Baking Soda vs. Baking Powder

Why do some recipes call for baking soda, some for baking powder, and others for both?

Why do some recipes call for baking soda, some for baking powder, and others for both?

Baking soda and baking powder are both leaveners that, when activated, form carbon dioxide; this gas, in turn, causes batters and doughs to rise. Baking soda is activated when mixed with a moist, acidic ingredient, such as sour cream. Baking powder already contains acid (as well as baking soda) so is activated by moisture alone. (Or, in the case of double-acting baking powder, first by moisture and then by heat.)

We baked three batches each of cornbread (made with acidic buttermilk) and sugar cookies (made without acidic ingredients) using different leaveners: baking soda, baking powder, and a 50-50 mix. The differences were striking. Both the cornbread and the cookies made with only baking soda were deep brown; baking soda increases browning because it makes doughs and batters more alkaline. The cornbread had a dense, heavy crumb, and the cookies spread instead of rising. Cornbread made with baking powder alone was bright yellow with an open crumb, but it tasted sour and metallic. The cookies, while pale, were crisp and spread very little. The combination of baking powder and soda worked best in the cornbread, producing a golden-brown bread with good height and an open crumb, but tasters found the cookies made with the combination “pasty.”

THE BOTTOM LINE Baking soda promotes browning but leavens only in combination with acidic ingredients. Baking powder leavens without acidic ingredients. Many recipes call for both. Now find a trustworthy recipe and follow it!


BAKING POWDER ALONE: This cornbread is bright yellow and tall, but also slightly sour and metallic-tasting



This cornbread is dark and squat.


BAKING POWDER PLUS BAKING SODA: This cornbread benefits from the lift of baking powder and the browning action of b


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