Cambridge Prize Lecture Nitrate Reduction and N-Nitrosation in Brewing*

Microbial nitrate reduction is the principal route of N-nitrosamine formation in brewing. The role of different groups of brewery microorganisms possessing different mechanisms of nitrate reduction is discussed together with the influence these have on N-nitrosamine levels. The relative importance of microbial and chemical catalysis of N-nitrosamine formation in beer production is also considered and reviewed in the light of recent data from other food processing industries.