The difference between baking soda and baking powder

1，Differences in Chemical Composition

Baking Soda, also known as sodium bicarbonate (NaHCO3), is a single component. Baking powder, on the other hand, is a composite ingredient that typically contains sodium bicarbonate as a fermenting agent, along with acid salts such as sodium dihydrogen phosphate or potassium aluminum sulfate, and corn starch, to absorb moisture, maintain a dry environment, and ensure effective chemical fermentation.

2，Different fermentation mechanisms

Baking soda needs to react in an acidic environment to release carbon dioxide gas, causing the dough to expand. For example, when making baked goods such as cookies and pancakes, acidic ingredients such as yogurt, lemon juice, or vinegar react with baking soda to help the pastry ferment. Due to the presence of acidic salts, baking powder does not require an acidic environment to react, and can release carbon dioxide directly during the process of adding water and heating. It is suitable for dough of various pH values.

3，Differences in usage scenarios
Due to the need for acidic ingredients to be used in combination with baking soda, it is usually used for baked goods that already contain acidic ingredients in the formula. The independent fermentation ability of baking powder makes it more widely applicable and can be used in almost all types of baking processes. In addition, baking powder is also commonly used for baked goods that require quick reactions, such as soft cakes or fast baked bread.

4，Stability of storage and performance

Baking soda has good stability and can be stored for a long time as it remains dry and does not come into contact with any acidic substances. Although baking powder is also stored in a dry state, once opened, it needs to be sealed to avoid absorbing moisture and carbon dioxide from the air, which can weaken its fermentation ability. When used, the effect of baking powder is more consistent and reliable, and will not be affected by other components in the dough (such as acidity).