Final answer:
Refrigerated ground beef must be kept at or below 4°C (40°F), and when cooked, must reach a safe internal temperature of at least 71°C (160°F) to ensure safety. Always use a food thermometer to check temperatures.
Step-by-step explanation:
The coldest temperature that ground beef must reach before it can be served varies depending on whether the meat is to be cooked or kept refrigerated for later use. For refrigerated ground beef that is stored before cooking, the temperature must be kept at or below 4 degrees C (40 degrees F) to prevent bacterial growth. However, when cooking ground beef, it must reach a safe internal temperature of at least 71 degrees C (160 degrees F) to ensure it is safe for consumption as per USDA guidelines. Using a food thermometer is the best way to ensure that ground beef has reached the necessary temperature to kill any bacteria it contains. It is important not to consume the beef if it has been in the danger zone of 4 to 60 degrees C (40 to 140 degrees F) for more than two hours due to the risk of bacterial growth.