Microflora and color of ground beef in gas exchange modified atmosphere packaging with abusive display temperatures

Gas exchange modified atmosphere packaging (GEMAP) with display gas of 80% O-2:20% CO2 retarded microbial growth and improved color stability of ground beef patties compared with vacuum packaging (VP) followed by air-permeable polyvinylchlorlde (PVC) overwrapping during 3 d of retail display. Predominant microorganisms for GEMAP were Pseudomonas, Yersinia, Aeromonas, and Enterobacter and for VP-PVC were Pseudomonas, Brochothrix, Aeromonas, Enterobacter, Moraxella, and Lactobacillus. Lower levels of pathogens were isolated in GEMAP samples with 7 degreesC than 15 degreesC display temperature. Patties were darker (lower L*) with those with 15 degreesC than with 7 degreesC display and redder (higher a*) in GEMAP than VP-PVC. Good manufacturing practices should be followed with MAP meat to reduce the risk of pathogenic microbial growth.