Baking Powder
A chemical leavener consisting of baking soda, dry acids, and cornstarch, activated by moisture and heat.
1 Tsp Baking Powder = 4g • Leavening ratio: 1 Tsp baking powder lifts 1 cup of flour
Baking powder is a complete chemical leavening agent that contains both a base (sodium bicarbonate) and dry acids (such as cream of tartar or sodium acid pyrophosphate), along with an inert starch (usually cornstarch). The cornstarch plays two critical roles: it absorbs ambient moisture to prevent the acid and base from reacting in the container, and it keeps the powder free-flowing. Most modern baking powders sold in grocery stores are 'double-acting'. This means they react twice: first, when the powder dissolves in liquid ingredients at room temperature, and second, when the mixture is heated in the oven (typically above 140°F / 60°C). This dual reaction provides a reliable, controlled rise throughout the baking process.
Because baking powder contains its own acid, it does not require acidic ingredients in the batter to activate, making it ideal for neutral batters like sponge cakes and sugar cookies. Using too much baking powder can cause batters to rise too quickly and collapse, leaving large air pockets and a bitter taste.
Using expired baking powder. The chemical acids degrade over time when exposed to air and humidity. Using old powder results in flat, dense cakes and heavy cookies.
Widely available globally. Some brands contain aluminum-based acids, which can leave a metallic taste in light cakes. Look for 'aluminum-free' labels.
Use in neutral batters like sponge cakes, sugar cookies, and quick breads that lack acidic ingredients to activate baking soda.
Replace 1 teaspoon baking powder with 1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar.
Store in a cool, dry place in a tightly sealed container. Test freshness by mixing 1 teaspoon of baking powder into 1/2 cup of warm water it should bubble vigorously.
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