Experts in both the laboratory and brewery understand that barley protein affects a bubble’s surface viscosity and tension. For years, the assumption has been that beer foam stability mainly stems from the interactions between these bubbles’ protein-rich surface layers. But after numerous experiments (and countless critical test pours) researchers are now better understanding beer foam’s underlying mechanics. A renowned specialty of the monastic order of the same name, a Trappist’s surface viscosity is much less influential. The team identified lipid transfer protein 1 (LTP1) as the primary determinant in beer foam stabilization.