Baking soda (sodium bicarbonate) is used in baking for several essential reasons:
Leavening agent: Baking soda is a leavening agent, which means it helps baked goods rise by producing carbon dioxide gas when it reacts with acidic ingredients, such as buttermilk, yogurt, vinegar, lemon juice, or certain types of fruits (e.g., bananas). The carbon dioxide gas forms bubbles in the dough or batter, causing it to expand and creating a light and airy texture in the finished product.
Quick action: Baking soda reacts immediately when it comes into contact with acidic ingredients, making it ideal for recipes that require immediate leavening. This quick reaction is why it's often used in recipes like pancakes, muffins, and other quick breads.
Neutralizes acidity: Baking soda is an alkaline compound, and when it reacts with acidic ingredients, it neutralizes their acidity. This is particularly important in recipes that have acidic components, as it helps balance the pH and ensures proper browning, texture, and flavor.
Minimal taste interference: Baking soda has a mild flavor, so it doesn't significantly impact the taste of the baked goods. This allows the other flavors in the recipe to shine.
Economical: Baking soda is an inexpensive ingredient, making it a cost-effective leavening option for baking.
It's important to note that baking soda needs an acidic ingredient to activate and produce carbon dioxide gas. If you use baking soda in recipes that don't contain enough acidity, the baked goods may taste bitter, and the texture may be dense and flat. In such cases, it's better to use baking powder, which contains both baking soda and a dry acid (usually cream of tartar) to provide the necessary leavening.
In summary, baking soda is a valuable ingredient in baking due to its leavening properties, quick action, ability to neutralize acidity, minimal taste interference, and affordability. When used correctly with the right acidic ingredients, it contributes to delicious, light, and well-textured baked goods.