Effects of modified atmosphere packaging on an extended-spectrum beta-lactamase–producing Escherichia coli, the microflora, and shelf life of chicken meat

The effects of modified atmosphere packaging on an extended-spectrum beta-lactamase–producing Escherichia coli strain and product quality characteristics of skinless chicken meat were determined. The samples were packed separately in air, 100% N(2), and prefabricated gas mixtures with 75% O(2) + 25% CO(2) and 70% CO(2) + 15% O(2) + 15% N(2) and incubated at 3°C for 7 d. To investigate the influence of the headspace ratio, samples were packed in identical trays to 600 g and 120 g. After 0, 2, 5, and 7 d of incubation, the samples were analyzed microbiologically and photometrically, and pH was measured. The results show that the development of the microorganisms depends on the atmosphere, with the 70% CO(2) + 15% O(2) + 15% N(2) atmosphere having the highest development-inhibiting effect. This effect is increased with increased headspace. No significant effects on the pH and color of the samples were observed.