Vacuum-packaged beef trimmings were stored for four time periods of 0, 1, 2 and 3 wk (4 lots) at 5°C. After the storage period, the four lots of trimmings were evaluated for chemical, microbial and sensory properties. Each lot was then made into beef patties. Two lots of patties (0 and t wk of storage at 5°C) were further stored at −18°C for 0, 3, 6, 9 and 12 months and used to determine sensory properties. The two lots prepared from trimmings stored for 2 and 3 wk were evaluated for chemical properties at 0, 6, 9 and 12 months of −18°C frozen storage. Patties prepared from vacuum-packaged beef trimmings stored for 2 and 3 wk had significantly lower sensory ratings as compared to ratings for patties made from trimmings stored for 0 or 1 wk. Microbial counts indicated that bacterial action could be more important than oxidative rancidity as the cause for these changes. Increased length of frozen storage time did not markedly affect sensory properties.