Shelf-life extension and colour stabilisation of beef packaged in a low O2 atmosphere containing CO:: Loin steaks and ground meat

A combination of low O-2, high CO2 and very low CO was investigated for packaging fresh beefsteaks and ground meal. The following atmospheres were used: 70% O-2 + 20% CO2 + 10% N-2 (CMA); 70% O-2 + 20% CO2 + 9% N-2 + 1% CO (HO-CO) and 24% O-2 + 50% CO2 + 25% N-2 + 1% CO (LO-CO). Bacterial counts showed that LO-CO atmosphere greatly reduced psychrotrophic population, so that log cfu cm(-2) was under 7.5 at 29 days of storage at 1 degrees C. All the objective measurements related to meat colour (a*, hue, Chroma and metmyoglobin concentration) revealed that the bright-red colour was more stable in both HO-CO and LO-CO atmospheres, reaching 29 days of storage without appreciable signs of oxidation. Sensory analysis confirmed these results. (C) 1997 Elsevier Science Ltd. All rights reserved.