What is the purpose of raising agents in food preparation?

Raising agents play a vital role in food preparation by introducing gas into a mixture, which causes it to rise during cooking. This process is fundamental in creating the texture and structure of baked goods. When raising agents, such as baking powder or yeast, are included in a recipe, they produce carbon dioxide gas. This gas forms bubbles, which expand when exposed to heat, ultimately leading to a light and airy final product. This function is especially important in items like bread, cakes, and soufflés, where a well-aerated structure is essential for the desired outcome.

The other options, while relevant to food preparation, do not accurately describe the primary role of raising agents. Preserving food, adding flavor, and increasing shelf life are different aspects of food science that involve other techniques and ingredients.