Successfully swapping yeast for baking soda and lemon juice is easier than you may think, although the texture of your baked good will typically be slightly coarser than one baked with yeast. According to Margaret M. Wittenberg, author of the book, "New Good Food," baking soda is the only leavening agent that you need as long as you have enough lemon juice in the mix. Lemon juice’s acidity neutralizes the baking soda, releasing carbon dioxide. The carbon dioxide presses against the batter as it bakes, giving it a similar rise to what you'd achieve by using yeast.
Preheat your oven and prepare your baking dish by greasing it or spraying it with cooking spray. Once you have the dough or batter mixed, you need to bake it as soon as possible to maximize the leavening power of the lemon juice and baking soda.
Mix your wet ingredients in a medium mixing bowl according to your recipe's instructions and set the bowl aside. Many recipes call for a specific amount of beating and/or creaming of ingredients such as sugar and butter or eggs. This is critical for making sure you've incorporated the right amount of air in the wet ingredients.
Use a scoop, fork or whisk to fluff your flour before measuring it. Aerating the flour helps lighten it up, giving you a better, lighter result. After fluffing the flour, measure out the amount of flour as specified in your recipe. Level the measuring cup to give you an exact measurement before placing the flour in a separate mixing bowl.
Measure 1/4 teaspoon of baking soda for every 1 cup of flour in your recipe. Add it to your dry ingredients and whisk well to combine. Alternatively, you can add the dry ingredients to a sieve and sift them together into your bowl.
Combine your wet and dry ingredients according to your recipe’s directions.
Measure 1 tablespoon of lemon juice for every 1/4 teaspoon of baking soda that you're using. Mix the lemon juice into your dough.
Place the dough into your prepared baking dish and bake immediately.