Effects of Pasteurization or Added Sulphite on the Microbiology of Stored Vacuum Packed Baconburgers

SUMMARY The flora of untreated vacuum packed baconburgers which were allowed to spoil at 5, 10 and 22° was dominated by atypical streptobacteria. Corynebacterium spp., micrococci, Bacillus spp. and lactic acid bacteria survived the post‐packing pasteurization treatments. There was no increase in bacterial numbers in 3 weeks at 5°, but at 10 and 22° group D streptococci grew and caused a souring spoilage of the product. Sodium metabisulphite, added to an initial level of 300 p/m SO 2 retarded the growth of organisms, but had no qualitative effect on the flora. Of the two methods for extending the shelf life of vacuum packed baconburgers, the addition of SO 2 was the safer, as the public health significance of group D streptococci is at present decidedly equivocal.