Every angler knows that fish is at its best when it’s as fresh as possible, and nothing beats the flavor you get when you dispatch, clean, and cook your catch immediately.
But that’s not always possible or practical, and storing fish in a livewell, cooler, or refrigerator is common.
As a result, lots of folks want to know how long you can keep dead fish before they go bad.
The short answer is not long, though the time varies by species, preparation, and temperature.
If you want a clear, simple, science-based answer, keep reading!
Table of Contents (clickable)
How Long Can Dead Fish Last Before They Spoil?
Three variables determine this:
- gutting, and
Let’s break each of these variables down to better understand how long dead fish can be safely stored.
The fattier the flesh and the colder the water, the faster the spoilage.
Salmon spoil faster than croaker, and croaker spoil faster than bass.
This results from differences in the amount of easily spoiled fat and the temperature range usual for that species.
Higher fat content means more enzymatic decomposition, and lower water temperatures make slowing that process much more difficult.
Removing the guts of a fish will slow decomposition by removing sources of bacteria that start and speed up the decay process.
For saltwater species, bleeding can also help preserve the flesh longer.
Here's our top recommendation for fillet knives: Best Fillet Knives For Anglers
And for saltwater fish: Best Fillet Knives For Saltwater Fish
Simply put, the colder you keep your fish, the longer they last.
As a general rule, properly chilled fish can last as long as 1 to 2 days ungutted, or 4 to 5 days with the guts removed (and bled, if appropriate).
To me, these are absolute maximum time frames, and it’s always best to clean and cook fish well within those numbers.
Why Does Fish Spoil Faster Than Meat?
If you’re a hunter as well as an angler, you probably know that your kill can stay fresh on ice for some time with no risk of spoilage. In fact, I usually leave my freshly butchered venison in a bath of ice, salt, and water overnight to help bleed the meat and improve its flavor.
But fish is a different story, and science explains why.
Terrestrial critters like deer, pigs, sheep, and cows walk around with body temperatures that are remarkably high.
Cows, for instance, have a normal body temp of 100 to 102.5 degrees!
The bacteria and enzymes in beef are evolved for these high temperatures, and storing fresh steaks or chops on ice slows their decomposition process to almost nothing.
But most fish are cold-blooded, meaning that they don’t regulate their own body temperature. Instead, they operate at the temp of the surrounding water. For most species, that’s pretty cool, and ice doesn’t work nearly as well to stop decomposition.
Experts like Harold McGee put it this way, “The microbes and body enzymes of cattle, pigs and chickens are accustomed to operating above 90 degrees. In a typical refrigerator at 40 degrees, they're nearly paralyzed. But the bacteria and enzymes of many ocean fish feel right at home and happily proceed to break apart the fish's proteins and fats into smaller, smellier molecules. The spoilage agents in warm-water fish do feel chilled and slow down -- somewhat.”
Ice, Ice, Baby!
As the fats begin to break down in fish, they’ll take on a characteristically foul, ammoniated smell. Other signs of spoilage include cloudy eyes, pale gills, and flesh that remains dented when you press it.
The only way to slow that process is to keep your fish very, very cold.
I don’t mean refrigerator cold; I mean carefully iced and as cold as you can.
If you want your fish to last 1 to 2 days ungutted, or 4 to 5 days gutted and bled, you need to ice them properly.
There’s not nearly enough ice to keep these fish fresh, as you can already see from their cloudy eyes.
At the very least, they need to be kept in a cooler filled with ice. Keep the lid closed unless absolutely necessary, and ensure that the fish are covered in ice. The drain plug should be open to let water leave the cooler, and ice should be added frequently to keep your catch as cold as possible.
This is proper icing to prevent spoilage.
The anglers at Mossy Oak recommend that “two pounds of ice should be added for every pound of fish. Fish and ice should be mixed as evenly as possible in the cooler.”
- Lots of ice, changed frequently.
- Drain plug open, no water.
- Keep the lid closed.
- Keep the fish covered in ice.
Even the best cooler isn’t the best way to store fish before you clean and cook it.
Instead, the best way is to use your refrigerator and a careful system of icing.
- Rinse your fish in cool water and dry them thoroughly with paper towels.
- Wrap your fish in cling wrap. You want to avoid direct contact with the ice and seal off your fish from oxygen.
- Place plenty of crushed ice in a shallow pan.
- Place the fish on the crushed ice and cover with a thin layer of ice, surrounding the fish entirely.
Most anglers don’t go to this trouble, but doing so will keep your fish fresh for as long as possible.
Line to pan is always the best, but not always possible. And when you need to keep fish fresh before you can clean and cook it, the best advice is to use lots and lots of crushed ice.
Even then, some species just can’t take the heat and will spoil quickly.
We hope that you’ve learned something from this article, and if you have any questions, we’re happy to take a shot at an answer!