High-pressure processing and storage temperature on Listeria monocytogenes, microbial counts and oxidative changes of two traditional dry-cured meat products

Abstract

The effects of high hydrostatic pressure (HHP) processing (600 MPa, 8 min, 16 °C) and storage temperature (4 °C and 18 °C) on experimentally inoculated Listeria monocytogenes (L. monocytogenes), mesophilic aerobic plate counts (APC) and yeast and mould (YM) populations in Iberian dry-cured “salchichón” (DCS) and dry-cured loin (DCL) during 120 days of storage were studied. Tocopherol contents, fatty acid profile, instrumental colour and lipid and protein oxidation were evaluated. HHP treatment reduced L. monocytogenes population by >3 log10 in both DCS and DCL. HHP and storage temperature affected APC differently in both products, whereas YM were significantly decreased by HHP, mostly at 18 °C. Lipid and protein oxidation were promoted, mainly in DCS, and the colour was affected in a minor extent. Despite these effects on oxidation, these results suggest that HHP treatment at 600 MPa for 8 min in both products allowed to control L. monocytogenes below the microbiological limit established by the food safety regulations.