Effect of gamma irradiation on shelf life of smoked guinea fowl (Numida meleagris) meat stored at refrigeration temperature

Abstract

This study investigated the effect of gamma irradiation on shelf life of smoked guinea fowl meat stored at refrigerated temperature. Dressed guinea fowl meats were smoked, packaged and gamma irradiated at 2.5, 5.0 and 7.5 kGy with a dose rate of 0.74 kGy h−1 and compared with a control (un-irradiated). Physicochemical, sensory and microbial properties of the treated meats were determined over refrigerated storage period using appropriate procedures. Titratable acidity (TA) and acid value (AV) decreased significantly (p ≤ 0.05) with gamma irradiation, but increased with storage. pH of the meat samples were however within the neutral range which was numerically insignificant to affect quality characteristics of the processed meat. Bacterial isolates of natural microbiota identified on the basis of their mass spectra of protein profiles on the smoked guinea fowl meat were Staphylococcus aureus, Serratia marcescens and Enterobacter cloacae. The total bacterial counts (7.23 log10 cfu/g) decreased with increasing doses of gamma irradiation and storage (1.29 log10 cfu/g). Irradiation had highly significant effects (p ≤ 0.05) on the reduction of microbial population. Irradiation had no significant effects (p > 0.05) on the sensory attributes (aroma, colour, tenderness and taste) of the smoked guinea fowl meat; but the taste of the irradiated meat samples was influenced at the end of the seven weeks refrigerated storage period. Gamma irradiation has a potential to enhance shelf life of smoked guinea fowl meat at a refrigeration condition.