Glossary
Pediococcus
A lactic-acid bacterium used in mixed fermentation, notable for producing a viscous "ropiness" that later clears as Brettanomyces breaks it down.
Pronounced ped-ee-oh-KOK-us.
Also called pedio.
The full record
Pediococcus has its own catalogue entry with the detail this page summarises — causes, thresholds, related styles and evidence.
Pediococcus — A hop-tolerant lactic bacterium central to lambic and Flemish sours, notorious for a slimy intermediate stage.
The ropy phase alarms brewers new to mixed fermentation, because the beer becomes noticeably thick and slimy. In a lambic or Flemish red it is a normal stage, and it resolves. Pediococcus also produces diacetyl, which Brettanomyces subsequently consumes.
Related
- Lactobacillus — The faster-acting souring organism.
- Brettanomyces — The organism that clears up after it.
More vocabulary
Adjunct · Aroma hop · Base malt · Bittering hop · Black malt · Brettanomyces · Candi sugar · Chocolate malt · Crystal malt · Dextrin
See every term on the glossary index.
Last reviewed 2026-08-16.