Inoculated ground beef was stored at –22 °C for 5 and 75 days.
After thawing at 4 °C/16 h, 20 °C/12 h, in microwave/22–24 min, or without prior thawing, beef patties (90 g) were shaped and cooked in oven-broiler or in pan-grill to internal temperatures of 60 °C or 71 °C.