What You Need to Know
The emulsion forms when hydrophobic polypeptides from malt (LTP1) and iso-α-acids from hops interact at the liquid-gas interface, creating a viscoelastic film stabilized by hydrogen bonding and hydrophobic interactions.
Critical for aroma release, visual appeal, and mouthfeel in beer; techniques to enhance head retention are prized in brewing.
Key Parameters
Temperature
4°C
0°C - 15°C
Time
2 minutes
30 seconds - 5 minutes
Equipment
Nonic pint glass (promotes nucleation)Laser-etched nucleation pointsProperly cleaned glassware
Steps
- 1.
Nitrogenated stouts (Ireland): Creates cascading microbubbles via 75/25 N2/CO2 mix
- 2.
Hefeweizen (Bavaria): Wheat proteins form voluminous, unstable heads
The Science
Primary Reaction
Protein-polyphenol crosslinking