Sous vide is a method of cooking that is wonderfully diverse and can work well for just about any type of food. Fish and shellfish are no exception, and whether you like your fish perfectly flakey or more like sushi fish, this is all possible with the accuracy of sous vide.
Fish are very sensitive to temperature changes, and even small temperature variations can result in a very different texture. There are also lots of different types of fish, and one temperature rule will not apply to them all.
We thought we’d give you a little bit of a guide to cooking fish sous vide, so that you can whip up a seafood feast, no matter what your preferences are.
Cooking sous vide fish safely
As would also be the case with traditional cooking methods, you need to be aware of food safety when preparing anything sous vide.
We recommend the freezing of ﬁsh at -35ºC for not less than 15 hours or -20ºC for not less than 24 hours (EC Regulation 853/2004 as amended). Any food in which the microbiological hazard is believed to be within the product, i.e. not on the surface, should be subjected to a process that destroys such internalised organisms.
It is important to ensure you are heating any fish you cook to above 54.4°C (130°F) for an extended period of time, unless it is fish that you would be safe to eat raw. You also need to make sure you are not serving it to anybody who is immunodeficient if it is heated below this temperature.
Preparing fish for sous vide cooking
It is a good idea to portion your fish out before you cook it sous vide. Once it has been cooked, it tends to be very delicate, so cutting into it will make it fall apart.
Separating it into the desired portions before you cook it will make handling it much easier.
If you are going to be cooking more than one portion in the same bag, it’s a good idea to add a little bit of fat to the bag to prevent the portions from sticking together. A little olive oil or butter should suffice.
Be sure to avoid setting your vacuum sealer to too high a pressure as this can change the texture by crushing the fish.
Brining sous vide fish
One of the most popular ways to prepare fish before cooking it sous vide is brining. Brining helps the fish to firm up, which is especially helpful when you are cooking it at low temperatures. It also helps to pull out the albumin, which makes for a cleaner looking dish.
You can either make a wet brine or a dry brine. For a wet brine, you will usually need to combine salt with water at a 5%-10% salt to water ratio, and heating it until all of the salt has dissolved. Sometimes brines will also have sugar or spices added too.
You then cool the brine by chilling it, before adding the fish for 5 to 15 minutes.
A dry brine is very easy to use, and faster to apply than a wet brine. All you need to do is heavily salt the fish, and then refrigerate it for at least 30 minutes. Be sure to rinse exercise salt from the fish prior to cooking to prevent a very salty finish
Depending upon the specific dish, for some fish, you may wish to give it a quick sear after cooking it sous vide. For poached or low-temperature cooks you may wish to skip the searing step.
If you do opt to sear your fish it is important to ensure the pan is very hot and the fish very dry. Avoid searing so for more than 20 to 30 seconds for each side. Fish can overcook very quickly, so be sure to keep an eye on it.
We hope this has given you a little bit of insight into how best to cook fish sous vide. Be sure to check out our fish and seafood recipes if you would like more info on times and temperatures, as we have plenty of step by step recipes for cooking everything from crab to king prawns.
We also have a handy calculator for figuring out the correct cooking time and temperature, which includes our advice for seafood and shellfish.