Method 1: Check the sales deadline.
1. Raw fish refrigerated for more than 2 days before the sales deadline must be thrown away. Raw fish can't be refrigerated for long. Once the sales deadline is exceeded, the fish will go bad quickly. Check the sales deadline on the package. If the sales deadline of 1 or 2 days has passed, then throw away the fish! If you want to extend the shelf life of fish, you must freeze them.
If the date of consumption is printed on the fish package instead of the date of sale, then the preservation time of the fish should try not to exceed the previous date. "Expiration date" means that if you don't eat fish on this day, the fish will start to go bad.
2. Cooked fish can be kept in the refrigerator for 5 to 6 days, which exceeds the sales period. If you buy cooked fish, or cook it after you buy it, be sure to put the fish in a sealed fresh-keeping box and refrigerate it in the refrigerator. This kind of treated fish can last longer than raw fish. However, if the fish has not been eaten five to six days after the sales deadline, the remaining fish must still be thrown away. If you know in advance that you can't finish the fish before it expires, put the fish in the frozen area to extend its shelf life.
If you plan to cook the fish and put it in the refrigerator, and then throw away the original packaging bag, be sure to write down the sales deadline so as not to forget.
You can write down the sales deadline on the post-it note and stick it on the fish crisper. You can also put post-it notes on the refrigerator door.
3. Fish beyond the sales period can be frozen for 6 to 9 months. Whether cooked fish or raw fish, the fresh-keeping time of the former is much longer than that of cold storage. But smoked salmon is the only exception. Even if it is frozen, smoked salmon can only be kept for 3 to 6 months at most. Whether the salmon you buy is raw or cooked, it can be frozen. Wrap the fish with plastic wrap or put it in a sealed box before freezing.
Method 2: Check the fish.
1, feel whether there is sticky feeling on the surface of raw fish. As time goes on, fish will start to go bad. Fish's skin will get wetter and wetter, and eventually it will secrete a thin layer of mucus. When these changes occur, there is no doubt that the fish must have gone bad. Once the fish is thoroughly deteriorated, the mucus on the surface of the fish will become more and smoother. Once the surface of fresh fish becomes sticky and slippery, it must be thrown away immediately.
Cooked fish will not feel sticky even if it goes bad.
2. Smell the fish for strong fishy smell. Both cooked and raw fish smell of fish. However, when the chilled fish begins to deteriorate, the fishy smell will get stronger and stronger. A little longer, this strong fishy smell will even turn into a disgusting carrion smell. As the fish slowly rots, the fishy smell will get stronger and stronger. When the fish starts to smell uncomfortable, throw it away!
3. Check whether the raw fish turns milky white. Normal fish is pale pink or white with a transparent liquid on its surface. With the storage time getting longer and longer, fresh fish or frozen fish will deteriorate, and the surface of meat will become more shiny and milky white. The milky white part may have a little blue or gray. Cooked fish will not turn milky white. The above signs of fish deterioration will only appear on raw fish.
4. Check the fish for signs of freezing. Frozen for more than 9 months, fish will show signs of freezing and burning. Pay attention to whether there are prominent ice crystals and discolored patches on the surface of fish. It's best to throw away food that shows signs of freezing. Frozen food can still be eaten in theory, and it won't make people sick. However, the fish will lose its original fresh taste and become dry and firewood.
Method 3: Identify expired salmon.
1, pay attention to whether the white line on the salmon fish is still there. These white lines divide the fish into pieces, which is the most obvious difference between salmon and other fish. If the white line disappears or the color is gray, it means that the fish may have gone bad.
2. Press the fish with your fingers to see if it is tight. Fresh salmon suitable for eating has a firm and firm feel. If the salmon in the refrigerator becomes soft and crisp, it means that this fish is likely to be out of date. The white line between meat slices not only indicates the freshness of fish, but also relates to the compactness of fish. When the white line becomes blurred, the fish must feel soft and sticky.
3. Check the salmon for spots. Unlike other fish, when salmon begins to go bad, the color of fish will change. Most fresh salmon are pink. If you see some abnormal spots on the surface of the fish, the fish may have gone bad. Most of the spots are dark. Some salmon will also have small white spots after deterioration.
Tip: Canned fish won't go bad for years. Canned tuna, anchovies or sardines can still be eaten even after the sales period of 2 to 5 years. But if the canned fish is stored for more than 5 years, you'd better throw it away.
If there is only a shelf life on the canned salmon, but there is no shelf life, you should eat the fish before the shelf life comes.
Canned salmon expires faster than other canned fish, so canned salmon must be eaten after 6 to 9 months.
Warning If you suspect that the fish is bad, throw it away. If you get food poisoning after eating it, it's not worthwhile.