The shelf life of frozen beef is 2 years, which is lower than-65438 08℃. Frozen pork and poultry meat can be stored for up to 1 year, and beef and mutton can be stored for 2 years. However, it is difficult for household refrigerators to meet this requirement. Refrigerator door switch, sudden power failure.
Delayed startup will change the temperature in the refrigerator and shorten the shelf life. Therefore, even if it is not expired, it is best to eat the frozen meat bought back within 1 month, and the sooner the better.
The refrigerator is not a "safe". Even if the meat frozen for too long has not expired, it will be greatly affected in terms of safety, nutrition and taste. Safety: oxidation reaction accelerates aging. Fan Zhihong, an associate professor at the College of Food Science and Nutritional Engineering of China Agricultural University, said that this kind of meat will not breed a lot of bacteria when it is frozen, but once it is thawed, it will breed bacteria more easily than fresh meat. Therefore, meat should not be frozen again after thawing.
The low temperature in the freezer can prevent bacteria from multiplying, but it can't completely prevent the oxidation of fat and protein, so it can't completely prevent the deterioration of meat quality. Due to the oxidation reaction, the color of lean meat frozen for a long time will gradually change from red to brown, and the fat will gradually turn yellow, which will not only make the flavor worse, but also produce fat oxidation products that accelerate human aging.