You Can Substitute Yogurt For Baking Powder. Here's How
It never fails that you just happen to be running low on an ingredient that's a pantry staple right when you need it most. Rather than trying to run to the store to get more baking powder to finish the dish you are working on, it's helpful to know of a few substitutes that will do the trick in a pinch. That's also why you should understand what baking powder is and how it works.
Baking powder is a leavening agent used to add volume and give baked goods a lighter texture or crumb. Unlike baking soda, which is just sodium bicarbonate, baking powder also has an acid, like cream of tartar, mixed in. This combination reacts when it comes into contact with water and it releases carbon dioxide gas, which makes bubbles. The bubbles expand and are responsible for adding volume to whatever it is you are baking. This is why plain yogurt can be used to replace baking powder (via Healthline).
Here's how to make the swap
Yogurt is acidic, just like the cream of tartar in baking powder. When the milk it is made with ferments, the pH level of the yogurt decreases, which causes the acidity of the yogurt to increase. That's why you can combine plain yogurt with baking soda to get the combination of the acid with the sodium bicarbonate (via The Pioneer Woman). The two components are present, so the reaction will still happen.
It is important to remember that by adding yogurt to the recipe, you are also adding more liquid. However much plain yogurt you add to the recipe, you also need to reduce the same amount of liquid elsewhere, such as the amount of water or milk that's called for.
For every one teaspoon of baking powder you need in a recipe, you should use half a cup of plain yogurt with a quarter teaspoon of baking soda. This substitution will give you just the right amount of lift in the batter that you would otherwise get from baking powder.