What does the term "microfoam" refer to in coffee preparation?

The term "microfoam" specifically refers to a fine, velvety foam created during the steaming process of milk. This type of foam is characterized by its small, uniform bubbles that result in a smooth texture, essential for crafting quality espresso drinks like lattes and cappuccinos. The process of creating microfoam involves technique in both the steaming and stretching of milk, which incorporates air gently to achieve that desirable consistency.

In contrast, the other options describe different aspects of milk or foam that do not align with the definition of microfoam. For instance, large bubbles are typically associated with poorly steamed milk and do not contribute to the silky mouthfeel that microfoam offers. Chilled milk for iced beverages does not involve the aeration or steaming that is necessary for producing microfoam. Lastly, a frothy layer added after brewing does not capture the same process involved in creating microfoam, which is integral to the drink-making itself rather than a topping or garnish.