Dear Home Ec 101,
I’m going to try to do a lot of baking this holiday season, can you explain the difference between baking powder and soda? If I run out what can I use as a substitute?
Rising in Raleigh
I’ve mentioned before that baking is a matter of chemistry. Both baking soda and powder are leavening agents. This means they react to create bubbles of carbon dioxide which helps baked goods rise.
Baking soda, also known as sodium bicarbonate, is a basic salt and reacts with acidic liquid ingredients to create the bubbles of carbon dioxide. It reacts immediately which is why baked goods containing only baking soda need to be baked soon after mixing the wet and dry ingredients.
Baking powder contains both baking soda and cream of tartar, which is an acid salt, creating a reaction when dissolved in any liquids. Double acting baking powders react not only when liquids are first added, but also with the heat of baking.
To substitute for baking powder use two parts of cream of tartar for every part baking soda. (For three teaspoons you would mix two teaspoons cream of tartar and one teaspoon baking soda)
If you are out of baking soda and only have baking powder use approximately three times more baking powder than soda required by the recipe. For better results also try to substitute a neutral liquid if possible. For example, if a recipe calls for buttermilk, use plain milk instead.
Both baking soda and baking powder lose effectiveness with time. Baking powder loses its potency more quickly as humidity causes the reaction to occur.
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