Page 3: What is the best way to thaw ground
The best way to safely thaw
ground beef is in the refrigerator. Keeping meat cold while it is defrosting is
essential to prevent growth of bacteria. Cook or refreeze it within 1 or 2 days.
To defrost ground beef more rapidly, you can defrost in the microwave oven or in
cold water. If using the microwave, cook the ground beef immediately because
some areas may begin to cook during the defrosting. To defrost in cold water,
put the meat in a watertight plastic bag and submerge. Change the water every 30
minutes. Cook immediately. Do not refreeze ground meat thawed in cold water or
in the microwave oven.
Never leave ground beef or any perishable food out at room temperature for more
than 2 hours.
Is it dangerous to eat raw or undercooked ground beef?
Yes. Raw and undercooked meat may contain
harmful bacteria. USDA recommends not eating or tasting raw or undercooked
ground beef. To be sure all bacteria are destroyed, cook meat loaf, meatballs,
casseroles, and hamburgers to 160 °F. Use a food thermometer to check that they
have reached a safe internal temperature.
Are there people who are more at risk from eating ground beef that is
undercooked or mishandled?
The very young, the very old, and those with
immune systems that have been weakened by cancer, kidney disease, and other
illnesses are most at risk and vulnerable to illnesses associated with
contaminated food. The symptoms of foodborne illness — such as diarrhea or
vomiting, which can cause dehydration — can be very serious. Safe food handling
practices at home or anywhere food is served is especially important for those
in the "at-risk" group.
Are microwaved hamburgers safe?
Yes, if cooked properly to destroy harmful
bacteria. Since microwaves may not cook food as evenly as conventional methods,
covering hamburgers while cooking will help them heat more evenly. Turn each
pattie over and rotate midway through cooking. Allow patties to stand 1 or 2
minutes to complete cooking. Then use a food thermometer to check that the
internal temperature is 160 °F.
Is it safe to partially cook ground beef to use later?
No. Partial cooking of food ahead of time
allows harmful bacteria to survive and multiply to the point that subsequent
cooking cannot destroy them.
Can I refrigerate or freeze leftover cooked hamburgers? How should they be
If ground beef is refrigerated promptly after cooking (within 2 hours; 1 hour if
the temperature is above 90 °F), it can be safely refrigerated for about 3 or 4
days. If frozen, it should keep its quality for about 4 months.
When reheating fully cooked patties or casseroles containing ground beef, be
sure the internal temperature reaches 165 °F or it is hot and steaming.
Why is pre-packaged ground beef red on the outside and sometimes dull,
Oxygen from the air reacts with meat pigments
to form a bright red color which is usually seen on the surface of meat
purchased in the supermarket. The pigment responsible for the red color in meat
is oxymyoglobin, a substance found in all warm-blooded animals. Fresh cut meat
is purplish in color. The interior of the meat may be grayish brown due to lack
of oxygen; however, if all the meat in the package has turned gray or brown, it
may be beginning to spoil.
Why does ground beef release a lot of "juice" while cooking?
In making ground beef, some retail stores grind
the meat while it is still frozen. Ice crystals in the frozen meat break down
the cell walls, permitting the release of meat juices during cooking. The same
thing happens after ground meat is frozen at home.
What causes ground beef patties to shrink while cooking?
All meat will shrink in size and weight during
cooking. The amount of shrinkage will depend on its fat and moisture content,
the temperature at which the meat is cooked, and how long it is cooked.
Basically, the higher the cooking temperature, the greater the shrinkage.
Cooking ground beef at moderate temperatures will reduce shrinkage and help
retain juices and flavor. Overcooking draws out more fat and juices from ground
beef, resulting in a dry, less tasty product.
United States Department of Agriculture
Food Safety and Inspection Service