THE INFLUENCE OF OXYGEN ON THE PRODUCTION OF DIACETYL DURING FERMENTATION AND CONDITIONING

Abstract

Although varying concentrations of oxygen in wort at pitching do not affect the production of diacetyl, its availability during fermentation has a significant effect. The enhanced production of diacetyl resulting from access of oxygen during fermentation is caused by its effect in increasing yeast growth and in altering the balance of amino acids relative to sugars and not by a direct oxidation of acetoin. Oxygen has no effect upon the concentration of diacetyl during storage and conditioning, provided that the beer is free from contamination.