Effect of high pressure processing and modified atmosphere packaging on the safety and quality of sliced ready-to-eat lacon, a cured-cooked pork meat product

Microbiological and sensory characteristics of sliced lacon, a cured cooked meat product, vacuum-packaged (VP), pressurized at 500 or 600 MPa, and modified atmosphere packaged (MAP), were investigated during storage at 4 degrees C for 120 days. Viable bacterial counts exceeded 10(8) cfu/g in VP and MAP lacon from day 30 while this level was not reached in pressurized lacon until day 90. Pressurization at 500 MPa was the best procedure to control Gram-negative bacteria. During storage the pH value declined by 0.13 units in VP, 0.23 units in MAP, and 0.49 units in pressurized lacon. Primary and secondary lipid oxidation indexes declined during storage, with small differences between treatments. Flavour quality scores for 90-day and 120-day samples averaged 5.63 for VP lacon, 6.51 for MAP lacon, 6.48 for 500 MPa lacon and 5.81 for 600 MPa lacon. Flavour quality correlated negatively with viable bacterial counts, lactic acid bacteria and Gram-negative bacteria. Industrial relevance: Shelf-life of sliced lacon can be prolonged by applying HPP or using MAP. Both procedures showed to be valid in retarding the growth of most microbial groups during the first month of refrigerated storage of sliced lacon. Pressurization was more effective than MAP in preventing the growth of Gram-negative bacteria throughout the 120-day storage period, in particular HPP at 500 MPa. (C) 2014 Elsevier Ltd. All rights reserved.