Baking Soda Leavening and Baking Powder Substitute

Storing baking soda and cream of tartar separately instead gives you a permanent leavening system from two shelf-stable powders that each last for decades.

• Baking soda (sodium bicarbonate)
• Cream of tartar (potassium bitartrate)
• Optional: cornstarch or arrowroot (to prevent premature reaction in humid storage)
• Optional: vinegar, yogurt, buttermilk, lemon juice, or other household acids

1. To make homemade baking powder fresh for a batch, mix 1 part baking soda with 2 parts cream of tartar. For example, 1/3 teaspoon baking soda plus 2/3 teaspoon cream of tartar equals 1 teaspoon of baking powder, which can substitute directly for commercial baking powder in any recipe. Mix only what you need for each batch; the homemade version starts reacting as soon as it meets moisture, so store it dry and use it promptly.
2. To mix a small jar in advance for convenience, add 1 part cornstarch or arrowroot to the baking soda and cream of tartar. The starch absorbs ambient humidity and keeps the two reactive components from reacting with each other during storage. Kept tightly sealed and dry, the jar stays usable for several months; test a pinch before relying on an older batch.
3. For recipes that already contain acidic ingredients like buttermilk, vinegar, yogurt, or lemon juice, use 1/4 to 1/2 teaspoon baking soda per cup of flour with no cream of tartar needed; the acid already in the recipe activates the soda. Mix wet and dry ingredients together quickly and move the batter to the heat source right away because the leavening reaction starts immediately and weakens if the batter sits.
4. This system works well for pancakes, biscuits, cornbread, camp bread, bannock, and flatbreads cooked in a cast-iron skillet or Dutch oven. To test cream of tartar after long storage, mix a pinch with a pinch of baking soda in warm water; vigorous fizzing means it is still active.

Store both components in airtight, dry containers. Both last indefinitely when kept sealed, dry, and free of contamination. Store cornstarch or arrowroot the same way. Keep all three in your long-term food storage as a permanent leavening solution. Best container: sealed HDPE container or glass jar, keep moisture-free. Avoid metal in humid conditions (promotes corrosion). See the Containers section.