Buzz
A few minutes after you place a tray of cookie dough in the oven, a loud clanging sound echoes from inside. Even if it’s something you’ve experienced many times before, it can still be jarring.
This noise occurs because metal expands when exposed to the high temperatures of the oven. However, the process isn’t uniform—certain areas of the pan may expand more quickly or further than others. If the pressure becomes too much, the sheet can bend, causing the jarring sound that startles you.
Thicker baking sheets are better at withstanding the stress from heat expansion. So opting for a “commercial-grade” or “double-thick” aluminum baking sheet could help you avoid the issue. The noise isn’t the only concern; a warped pan makes it difficult to handle and can also lead to uneven baking or roasting. As the Basically blog explains, a rolled-edge rim is just as crucial as thickness in preventing misshaped pans. It helps stabilize the edges, keeps the bottom flat, and ensures even heating. Even a well-built, rolled-edge baking sheet might still make a little noise, but it will return to its original shape more easily once the temperature stabilizes.
Thin, rimless sheets without reinforcement are more prone to warping and staying deformed, similar to how it’s much easier to twist the flimsy lid of a plastic container out of shape than to bend the entire sturdy box itself.
