Efficacy of different storage practices in maintaining the physicochemical and microbiological properties of fresh pork sausage

Fresh pork sausages, overwrapped with oxygen-permeable films or packed under modified atmosphere (MAP; 65% O-2 and 35% CO2), immediately after production or after 1-day storage at 0C, were stored either at 2C in a domestic refrigerator or at 5C in a refrigerated display cabinet beyond the commercial terms. pH, A(w), lipid oxidation, color and microbial counts were evaluated during storage (3, 6 and 9 days for overwrapped and 6, 12 and 15 days for both MAP practices). pH showed a significant decrease in all packed samples, especially at 5C. Lipid oxidation slightly increased in all sausages and more markedly under high O-2 concentrations of MAP. Discoloration (a*) was noticed in all samples, both in the external and internal surfaces, more clearly under light exposure of the cabinet. Spoilage bacteria increased under both packaging conditions and more markedly at 5C. A shelf-life extension beyond the commercial term of 6 days might be considered only for oxygen-permeable film packaging. On the contrary, it seems difficult to maintain pork sausage quality up to 12 days (commercial term) and beyond under the high O-2 concentrations of MAP.