Occurrence of Pectinatus and Megasphaera in the major UK breweries

The occurrence of beer spoilage bacteria belonging to the genera Pectinatus and Megasphaera in ten major UK breweries was investigated. The sampling points were selected from fermentation areas, beer conditioning areas and beer bottling and canning sites. Multiplex PCR methodology was used for detection of three Pectinatus and three Megasphaera species using species specific primers. The presence of six Lactobacillus species was also examined. Overall, 117 samples were analysed from ten breweries; six samples were positive for the presence of Pectinatus species and three samples were positive for the presence of Megasphaera species, while 34 samples were positive for the presence of Lactobacillus species. Lactobacillus species appeared to be the major potential spoilage microorganisms. Although none of the actual beer samples were found to be positive for Pectinatus and Megasphaera species, their occurrence in aerobic brewery environments indicates sanitation problems and revealed the presence of highly established biofilms in some breweries.