Overview

• ETH Zurich and Eindhoven University of Technology published seven years of research on August 26 identifying fermentation degree as the key driver of beer-foam stability.
• In single-fermentation lagers, foam persists mainly through surface viscosity, whereas double-fermented beers form elastic two‑dimensional protein networks that strengthen films.
• Triple-fermented styles stabilize heads via Marangoni flows triggered by surfactant-like fragments of lipid transfer protein 1 (LTP1) that reduce surface tension.
• High‑resolution imaging and rheometry directly visualized the thin films between bubbles, linking LTP1 structures and interfacial behavior to foam longevity.
• The findings offer brewers levers to tune heads and are being applied with industry partners, including a major brewery and Shell, with broader prospects for greener surfactants and foam control in lubricants and food foams.