The Science of Baking

Learn why the acidity of a batter determines whether you use baking powder, baking soda, or a combination.

When reading over a baking recipe, I always check the type of leavening ingredients against ingredients high in acid. That sounds a lot more complicated than it is!

The batter for baked goods needs to be near a neutral pH (around 7.0), neither too acidic or too alkaline. If the batter is too high in acid, the resulting product will be light in color and may taste too sour. If the batter is too alkaline, the product will be heavy and will taste bitter. Baking soda is used to stabilize the batter's pH.

Ingredients high in acid include citrus juices, buttermilk, brown sugar, vinegar, molasses, sour cream, honey, yogurt, and cocoa. If the recipe you are making includes one or more of these ingredients and uses only baking powder, reduce the baking powder amount by 1/2 tsp. and add 1/2 tsp. baking soda. Your baked goods will turn out much better, with a more tender crumb, better browning, and balanced flavors.

For instance, in Orange Blueberry Muffins, the original recipe called for 1 cup milk. I wanted to add orange flavor to the tender muffins, so I used 3/4 cup milk and 1/4 cup orange juice. Orange juice is an ingredient high in acid, so I knew I needed some baking soda to offset the acidity, keeping the batter more neutral in pH, so it would brown evenly and rise correctly.

The more you know about the science of food, the better a baker you'll be!