Shelf-life of sausage patties made from pre-rigor and post-rigor pork under vacuum and modified atmosphere packaging

This study was conducted to determine the effect of pre-rigor (PRR) and post-rigor (POR) pork on the shelf-life of sausage patties stored under six treatments-vacuum (Trt 1), 100% CO2 (Trt 2), Air (Trt 3), 75% Ns + 25% CO2 (Trt 4), 75% N2 + 15% CO2 + 10% O2 (Trt 5) and 75% N2 + 20% CO2 + 5% O2 (Trt 6). Six sows were slaughtered and the meat (PRR and PGR) was ground (0.48 cm), mixed with seasonings and stuffed into casings. Sausage was crust-frozen in a CO2 batch freezer (-70C) and transferred to a blast freezer (-21C) for 10 days. After frozen storage, the sausages were sliced into patties, packaged under six treatments (Trt 1 through Trt 6) and stored at 4C for 14 days. Analyses were conducted at 0, 3, 7, 10 and 14 day intervals. PRR had higher (P≤0.001) TBA value, total bacterial count and lactic acid bacterial count than POR. PRR had higher (P≤0.001) percent OMb, Hunter ‘L’ and ‘a’ values as well as lower (P≤0.001) percent MMb than POR. Trt 2 and Trt 4 gave lower (P≤0.001) TBA values and total bacterial counts, whereas Trt 3, Trt 5, and Trt 6 gave higher (P≤0.001) percent OMb and lower (P≤0.001) percent MMb. Trt 2 and Trt 4 are recommended for shelf-life extension in terms of lipid oxidation and microbial growth. For color shelf-life extension, at 50% MMc level, Trt 3, Trt 5 and Trt 6 are recommended