Accelerated postmortem aging of beef utilizing electron-beam irradiation and modified atmosphere packaging

The combined effects of electron-beam irradiation and modified atmosphere packaging (MAP) with 25% CO2 and 75% N-2 were examined. Steaks from prerigor beef longissimus (lumborum and thoracis) were prepared, placed in MAP, irradiated with 2 kGy, and stored at 15 degrees C or 30 degrees C. Postrigor longissimus steaks from the other half of each carcass were vacuum-packaged and stored at 2 degrees C. Analysis for tenderness, lipid oxidation, color, and microbial growth were conducted over 2 wk. Aging irradiated prerigor beef at 30 degrees C for 2 days with MAP resulted in similar Warner-Bratzler shear values as conventional wet aging at 2 degrees C for 7 or 14 days, and steaks did not show discoloration, lipid oxidation, or microbial spoilage.