Improving the hygienic quality of chicken through radiation processing

Irradiation is considered one of the most efficient technological processes for the reduction of microorganisms in food, It can be used to improve the safety of food products, and to extend their shelf lives. The aim of this study was to improve the hygienic quality of chicken through radiation processing. As part of the study a microbial assessment of broiler chicken thighs from three retail outlets (supermarket, local markets and farms) was conducted. The total viable count and total coliform counts were determined. Hygienic quality indicator organisms such as Escherichia coli, Salmonella and Staphylococcus aureus were isolated and microbial counts made. Radiation sensitivity test to determine the D10 (decimal reduction does) of E. coli on chicken at refrigeration and frozen temperature were conducted. D10 values were 0.22 ± 0.02 and 0.32 ± 0.03 kGy at refrigerated and frozen temperatures respectively. A storage test consisting of an uninoculated pack experiment and a challenge test to explore the effect of irradiation and frozen food storage on the total viable count and survival of E. coli was conducted. Chicken thigh samples were treated with 0 (non irradiated), 2.0, 4.0, 6.0 and 8.0 kGy of gamma irradiation and held frozen for 56 days. The control and irradiated samples were stored at -18 oC and underwent microbial analysis and sensory evaluation at 7 days intervals. It was observed that irradiation and frozen storage reduced microbial loads. There were significant differences in sensory quality characteristics during freezing storage in chicken meat. The combination of irradiation and frozen storage resulted in greater overall reductions on microbial loads thus improving hygienic quality. (au)