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" How do eggs affect the consistency of cupcakes and what does baking soda do to brownies? "

Dear Anne and Sue,

I just read your information on eggs. I was wondering if the eggs are what make cupcakes stiff once the carbon dioxide is released from the baking soda and salt? Are brownies not fluffy because of the lack of baking soda?

Thank you for all the help you can give me.


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Hi Christan,

Eggs do play an important role in helping cupcake and other batters make the transformation from a liquid to a cake. This transformation hinges on the protein in eggs, which coagulates during baking as the temperature increases. As the batter rises to its maximum height, it also becomes firm as a result of the protein coagulating, so baked goods such as cupcakes hold their shape once out of the oven.

Carbon dioxide (CO2) is a leavening gas that’s released from baking soda and baking powder when they’re used in batters. Salt, however, is not part of these reactions and plays no role in creating CO2.
You’re right about most brownies being denser in texture than other cakes. And those who love a dense, but soft, “fudgy” brownie contend that this is an intentional departure from the light and airy texture of most cakes. Many brownie recipes don’t contain baking powder or baking soda; these recipes tend to be for the dense, sometimes chewy, kind. Cakelike brownies usually contain a leavening agent, which helps give them their fluffy texture.

The technique you use also makes a difference in the texture of the final product. Some recipes for cakelike brownies suggest creaming the butter with sugar rather than melting it. Creaming adds air pockets to the batter. As the batter cooks, these air pockets inflate, helping creating the light texture characteristic of cakelike brownies. In contrast, recipes for dense brownies usually begin by melting the butter.

The proportions of the ingredients also contribute to the character of brownies. You’ll find hundreds of recipes, each a little different from the other, and many that claim to be the best! But that’s the fun of trying several recipes for these easy, much-loved, one-bowl wonders: You can experiment and decide for yourself.

Anne & Sue




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