Which of these is used primarily for flavor enhancement in cooking?

Salt is primarily used for flavor enhancement in cooking because it has the unique ability to enhance the natural flavors of other ingredients. This compound works by suppressing bitterness and highlighting sweetness, which allows other flavors to become more pronounced. The use of salt can transform a dish, making it taste more balanced and complex. It also plays a role in the chemical reactions during cooking, such as in the Maillard reaction, which contributes to the browning and development of flavors in food during cooking.

In contrast, oil is primarily used for cooking methods like frying or sautéing and contributes to the texture and moisture of dishes rather than acting mainly as a flavor enhancer. Flour is mostly used as a thickening agent or as a base in baking and does not primarily serve to enhance flavor. Sugar, while it does enhance sweetness and can complement flavors, is not as universal a flavor enhancer as salt, which affects a broader range of taste profiles in various dishes.