The Doppler Effect Flow meter uses reflected ultrasonic sound waves to measure the velocity of particles in the fluid. By measuring the frequency shift between the ultrasonic frequency source, the fluid carrier, and the receiver, the relative fluid velocity is measured.
How long it took to freeze will have a bearing on it, too. If the ground beef was 3 days old when frozen, you might try cooking it from frozen. If it was freshly ground when frozen, the thawed meat will likely be good for 2 days. Once thawed, the ground meat should be used within a day or two. Ground meat spoils quickly since grinding the meat mixes bacteria throughout.
In the Refrigerator. Once frozen lamb has thawed in the refrigerator, roasts, steaks and chops can be stored safely in the refrigerator for 3 to 5 days and ground lamb will be safe for 1 to 2 days. If you decide not to use it during this time period, you may refreeze lamb without cooking it first.