What is the function of a coffee grinder?

The primary function of a coffee grinder is to break down coffee beans into smaller particles for brewing. When coffee beans are ground, their surface area is increased, allowing for better extraction of flavors and aromas during the brewing process. This grinding process can be done to various coarseness levels, which affects the brewing method; for example, a coarse grind is typically used for French press coffee, while a fine grind is suitable for espresso.

While brewing coffee automatically relates to a different aspect of coffee preparation, preserving the freshness of whole beans is more about storage rather than the grinding process itself. Similarly, mixing different varieties of coffee beans is a method of creating blends and does not represent the fundamental purpose of a grinder, which is to prepare coffee for brewing by grinding the beans. Therefore, the correct answer highlights the grinder's essential role in making the coffee ready for the brewing process.