Throw Your Packaged Frozen Fish Away Immediately If You Notice This
There are plenty of reasons to purchase frozen fish over fresh fish. The most obvious is its longevity; frozen fish can last up to a year in the freezer, according to the USDA, while fresh fish must be consumed within a matter of days. And when it comes to cost, frozen fish tend to be less expensive, as per Health.
Those who want to save money might opt for the frozen kind, especially if they're not sure they'll use the fillets quickly. With fresh fish, it's relatively easy to tell when it's past its prime — a slimy texture and strong odor are significant indicators, according to EatByDate. On the other hand, frozen fish doesn't quite exhibit the same traits when it has gone bad. Instead, there is one other sign you should keep an eye on, which will immediately tell you if the fish is too old or potentially unsafe to eat.
Throw away your fish if you notice any ice crystals
When you purchase frozen fish in the grocery store, it should be clean looking. Meaning, you can clearly see the fish in its packaging, and it's not coated with ice crystals. And if there are any ice crystals on the product, discard it immediately. Those tiny crystals are a big sign that the fish could make you sick.
Best Life says that ice crystals on frozen seafood indicate that the fish was, at one time, exposed to temperatures below freezing. If the fish was thawed and refrozen, those crystals can form from the moisture released during the thawing process. It's a sign that the fish might have reached a temperature that allowed for bacteria growth. And since you can't know for how long the fish was at that temperature, it's best not to consume it.
The ice crystals might also mean the fish has freezer burn, which is a sign that it's been sitting frozen for far too long, which can affect its texture and quality. Frozen food doesn't necessarily expire, so freezer burn won't make you sick, but it could mean the fish will have a wonky flavor. Either way, ice crystals are a strong sign that the fish isn't suitable for consumption.