) The Enterobacteriaceae Members of the Enterobacteriaceae may be isolated from wort in significant numbers. Such bacteria are referred to as "wort bacteria and normally only survive the initial stages of fermentation. A number of genera have been isolated (some names used earlier may not conform to modern taxonomic usage including Citrobacter Enterobacter, Escherichia, Hafnia and Klebsiella. These may be accompanied by non-Enterobacteriaceae described as Pseudomo- nas and Achromobacter