Which of these is NOT a key component in beer production?

In beer production, the primary ingredients are grains, hops, yeast, and water. Grains, such as malted barley, provide the sugars needed for fermentation. Hops contribute bitterness, aroma, and flavor, acting as a natural preservative. Yeast is essential for fermentation, converting sugars from the grains into alcohol and carbon dioxide.

Dairy, on the other hand, is not a component of traditional beer production. While some modern beer styles may incorporate dairy in the form of lactose (for example, in milk stouts), it is not considered a key ingredient in the overall process of creating beer. Thus, identifying dairy as not belonging to the core four components—grains, hops, water, and yeast—aligns with the established structure of brewing.