What is "crema" in espresso?

Crema refers to the golden, frothy layer that forms on the surface of a well-extracted shot of espresso. It is created during the brewing process when hot water forces through the finely ground coffee under pressure. The emulsification of coffee oils and the release of gases during extraction produce this rich, caramel-colored foam, which not only enhances the visual appeal of the drink but also contributes to its flavor and aroma. A good crema indicates a high-quality extraction, reflecting freshness and proper brewing technique, making it a desirable characteristic in espresso.