Why will loud bangs or the slamming of the oven door sometimes make cakes or souffles in the oven fall?

Souffles actually fall naturally on their own as soon as they are removed from the oven. The whipped eggs incorporate a lot of air into the dish and as it heats, the air expands. As the souflee cools, the air contracts resulting in the "deflation." Loud noises can actually send air pressure vibrations throughout the souffle and cause the heated air to be pushed out of the souffle.

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Q Why does a loud bang or an oven door opening and closing make cakes fall? J.K., Hampton. A While a cake is baking, the baking powder in the batter emits gases that cause the batter to rise. When the batter is at its maximum height, it's unstable and prone to fall because the air cells holding the gases are thin and weak. Angel food and chiffon cakes are more likely to fall from a noise or the oven door's opening because the primary leavening is beaten egg whites, which contain air pockets that expand in the cooking process.

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