What is Beer Foam?

Beer foam, also known as the head, is the frothy layer that forms at the top of a freshly poured beer. This creamy crown is created by bubbles of carbon dioxide gas rising to the surface, where proteins from the malt and hops form a stable structure around them.

Characteristics of Quality Foam

• Density: Should be creamy and tight, not bubbly or loose
• Retention: Should last several minutes without dissipating
• Lacing: Leaves patterns (lace) on the glass as the beer is consumed
• Color: Varies from bright white to tan depending on beer style
• Height: Typically 1-2 inches, though varies by beer type

Factors Affecting Foam Quality

Several elements influence beer foam formation and retention:

1. Protein content from malted barley
2. Hop iso-alpha acids
3. Carbonation level
4. Glass cleanliness (dirty glasses kill foam)
5. Pouring technique
6. Beer temperature
7. Alcohol content (higher alcohol can reduce foam)