Summary: Desalting cod requires soaking it in cold water in the refrigerator for 24-72 hours, changing the water every 8 hours to prevent fermentation. Rinse off the excess salt under running water, place the cod skin-side up in a large bowl, and use about 3 liters of water per kilogram of fish. At Bacalalo, we've been answering this question since 1990 at the Mercat del Ninot in Barcelona: the honest answer is that quality cod deserves time, but there's also a 4-6 hour express method that, if done correctly, yields very acceptable results.
Content
- Key steps for desalting cod
- Desalting times according to thickness
- Why does cod need to be desalted?
- Optimal method: 24-48 hours (recommended)
- Rapid method: 4-6 hours (emergency express method)
- The milk method: a quick trick to soften
- How to tell if cod is properly desalted
- Common mistakes when desalting cod
- Desalting cod for different recipes
Key steps for desalting cod
Before getting into the detailed methods, these are the essential steps that apply to any desalting process:
- Initial washing : Pass the pieces of cod under the tap to remove the surface salt from the piece.
- Correct position : Place the pieces with the skin facing up so that the salt can flow down through the meat by gravity.
- Plenty of water : Use between 3 and 4 liters of very cold water for every kilo of cod. The fish should be completely submerged. The cold water helps maintain a firm texture.
- Refrigeration : Always keep the container in the refrigerator (4°C-5°C) to prevent the fish from spoiling or fermenting. Never leave at room temperature.
- Change the water every 8 hours : Essential for uniform desalination. Water saturated with salt stops extracting salt from the fish.
- Salt test before cooking : Cut a piece from the center, cook it for a few seconds, and taste it. This is the only reliable way to know if it's ready.
- Final drying : Once desalted, dry the cod well with kitchen paper before cooking so that it does not release water into the oil.
Desalting times according to thickness
| Cod format | Optimal time |
|---|---|
| Crumbs and crumbs (pieces <1 cm) | 12-24 hours |
| Thin piece (1-2 cm thick) | 24-36 hours |
| Medium loins (2-3 cm thick) | 36-48 hours |
| Thick loins or whole pieces | Up to 72 hours |
| Cod tripe | 36-48 hours |
| Cocochas (kokotxas) | 24-36 hours |
Why does cod need to be desalted?
Salt cod has undergone a curing process in salt that can last from three months to over a year. During this process, the salt penetrates the fish's fibers and draws out moisture. The result is cod with a salt concentration that can exceed 20% of its weight.
That high salt concentration makes cod inedible: it would overpower the flavor of any dish. Desalting partially reverses this process: the cod absorbs clean water and releases salt, returning to a salinity level suitable for cooking (generally between 1% and 2% residual salt).
The trick to any good desalting process is that the cod should regain its texture and moisture without becoming bland. Perfectly desalted cod has a subtle but perceptible saltiness that balances the flavors of the dish.
Optimal method: 24-48 hours (recommended)
Before getting into the express method, it's helpful to know the standard method because it's the reference point for understanding what we're sacrificing with the fast method.
What do you need
- Salt cod (any format: loins, flakes, whole piece)
- Large container (the cod must be completely submerged)
- Cold tap water
- Fridge
- A fork (for tasting)
Step by step
Step 1 : Briefly rinse the cod under cold water to remove excess surface salt. This isn't strictly necessary, but it reduces the overall cooking time.
Step 2 : Place the cod in the container with the skin side up. This detail is important: the skin acts as a barrier and slows down the loss of salt from that side, which helps to achieve a more balanced desalting process.
Step 3 : Cover with plenty of cold water. The cod should be completely submerged.
Step 4 : Put the container in the refrigerator. Never desalinate at room temperature : heat promotes bacterial growth and can deteriorate the texture of the cod.
Step 5 : Change the water every 8 hours. In a 24-hour desalination cycle, you will do 3 changes. In a 48-hour cycle, between 5 and 6 changes.
Step 6 : After 20-24 hours for medium-sized loins, taste a small piece from the thickest part. The cod should have a mild saltiness, noticeable but not overpowering.
Rapid method: 4-6 hours (emergency express method)
This method reduces desalination time to 4-6 hours by changing the water more frequently and, optionally, using warm water in the initial stages. It is suitable for small cuts (crumbs, thin loins) but does not yield the best results with thick loins.
When to use the quick method
- You forgot to soak the cod and you need it the same day
- Do you have cod crumbs or small pieces (they are desalted beforehand)
- You're preparing a recipe where the cod is shredded or mixed with other strong ingredients (brandade, fritters, croquettes), and a slight variation in the salt level is less critical.
When NOT to use the quick method
- You're preparing cod in pil-pil sauce: the texture of the loin is critical
- You have thick spines: the quick method doesn't reach the inside well.
- The dish depends on the exact salt level of the cod (recipes where cod is the only ingredient)
Step-by-step express method (4-6 hours)
Step 1 - Initial Rinse : Rinse the cod under cold water for 2-3 minutes, gently rubbing the surface. This removes the outer layer of salt and speeds up the process.
Step 2 - First soak in warm water (30 minutes): Cover the cod with warm water (not hot, between 30°C and 40°C). Warm water accelerates osmosis and extracts the salt more quickly than cold water. Leave for 30 minutes.
IMPORTANT : Warm water is only used in this first phase. If the cod spends too much time in hot water, the protein coagulates and the texture becomes rubbery.
Step 3 - Change to cold water : Switch to cold water and put it in the refrigerator. From this point on, the entire process is done in cold water.
Step 4 - Frequent Water Changes : Change the water every hour for the next 3-4 hours. The frequency of water changes is the factor that most accelerates desalination.
Step 5 - Intermediate test : After 3 hours, taste a small piece. If it's at an acceptable point for your recipe, you can proceed. If it's still too salty, continue for another hour.
Expected result after 4-6 hours : Cod with a higher salt content than the traditional method (slightly saltier than ideal) but perfectly cookable for most recipes. For pil-pil or more delicate recipes, you'll need more time.
The milk method: a quick trick to soften
There's a trick: soaking the cod in milk for two hours in the refrigerator helps to soften and desalinate highly salted cod. The milk proteins (caseins) partially bind to the salt compounds, easing the process and adding a slight sweetness.
Milk works well when : the cod is over-cured or has a very high salt content. It also works well as a final step before cooking to soften the final flavor.
Milk is not necessary when : the cod has a standard curing time. In that case, cold water with frequent changes is sufficient and more economical.
How to use milk (if you choose to): Substitute one or two of the water changes with cold whole milk. Do not use hot milk. Milk does not accelerate the desalting process; it simply softens the final flavor in heavily cured cod.
Prefer not to desalinate? At Bacalalo, we offer pre-desalted cod, ready to cook, selected with the same quality standards as our salt-cured cod since 1990. See our desalted cod in our shop.
How to tell if cod is properly desalted
The definitive test is always organoleptic: with the mouth.
The Bite Test
Cut a small piece from the thickest part of the loin (it takes the longest to desalinate). Chew slowly and pay attention to:
- Saltiness when you bite into it : there should be a mild saltiness, like that of a well-seasoned dish. If it seems too salty for your taste, continue cooking for another 2-4 hours.
- Texture : Properly desalted cod has a texture that begins to flake. If it remains very compact and rigid, it may still contain too much salt.
- Taste : It should smell and taste like the sea, clean, without rancid or strange aromas.
Signs that the cod is ready
- Mild but noticeable saltiness
- Pearly white color, homogeneous
- Flakes that begin to separate naturally
- Flexible texture, not rigid like the unsalted piece
Signs that the cod is too desalted (bland)
- Lack of its own flavor
- Excessively white, almost translucent
- Soft texture, no structure
If you've over-salted the cod, you can partially recover it by adding salt to the water for the next cooking or by using a more flavorful stock. There's no perfect way to reverse the situation, but it can be compensated for.
Common mistakes when desalting cod
Error 1: Desalting at room temperature
The most dangerous mistake. Cod soaked at room temperature (especially in summer) can spoil in just a few hours. Always keep it in the refrigerator, always.
Error 2: Not changing the water often enough
The water absorbs the salt until it is saturated: when the water can no longer absorb any more, the process stops. Frequent changes = efficient process. With the traditional method, every 8 hours is the minimum; with the express method, every hour.
Error 3: Using hot water throughout the entire process
Hot water accelerates salt extraction but damages the cod's protein, leaving it rubbery and without structure. It's only justified during the first half hour of the express method, never beyond that.
Error 4: Desalination with salt in the water
Some cooks add salt to the desalting water "to control the process." This is counterproductive: the cod will always release less salt than it already contains, and the salt water slows down the process.
Error 5: Desalting in a container that is too small
If the cod isn't completely submerged, the parts above water will desalinate unevenly. Always use a large container.
Error 6: Not drying the cod before cooking it
After desalting, the cod is soaked with water. If you put it directly into the hot oil without drying it, it will release water, the temperature will drop, and the cod will steam instead of browning. Always pat it dry with paper towels before cooking.
Desalting cod for different recipes
For pil-pil
You need the cod to be perfectly desalted and have plenty of available collagen. Use the traditional 24-36 hour soaking method. Pil-pil sauce made with insufficiently desalted cod will be too salty because the sauce reduces and concentrates the juices.
For brandade
You can allow for a slightly higher salt content because the oil and potato (if using) will balance it out. The 4-6 hour express method works well for brandade.
For fritters and croquettes
The cod is mixed with other ingredients, and the batter absorbs some of the salt. It can tolerate a more pronounced saltiness. The express method is perfectly valid.
For salads and esqueixada
Esqueixada (Catalan salad of raw, desalted cod) requires perfect desalting because the cod is not cooked. Use the traditional method of at least 24 hours and taste carefully.
For rice dishes and stews
The broth or stock in which the cod is cooked absorbs salt. Desalt it slightly less than usual and don't add salt to the stew until the very end, after tasting it.
Frequently asked questions about quickly desalting cod
What is the minimum time I need to desalinate cod?
For crumbs and small pieces, the minimum cooking time is 4 hours with frequent changes. For medium-sized loins, don't go below 6-8 hours with the express method, although the result won't be optimal. The standard cooking time is 24-48 hours depending on the thickness.
Can I desalinate cod in the microwave?
It's not recommended. Microwave heat partially cooks the proteins and irreversibly damages the texture. Heat and soaked cod don't mix.
Can you desalinate cod with tap water?
Yes, absolutely. Tap water is fine. Just make sure it's cold and that you change it frequently. Mineral water doesn't offer any advantage in this process.
Can I speed up the process with more water changes?
Yes. The frequency of water changes is the factor that most influences the desalination speed. By changing the water every 30-45 minutes in cold water, you can shorten the time, although the result will be uneven with thick pieces because the salt inside takes longer to diffuse.
Does frozen, already desalted cod require any additional preparation?
No. Frozen desalted cod only needs to be thawed in the refrigerator (6-12 hours) and is then ready to cook. It does not need to be soaked further.
Why does my desalted cod taste bland?
You've over-soaked the fish or soaked it for too long. It's difficult to completely reverse this: add salt to the recipe or use a stock with more flavor. Next time, reduce the soaking time or taste it before removing it from the water.
Can I reuse the desalinated water?
No. Desalting water is full of salt and has no practical culinary use. Throw it away.
Does desalted cod keep in the refrigerator?
Yes. Desalted cod will keep for 2-3 days in the refrigerator, well covered, or in a container of cold water. Change the water daily if you're not going to use it immediately.
When is the best time to buy pre-salted cod directly?
If you don't want to manage the process, if you need the cod immediately, or if you don't have room in the fridge for soaking, quality desalted cod is just as good as the kind you desalinate at home.
Can I desalinate cod in the dishwasher?
This technique (placing cod in a sealed bag in the dishwasher at a low temperature) is technically possible, but it's neither reliable nor recommended. The results are highly variable, and the risk of spoilage is high. Don't use it.
Is salt water good for desalting cod?
No. Salt water inhibits the diffusion of salt from the cod into the water. Only clean, unsalted water should be used. Adding salt to the soaking water would be counterproductive.
How to desalinate dried or stick cod (stockfish)?
Dried cod requires soaking for 3 to 5 days, with water changes twice a day. There is no reliable quick method for drying cod due to its extreme dehydration. It requires patience.
Conclusion: what to remember about desalting cod
Proper desalting is just as important as the quality of the cod itself. Here are the key points to remember:
- Always in the refrigerator : never at room temperature
- Skin facing up : for a more balanced desalting
- 3-4 liters of cold water per kilo of cod
- Changes every 8 hours in the traditional method, every hour in the express method.
- Always test before cooking : it's the only foolproof method.
- Dry before cooking : this prevents it from releasing water into the oil.
- The time depends on the thickness : from 12 hours for crumbs to 72 hours for very thick pieces.
If you need an immediate solution without compromising on quality, at Bacalalo we have cod already desalted and ready to cook, selected with the same demanding criteria that we have applied since 1990 at the Mercat del Ninot.
Buy desalted cod at Bacalalo — ready to cook, shipping throughout the Peninsula
