramatic “oven spring” that happens when bread first hits the heat. The story also explores the chemistry behind crust formation, including the Maillard reaction that gives bread its brown color and toasty flavor.
Along the way, Dr. Universe breaks down complex baking science into kid-friendly explanations, showing how microscopic organisms and chemistry work together to turn simple ingredients into bread and pizza dough.
