Sous vide is a method of cooking that involves vacuum sealing your food in plastic and cooking it in a water oven — that is, a tightly temperature-controlled bath of water, usually at a relatively low temperature compared to more traditional cooking methods, over a longer period of time.
Sous vide, French for "under vacuum", is said to have several advantages: the lower temperature allows a more even heat penetration throughout the food, resulting in food that is cooked more evenly, while vacuum sealing the food allows it to cook in its own juices, maintaining flavour and removing the need for pan-greasing agents, such as butter, fat or oil. Many high-end restaurants use sous vide to pre-cook steaks, for example, because it ensures the same result every time, removing the guesswork.
As sous vide moves out of the restaurant and into the home, we got to test drive one of the few sous-vide machines on the Australian market: the Breville Sous Vide Supreme.
At 29x29x36 centimetres, it's a hefty beast, taking up quite a bit of kitchen bench real estate. If you think it's something you'll use fairly often, that real estate might be worth it, but it comes with a few caveats. The first is that food does take longer to cook. As you can see in our video, medium steaks and salmon take at least 40 minutes, and that's not taking into account browning. (When you cook food sous vide, you lose the Maillard reaction, the chemical reaction that turns the food brown and crispy, because the outside temperature isn't high enough for searing.)
On the plus side, you can just set and forget, walking away for that time and letting the sous-vide machine work its magic; or you can use that time to prep the rest of the meal. One thing we particularly liked was the idea of vacuum sealing up a bunch of food, sticking it in the freezer and pulling it out and popping it in to cook as needed, no thawing required, and because the food doesn't come into contact with the water, you won't need to change it with every use.
Of course, when you are using it, you do need to let the water warm up (unless you're comfortable leaving the machine plugged in while you're out all day, as you do with your fridge), and putting frozen food in rather than refrigerated or room temperature means you add yet more minutes to the cooking time. If you're making yourself a meal after a day at work, anything that adds to the cooking time is generally considered a negative. One way around this would be to put your food in to cook before you leave in the morning — with sous vide, there's no such thing as overcooking, or so we've been told.