Microbrewidics: A Microfluidic Platform to Investigate What Stabilizes Hop Oil Emulsions in Beer

Hop oils form microscopic emulsions in aqueous beer, but little is known about which molecules in beer stabilize these emulsions. Here we use a microfluidic platform as a tool to enable the creation of assays to explore the role of proteins in the stabilization of hop oil emulsions in beer. The terpenes linalool and α-pinene were used to form emulsions with a Kölsch-style ale on a microfluidic device (oil-in-beer emulsions). Gluten was added to these emulsions on-chip to investigate how this protein, which is present in beer, affects the stability of the emulsions. Then Brewers Clarex, an enzyme commonly used in brewing to degrade proteins, was added to digest the oil-in-beer emulsions. Our data suggest that the type and amount of proteins present in beer may affect the stability of the hop oil emulsions, which could have an impact on the shelf life and sensory quality of the beer.