Porosity in cooked beef from controlled atmosphere packaging is caused by rapid CO2 gas evolution

Meat packaged and stored in CO2 atmospheres (O-2 < 200 ppm) develops pores during cooking. Packaging beef in CO2 or 0.25 M NaHCO3 (pH 5.6) duplicated pore formation. Beef stored in vacuum-packaging following storage in CO2 exhibited pores after cooking. Dialysis with distilled water eliminated pore formation and reduced gas production during cooking of beef stored in 0.25 M NaHCO3 or CO2. Differential scanning calorimetry showed that the thermal denaturation temperature of purified collagen was not affected by CO2 storage. These data suggest that pore formation is linked to release of CO2 in meat during cooking. Cooking denatures proteins; thus, CO2 released during cooking may gather at the weakest point of the muscle, the perimysium, producing pores. Copyright (C) 1996 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd