Retail-packed rump (Gluteus medius, GM) and striploins (Longissiumus dorsi, LD) steaks were masterpackaged under carbon dioxide (CO2) and stored at 1 °C ± 1 °C for 14, 28, 35, and 42 d. A commercial oxygen (O2) scavenger (ATCO HV1000®, Standa Industrie, Caen, France) was used in the masterpacks to achieve an O2-free atmosphere. Similar packages without the O2 scavengers were also prepared. At each storage time, 2 masterpacks of each treatment were opened and the retail trays were placed in a display case at 4 °C ± 2 °C for 1 and 48 h for microbiological and sensorial evaluations. The low growth rate of aerobic psychrotrophic flora on the stored beefsteaks demonstrated the bacteriostatic effect of CO2 during storage. The maximum level of psychrotrophic aerobic bacteria reached during storage was approximately 106 CFU/g. The steaks stored in masterpacks with scavengers bloomed to the desirable red color associated with freshly cut meat in the display case for all of the storage periods, except in the case of GM steaks, which showed a cycle of transient discoloration. GM and LD steaks were well accepted (65% and 82%, respectively) after 42 d under CO2 at 1 °C ± 1 °C. The GM and LD steaks stored without the O2 scavenger showed variable fractions of discoloration that significantly detracted from the appearance of the samples. © 2006 Institute of Food Technologists.