You might be able to save yourself a trip to the store by using one of the following options.
Substituting Baking Powder for Baking Soda
Cream of tartar, lemon juice, buttermilk, or some other acidic ingredient is needed when substituting baking soda for baking powder because baking soda needs an acid to make it work. Baking powder (1 teaspoon) can be replaced with 1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar (Joy of Baking recommends adding 1/4 teaspoon of cornstarch as well). Another option is to use 1/4 teaspoon baking soda + 1/2 cup buttermilk and reduce other liquid in the recipe by 1/2 cup.
Substituting Soda for Baking Powder
Baking soda (1/2 teaspoon) can be replaced with 2 teaspoons of baking powder. However, baking soda requires an acidic ingredient such as lemon juice, vinegar, cream of tartar, buttermilk, or yogurt in the recipe, but baking powder does not, so it may be necessary to replace the acidic ingredient with a similar non-acidic ingredient when replacing baking soda with baking powder. Unfortunately, this can affect the flavor of certain recipes, which is why many cooks say that there is actually no good substitute for baking soda.
Cream of Tartar Substitutes
Cream of tartar is most often used either to help baking soda make baked goods rise or to stabilize egg whites in meringues. When used with baking soda, cream of tartar is the acidic ingredient that helps the baking soda work, so you can replace it with another acidic ingredient. One teaspoon of cream of tartar can be replaced with one to three teaspoons of lemon juice or vinegar in recipes that also call for baking soda (some sources recommend a one-to-one substitution; others recommend three to one, so experiment to see what works best with your recipes). With meringues, you can usually get away with just leaving the cream of tartar out, or replace it with lemon juice in a one-to-one ratio, though this may affect the flavor.
Another option is to replace both the baking soda and cream of tartar in the recipe with baking powder. In this case, use a teaspoon of baking powder for each 1/4 teaspoon of baking soda + 5/8 teaspoon cream of tartar (you may not be able to get this exact, but aim to be as close as possible).
Note: When using substitutes, the flavor and texture of baked goods may be affected.
For more baking substitution options, see the main Cooking and Baking Ingredient Substitutions page.
- Allrecipes.ca. (2014). “Common Ingredient Substitutions.” http://allrecipes.com/howto/common-ingredient-substitutions/
- JoyofBaking.com. (2014). “Baking Ingredient Substitution Table.” http://www.joyofbaking.com/IngredientSubstitution.html
- New Health Guide. (2013). “Baking Soda Substitutes.” NewHealthGuide.org. http://www.newhealthguide.org/Baking-Soda-Substitute.html
- Stradley, L. (2004). “Cream of Tartar: Shelf Life of Cream of Tartar – Cream of Tartar Substitute.” WhatsCookingAmerica.net. http://whatscookingamerica.net/Q-A/CreamTartar.htm