High-pressure processing applied to cooked sausages: Bacterial populationsduring chilled storage

Vacuum-packaged cooked sausages were pressurized at 500 MPa for 5 or 15 min at mild temperature (65 degrees C) and later stored at 2 and 8 degrees C f or 18 weeks. Counts of aerobic mesophiles and psychrotrophs, lactic acid ba cteria, enterobacteria, Baird-Parker microbiota, and Listeria spp. were det ermined 1 day and 3, 6, 9, 12, 15, and is weeks after treatment and compare d with those of cooked sausages treated at 80 to 85 degrees C for 40 min. P ressurization generated reductions of about 4 log CFU/g in psychrotrophs an d lactic acid bacteria. Enterobacteria and Listeria proved the most pressur e sensitive; insignificant or no growth was detected throughout the study. Heat treatment inactivated psychrotrophs and enterobacteria similarly to pr essure treatment. Listeria monocytogenes and enterotoxigenic Staphylococcus aureus were not found in treated samples. In general, there was no signifi cant difference in counts of any bacterial populations either among treatme nts or between storage temperatures. High-pressure processing at mild tempe rature is an effective preservation method that can replace heat pasteuriza tion applied to some cooked meat and poultry products after packaging.