If you go to the market looking to buy fish, the main concern you might have is how you can tell if a fish is fresh. Seafood such as fish can very quickly go bad, and the quality deteriorates quite sharply the moment it stops being fresh. Thus, it is quite important to know what to look for in fresh fish.
Look at the eyes
The first and best sign to look for in fresh fish is the eyes. The eyes should be clear and bulging out slightly, rather than dull and swollen.
Look at the gills
The next sign to look for is the gills. If the gills are healthy, they would be bright red and a bit wet. In contrast, fish that are not so fresh would have gills that are brown or a faded dark red. This is almost similar to checking for freshness in a cut of red meat. Also, if there is a milky liquid around the gills, it means the fish has already started to rot.
Look at the skin
Fresh fish will have shiny scales covering its body. Just like its eyes, the shine on the scales will fade the longer the fish is exposed to the air.
Sniff the body
This may be a bit of a risk to your sense of smell, but if you have some confidence in the freshness of the fish and just needed a quick confirmation, smell the fish. If you have a fresh fish in your hands, you will find that the typical fishy smell does not come from them; fresh fish should only smell of the water they came from, be it freshwater or saltwater.
Touch the flesh
If you’re dealing with fillets or cuts of fish where you are not able to observe any of the above, one thing you can do to confirm the freshness of the fish is to gently press down into the flesh, and then quickly lift your finger off the fish. If the mark from your finger disappears quickly, that means the flesh is still quite bouncy and fresh, whereas if the mark from your finger stays for a while, it means the flesh is no longer fresh.
Fresh vs Frozen
You might want to consider purchasing frozen fish, depending on where you live. If you are living in cities close to fishing ports, such as Klang, then you should buy fresh fish. But if you live in cities that rely on transporting fishes caught on the coasts, then the better option is to buy frozen fish because fishes transported into your area would not have survived the journey intact, so they may have already been frozen anyway.