Effects of High Pressure Processing and Hot Water Pasteurization of Cooked Sausages on Inactivation of Inoculated Listeria monocytogenes, Natural Populations of Lactic Acid Bacteria, Pseudomonas spp., and Coliforms and Their Recovery during Storage at 4 and 10°C

ABSTRACT The study investigated the effects of high pressure processing (HPP; 600 MPa for 3 min) and hot water (HW; 75°C for 15 min) pasteurization on the inactivation of inoculated Listeria monocytogenes, natural populations of lactic acid bacteria, Pseudomonas spp., and coliforms in vacuum-packaged cooked sausages and their recovery during storage at 4 and 10°C for 35 days. Cooking sausages to an internal temperature of 72°C resulted in a >6-log reduction in numbers of inoculated L. monocytogenes. Storage at 4°C resulted in no significant difference (P > 0.05) in L. monocytogenes numbers in sausages pasteurized by either HPP or HW compared with unpasteurized control. However, at 10°C, L. monocytogenes numbers in unpasteurized control sausages increased to about 7 log CFU/g by day 35, whereas in HPP-pasteurized sausages, numbers remained below the detection limit for up to 21 days and then increased to 4.5 log CFU/g by day 35. HW pasteurization resulted in inhibition of L monocytogenes to below the detec...