If you let it out at room temperature to defrost, never refreeze it (which you should never do anyway). Even if you thawed the meat in cold water or the microwave, it's not a good idea to refreeze it since both procedures allow germs to develop on sections of the meat that have warmed above refrigerator temperature. Germs can then be transferred to other parts of the meat when they are refrozen. However, if you're in a hurry to get food into the house for your family, then freezing it is an acceptable alternative. That being said, frozen hamburger is not as tasty as fresh hamburger and usually has more fat than straight-from-the-steak hamburger. Frozen meat is available packaged in individual servings or in large quantities that can be sliced as needed. It's best to buy frozen meat in small amounts that will last for several meals so that you don't need to use up all your money on one purchase. Frozen meat contains less bacteria than meat that has not been frozen, which means that it's possible to eat some amount of frozen meat without getting sick. However, you should still always cook it to the proper temperature before eating. Refrigerated or frozen meat should be used within three months. After that time, the quality of the meat begins to suffer. Cooked ground beef can be kept frozen for up to one year.