Omega Yeast Diacetyl Knock Out (DKO) artwork

Diacetyl Knock Out (DKO) is a series of familiar house strains engineered to knock out diacetyl formation before it starts. Each DKO strain expresses the ALDC enzyme, allowing you to streamline efficiency and quality. Strains you rely on are now more reliable.


  • Avoid diacetyl hangups with hop creep
  • Boost quality and keep tanks turning quickly
  • Diacetyl so low, it’s undetectable

Eight familiar, versatile strains to choose from:

  1. Bayern Lager DKO (OYL-433)
  2. British V DKO (OYL-431)
  3. DIPA DKO (OYL-436)
  4. Extra Special DKO (OYL-432) Formerly British Ale VIII
  5. German Lager I DKO (OYL-437)
  6. Kolsch II DKO (OYL-435)
  7. Point Loma DKO (OYL-434) Formerly West Coast Ale III
  8. West Coast I DKO (OYL-430)

The DKO series strains prevent the formation of diacetyl while maintaining the identical fermentation behaviors and flavor expressions of their parental strains. The benefit of ALDC-expressing yeast is that the pathway for diacetyl formation is stopped at the source resulting in virtually no diacetyl production throughout fermentation. When these strains are put to use, the diacetyl levels never reach sensory thresholds. Even when using the most sensitive GC-ECD methods, they stay at the lower limits of detection, giving you peace of mind.

Probrew Resource: What is the DKO series?