Pectinatus

Pectinatus is a genus of Gram-negative, strictly anaerobic rod-shaped bacteria in the family Selenomonadaceae. Its species Pectinatus cerevisiiphilus is a notorious beer spoiler, producing turbidity, off-odors, and unpleasant flavors in packaged beer. In brewing microbiology, these obligate anaerobes thrive in the oxygen-free environment of finished beer, making them a persistent threat despite pasteurization or filtration. Detection relies on selective culture or PCR methods, and control centers on rigorous sanitation, oxygen management, and package integrity. Pectinatus outbreaks cause significant economic losses, so breweries treat it as a key indicator organism in quality-assurance programs.