Salt fish is fresh fish that has been preserved through heavy salting and drying, a method that draws moisture out of the flesh to prevent spoilage. Cod is the most common species used, which is why “salt fish” and “salt cod” are often used interchangeably, but the term can also apply to other white fish like pollock and hake. It remains a staple ingredient in Caribbean, Portuguese, West African, and Mediterranean cooking.
How Salt Fish Is Made
Fresh fish flesh contains 75 to 80 percent water. During the curing process, food-grade salt is packed onto or around the fish, pulling that water out and replacing it with salt. Once the salt concentration in the fish tissue reaches 6 to 10 percent and enough moisture has been lost, most spoilage bacteria can no longer grow. That’s the entire principle behind it: remove the water, and the fish stops rotting.
There are three main methods. Dry salting involves packing layers of salt directly onto the fish fillets and stacking them so the liquid drains away under gravity. Wet salting, or brining, submerges the fish in a concentrated salt-and-water solution. Some producers use a combination, brining first and then dry-salting to finish. After salting, the fish is typically dried in open air, sometimes on wooden racks, until it becomes stiff and board-like. The finished product has a water content as low as 15 to 20 percent, which is why a piece of salt fish feels hard and almost woody to the touch.
A History Stretching Back Over a Thousand Years
Salting fish is one of the oldest preservation methods in the world, but the technique took off in a major way with the Vikings. In the late eighth or ninth century, as Viking shipbuilders developed keeled longships capable of crossing rough open water, crews needed food that wouldn’t spoil on long voyages. They would slice open cod, remove the spine and innards, and dry it on rocks or wooden racks along the shore. The resulting product, called stockfish, was so hard and dry it earned the name “stick-fish.” The earliest written reference appears in Egil’s Saga, with a manuscript dating to around 1240, describing stockfish being brought from Norway to Iceland in 875. Leif Erikson reportedly carried a supply to Newfoundland around the year 1001.
The Basques adopted the technique around the same time and began adding salt to the drying process, which produced a more versatile product that European markets eagerly consumed. By the 1500s and 1600s, salt cod had become a cornerstone of Atlantic trade. English fishermen were salting 150 shiploads a year for the European market by 1660, and fishing stations sprang up along the New England coast, with more than half a dozen “cod” settlements founded in Massachusetts alone. The Caribbean sugar boom of the late seventeenth century supercharged demand even further: plantation owners needed cheap, durable protein to feed enslaved workers, and salt fish fit the bill perfectly. That connection is a large part of why salt fish remains so central to Caribbean cuisine today.
Where Salt Fish Shows Up in Cooking
In Portugal, salt cod (bacalhau) is so deeply embedded in the food culture that the word “cod” almost always refers to the salted, dried version rather than fresh fish. The Portuguese claim to have over a thousand recipes for it, from creamy gratins to fried fritters called pastéis de bacalhau.
In Jamaica and across the Caribbean, ackee and saltfish is the national dish, typically served for breakfast alongside fried dumplings, boiled green bananas, or yam. The fish is also stir-fried with peppers and onions and served with “bakes” (fried bread) in Trinidad. In southern France, brandade de morue blends rehydrated salt cod with olive oil and sometimes potatoes into a smooth, rich spread. Variations appear in Spanish, Italian, Brazilian, and West African kitchens as well, each shaped by the local ingredients and spices available.
How to Prepare Salt Fish Before Cooking
You cannot cook salt fish straight from the package. It needs to be desalted and rehydrated first, and the time this takes depends entirely on how thick the piece is. Plan ahead.
Start by rinsing the fish under cold running water to remove the heavy outer layer of salt. Then place it skin-side up in a large bowl of cold water and refrigerate it. From here, the process is mostly about patience and water changes:
- Small dried pieces (sold in 400 to 500 gram packs): 6 to 8 hours, changing the water every hour.
- Thin cuts like tails, wings, or small loins: 12 to 24 hours with at least 2 water changes.
- Medium center-cut loins: 24 to 36 hours with 4 water changes.
- Thick center-cut loins: 48 to 55 hours with 6 water changes.
- Extra-thick jumbo loins (from fish over 3 kilograms): up to 72 hours, changing water every 6 to 8 hours.
Keep the bowl in the refrigerator the entire time, ideally between 3°C and 5°C (37°F to 40°F). Once it’s fully soaked, the fish should feel plump and flexible, closer in texture to fresh fish. If you taste a small piece and it’s still unpleasantly salty, give it a few more hours with fresh water.
Nutrition and Sodium Considerations
Salt fish is a high-protein, low-fat food, which is part of why it became such a practical staple for working populations over the centuries. However, even after soaking and rinsing, it retains significantly more sodium than fresh fish. The World Health Organization recommends adults consume less than 2,000 milligrams of sodium per day, roughly equivalent to one teaspoon of salt. A single generous serving of inadequately soaked salt fish can approach or exceed that limit on its own. Thorough desalting makes a real difference, and if you’re watching your sodium intake, longer soaking with more water changes is the simplest way to bring the levels down.
Storage and Shelf Life
One of salt fish’s greatest advantages is its longevity. Properly dried and cured salt cod is commonly labeled with a shelf life of one year when stored at or below 4°C (about 40°F). In practice, the salt content and low moisture keep it safe well beyond what fresh fish could manage, which is exactly why the preservation method was developed in the first place. Store it in a cool, dry place, and keep it wrapped or sealed to prevent it from absorbing other odors.
Once you’ve rehydrated salt fish, treat it like any fresh seafood. Use it within two to three days and keep it refrigerated. You can also rehydrate a larger batch and freeze portions for later use, which saves the hassle of repeating the multi-day soaking process each time you want to cook with it.