Microbial and chemical spoilage of chicken meat during storage at isothermal and fluctuation temperature under aerobic conditions

Microbial activity and spoilage of chicken meat from the market in Mashhad, Iran, stored in air at 0, 4, 10 and 15°C was assessed. Microbial spoilage population, Total VolatileBase Nitrogen (TVB-N), pH and organoleptic changes were determined. Based on the results of sensory analysis, shelf-life of chicken meat stored at 0, 4, 10 and 15°C was 72, 120, 220 and 320 h, respectively. TVB-N that serves as an important indicator increased with storage time and TVB-N values were more than 28 mg/100g at the time of unacceptable sensory analysis. Both of them showed a high correlation coefficient with microbial growth, especially, Pseudomonas spp. However, pH cannot be used as a good indicator of chicken spoilage under aerobic conditions and there was relatively low correlation between this parameter and the sensory analysis. The results from microbiological behavior analysis, organoleptic quality and TVB-N values
identified pseudomonas spp. as special spoilage organisms (SSO) of poultry meat stored at 0-15°C and Pseudomonas spp. population level was 7.5 CFU/g at the end of shelf life. The microbial growth under dynamic temperature condition followed the same pattern and the results showed that temperature abuse affects the surviving population of Pseudomonas spp. and it leads to reduction of shelf life.