What Does Baking Powder Do?

Baking powder is used as an additive to help baked goods rise. While some baked goods are yeast-raised, such as whole-wheat bread and pizza dough, others are chemically leavened, using either baking soda or baking powder. Examples include biscuits, cakes and pancakes. Baking powder is a blend of ingredients, which, when exposed to water and heat, help batters rise, making the final product light and fluffy.

About Baking Powder

What It Is Made Of

Baking powder is a blend of baking soda, also known as bicarbonate of soda, alkali agent and cream of tartar, which is acidic. It also often contains a filler, such as corn or rice flour, which acts as an anti-caking agent. Corn and rice flour prevent baking powder from clumping, because they absorb excess moisture from the air.

How It Works

When any liquid is added to baking powder, the alkali and acidic agents in the powder undergo a chemical reaction. As a result, carbon dioxide, a gas, is produced. The result is small bubbles that form in batter or dough, which cause the dough to rise, leading to light, fluffy foods.

Quantities Needed

In general, 1 to 2 teaspoons of baking powder, roughly 5 to 10 grams, are needed for every cup of all-purpose flour. The exact amount required depends on the recipe. Too much baking powder can lead to excessive browning and a bitter, soapy taste in foods. Too little yields flatter, under-raised foods.

Testing for Freshness

Baking powder, can, over time, lose its leavening abilities. To test if the baking powder is fresh, add 1/4 teaspoon of baking powder to 1/2 cup of hot water, either boiled or from the tap. If the powder fizzes immediately after it is added to the water, then it is fresh and can be used. If it does not fizz -- or only fizzes a little -- the baking powder has lost its freshness and should be discarded.

Making Your Own

If you do not have baking powder at hand, you can make it with other standard baking ingredients. A basic recipe for baking powder is to combine:

  • 1/4 teaspoon of baking soda
  • 1/2 teaspoon of cream of tartar
  • 1/4 teaspoon of corn starch

This makes 1 teaspoon of baking powder.

Substitutes for Baking Powder

Baking powder can also be substituted for just baking soda and an acidic compound that is not cream of tartar. To replace 1 teaspoon of baking powder, use a 1/4 teaspoon of baking soda and 1 cup of buttermilk or yogurt. The buttermilk or yogurt can be used in place of milk, cream or water in a recipe.