How it works
A recipe chooses the leavener based on its other ingredients and the desired browning, flavor, and rise. Substituting one for the other changes the chemical balance and can leave a metallic taste or weak lift.
What people often miss
Most modern baking powder is double acting, producing some gas when mixed and more when heated. Both products lose effectiveness over time when exposed to moisture.
Why this question comes up
The similar names and appearance make these two pantry staples easy to confuse.
Key points
- Baking soda is sodium bicarbonate and needs an acid plus moisture to release carbon dioxide. Baking powder contains baking soda along with powdered acids and usually activates in stages.
- A recipe chooses the leavener based on its other ingredients and the desired browning, flavor, and rise. Substituting one for the other changes the chemical balance and can leave a metallic taste or weak lift.
- Most modern baking powder is double acting, producing some gas when mixed and more when heated. Both products lose effectiveness over time when exposed to moisture.
Bottom line
Baking soda is sodium bicarbonate and needs an acid plus moisture to release carbon dioxide. Baking powder contains baking soda along with powdered acids and usually activates in stages.
Source and verification
This Answer was checked against USDA FoodData Central: Sodium Bicarbonate. Follow the source for the full official explanation and any later updates.