Checking fish for freshness matters for both flavor and food safety. Eating spoiled fish can pose health risks, so use a few simple checks when shopping. Freshness is generally assessed by sight and touch; these signs show freshness, but they do not replace keeping fish cold and cooking it properly. Here is what to look at, what to look for when buying fish, and how to store it after bringing it home.
Check the Eyes and Skin
One of the most noticeable signs of fresh fish is its eyes: they should be bright and slightly convex. As fish loses freshness, the eyes become dull and sunken. The skin also offers clues; fresh fish has taut, shiny skin. If you press it lightly with a finger, the indentation should spring back right away. On stale fish, the mark may remain for a while. Dull, sponge-like skin can also indicate reduced freshness.
Check the Gills and Tail
Fresh fish has vivid red gills; ask the fishmonger whether you can look at them. On stale fish, the color fades toward brown or gray. Another suggested check is to lift the fish by its head: the tail of fresh fish stays upright, while the tail of stale fish droops. This is easiest where customers are allowed to handle the fish.
Check the Scales and Smell
Fresh fish scales should cling firmly to the body rather than fall off. Scales that come away easily or are scattered on the counter may indicate that the fish has been sitting for a while. Fresh fish should have little odor, perhaps a mild scent of the sea. A strong, heavy, ammonia-like smell is a clear warning sign; do not buy fish that smells this way.
What to Look for When Buying Fish
Choosing fish displayed neatly on ice and avoiding fish that are piled up or crushed, since their quality may deteriorate more quickly is recommended. Ask the fishmonger if you may check the gills and eyes. For fillets, look for flesh that is bright and firm, with edges that are not dried out. A yellowish film or dull appearance may indicate that a fillet has been sitting for a while.
How to Store Fish at Home
Refrigerate fish as soon as possible after bringing it home; a long trip can reduce freshness quickly. Keep fish in the coldest part of the refrigerator, at 4°C / 39°F or below, buried in ice or with ice placed over it. If you will not cook it that day, freezing it is described as the safest option. Freezing fish in an airtight bag can help preserve freshness and texture. Thaw frozen fish slowly in the refrigerator, not at room temperature; rapid thawing can damage its texture.
How to Tell Whether Fish Was Frozen and Thawed
Some fish displayed as fresh at a market may have arrived frozen and then been thawed. Compared with fresh fish, thawed fish may look looser and wetter, and an indentation from pressing it may take longer to disappear. A pinkish liquid under the fish may indicate moisture loss during freezing and thawing; fresh fish would not have this pooling. Thawed fish may still taste good, but if it costs the same as fresh fish, ask about its handling history before buying.