Difference Between Baking Soda and Baking Powder

Explanation

Baking soda (sodium bicarbonate) is a base that reacts with acidic ingredients like buttermilk, yogurt, lemon juice, or vinegar to produce carbon dioxide bubbles. These bubbles make baked goods rise. Without acid in the recipe, baking soda won't work properly.

Baking powder is a complete leavening agent containing baking soda, an acid (usually cream of tartar), and a buffer (usually cornstarch). Most baking powder is double-acting, meaning it reacts once when wet and again when heated.

Recipes are formulated with specific leaveners for a reason. Using the wrong one or the wrong amount can result in flat, dense, or oddly flavored baked goods. Follow recipes carefully for best results.

Too much baking soda leaves a soapy, metallic, or bitter taste in baked goods because the excess sodium bicarbonate is not neutralized by enough acid. A typical ratio is 1/4 teaspoon of baking soda per 1 cup of flour when the recipe includes acidic ingredients. Baking powder is used at roughly 1 teaspoon per 1 cup of flour. Many recipes call for both: the baking soda neutralizes the acid in ingredients like buttermilk or brown sugar (which contains molasses, an acid), while baking powder provides additional lift without requiring more acid.

The chemical reaction between baking soda and acid happens immediately upon contact with liquid, which is why batters containing only baking soda should be baked right away. Double-acting baking powder is more forgiving because its second reaction occurs at 140-180 degrees Fahrenheit in the oven, so batter that sits on the counter for 15-20 minutes will still rise properly. Single-acting baking powder (less common today) reacts only when wet, requiring immediate baking similar to baking soda. Baking soda has an indefinite shelf life when stored dry and sealed, while baking powder typically loses potency after 6-12 months once opened because moisture in the air triggers the acid and base to slowly react inside the container.

Things to Know

• To substitute baking powder for baking soda, use 3 times as much baking powder, but results may vary.
• Old baking powder loses potency; test by adding to hot water - it should bubble vigorously.
• Some recipes use both to balance flavor and provide optimal rise.
• Self-rising flour already contains baking powder and salt (typically 1.5 teaspoons baking powder and 1/4 teaspoon salt per cup of flour), so adding more leavener to self-rising flour recipes can cause baked goods to rise too fast and then collapse.