In a cake recipe, the purpose of baking powder is to act as the leavening agent, even if there is no baking soda or yeast listed separately in the ingredients. Baking powder is a leavening agent on its own, and it provides the necessary carbon dioxide gas to make the cake rise and create a light and airy texture.
Baking powder is a combination of an alkaline ingredient (usually baking soda) and an acidic ingredient (often cream of tartar). When combined with a liquid and exposed to heat during baking, baking powder undergoes a chemical reaction that produces carbon dioxide gas bubbles. These bubbles get trapped in the cake batter, causing the cake to rise and become fluffy.
The absence of baking soda or yeast in the ingredients list suggests that the recipe relies solely on baking powder to provide the leavening action needed to achieve the desired texture in the cake. This is a common approach in many cake recipes, especially those that require a quick and easy preparation process, as baking powder eliminates the need for additional rising time or complex fermentation processes.
To ensure the success of your cake, it's crucial to use the correct amount of baking powder as specified in the recipe. Too much baking powder can lead to an overly airy and coarse texture, while too little may result in a dense and flat cake. So, always follow the recipe instructions carefully to achieve the best results.