Well, you notice that baking soda and baking powder usually appear on your recipe. Do you know what is the purpose of them adding into your baked goods? Are they the same thing? Can we substitute one with another?
First of all, we must know that both baking soda and baking powder are leavening agents. Leavening agents will produce carbon dioxide and cause your baked goods to rise. While they serve the same purpose, they are used under different conditions. Why? Because they are chemically different and require different agent to activate them. They are totally NOT THE SAME THING!
Baking soda is sodium bicarbonate. When you mix baking soda with acidic agent like vinegar, it will get chemical reaction like eruption of bubbles. The reaction output is carbon dioxide. This is exactly what happen to our baked goods like cakes and breads to make it rise. In the recipe when baking soda is used you will normally find acidic ingredients like buttermilk, brown sugar, yogurt, lemon juice, vinegar, cream of tartar, molasses, applesauce, natural cocoa powder, or honey. You need these acidic ingredients to react with the baking soda to create carbon dioxide which make your baked goods rise. The right ratio of baking soda is important in your recipe. A simple rule is 1/4 teaspoon of baking soda for 1 cup of flour. Too much baking soda but not enough acid means there will be leftover of baking soda in your baked goods. The result is metallic, soapy taste in your baking products.
Baking powder contains baking soda. It is a mixture of baking soda, cream of tartar (a dry acid) and sometimes cornstarch. As baking powder already contained acid in it, it is usually used in recipe which does not feature acidic ingredients. It needs water to activate it. A lot of baking powder today are double acting. Firstly, it reacts when you combine your dry and wet ingredients together. The leavening happens. Secondly, the leavening happens again when it is heated. However, the truth is baking soda is around 4 times stronger than baking powder. Therefore, you generally need 1 teaspoon of baking soda for 1 cup of flour in recipe.
So, can we substitute one with another? Well, there are two scenarios here. One, you try to replace baking soda with baking powder. The other scenario is you try to replace baking powder with baking soda. Frankly, it is not as straight forward as you think. Let’s look at possible result of both..
Replacing baking soda with baking powder
When you replace baking powder with baking soda, you basically do not need to add additional ingredients. As mentioned previously, baking soda is 4 times more powerful than baking powder. Thus, theoretically you can replace the baking soda with 3 times as much as the baking powder to create the same rising effect. You probably think that this is pretty a simple and effective solution. But don’t forget that too much baking powder in your baked goods will result in a chemical or bitter taste.
Replacing baking powder with baking soda
On the other hand, replacing baking powder with baking soda need to incorporate additional ingredients. Unlike baking powder, baking soda does not contain acid. Therefore, you will need to add acidic ingredients such as cream of tartar to activate it. Again, you need to carefully adjust the amount of additional ingredient to balance the overall recipe.
All in all, baking soda and baking powder are totally different thing. Trying to substitute one with another is not advisable. And one more point is both your baking soda and baking powder only last for 3 months after you open it. So make sure you house keep them in a proper manner to ensure desired rising effect on your baked goods.