Sous Vide Machines
How we tested
For sous vide cooking, vacuum-sealed food (the name literally means “under vacuum”) is immersed in a water bath that is heated to the food’s final serving temperature (e.g., 125 degrees for salmon). And because vacuum-sealing prevents moisture loss, the food can be held in the bath for hours without risk of parching or overcooking. Sous vide is great for not only foods that can easily dry out or overcook but also those that need tenderizing, like tough cuts of meat. (Food safety isn’t usually an issue since cooking times required are typically long enough to pasteurize food.) High-end restaurants have used this method for decades, but home versions of the appliance have been few and expensive, at least until recently. A few years ago, we recommended the first home water oven, the Sous Vide Supreme ($429), but it’s large and pricey. Now there are more options, including two styles: self-contained insulated boxes called water ovens (like the Sous Vide Supreme) and stick-like circulators, which attach to the inside of any cooking pot and continuously heat and circulate water (no stove required). We tested five new smaller, cheaper machines—two water ovens (one being the Demi version of the Supreme) and three stick-style circulators priced from $199 to $329—preparing eggs, salmon, and pork belly. (Note: A vacuum sealer wasn’t included with any of the models; one must be purchased separately. Alternatively, food can be put in a zipper-lock bag.)
Circulators versus Water Ovens
Right out of the gate we had issues with both water ovens. One model heated the water quickly, but only because of its wee 3-quart capacity, which allowed room for just two salmon fillets. Another machine had a much more reasonable 2.3-gallon capacity, but took almost an hour to bring the water up to temperature—annoying since you have to wait to add food until the water bath is fully preheated. Meanwhile, the stick-style circulators brought an equal amount of water to temperature in just 15 minutes—plus, they kept the temperature more stable.
Why such a time difference? Water ovens rely on slow-moving, passive convection currents to heat the water, while circulators actively pull water to the heating element and disperse it, continually doing this to bring the water up to, and maintain, temperature. To illustrate the difference, we attached each of the stick-style circulators to identical vessels each filled with 6 quarts of water, started their motors, and placed one drop each of blue and yellow food dye in opposite corners of each container. Within 15 seconds, the water in all the containers was evenly green. Meanwhile, one of the water ovens took 10 times as long to perform the same task. On the downside, stick-style models were noisier and food was jostled a little, though not enough to be bothersome (except when eggs were knocked about with one model) or damage the food.
The stick-style circulators also won us over for their versatility. Water ovens can accommodate only a fixed amount of water and food, while circulators can be attached to any household container, small or large (coolers are a common choice). The manufacturers of the stick-style circulators all recommend a maximum capacity of around 5 gallons, more than twice the capacity of the largest water oven in our lineup. And at the end of the day, they’re still small enough to store in a drawer or cabinet.
Making Sense of Maximum and Minimum Water Levels
That versatility does come with a potential problem: water evaporation. Both stick circulators and water ovens specify minimum and maximum water depths. These markers serve simply as guidelines for the water ovens, denoting where the bath should be filled to in order to properly cover food. They also indicate the maximum water allowed while still preventing overflow when bags are added. But those markers are crucial for circulators, which have sensitive electronic parts that could be damaged if the water level is too high. And if the water drops below the minimum level—a possibility if enough water evaporates from the open container—the circulators can no longer pull it into their heating ports, and they will stop operating. We found that it was a real issue only when we were cooking at higher temperatures or for 12 hours or longer (when we cooked pork belly at 144 degrees for 48 hours, we had to occasionally add water even though we did our best to cover the pots with foil to slow evaporation). Such long cooking times aren’t all that common, but stick models that allowed for a bigger range between maximum and minimum water levels at least gave us more time between refills when the situation did come up.
Despite their few drawbacks, stick-style machines took home gold, silver, and bronze. They heat the baths in minutes, are adaptable for different cooking quantities, and take up a fraction of the counter space of the bulky water ovens. They’re also significantly less expensive.
The Best Sous Vide Machine
Our winner, the Anova One, was the quickest and quietest of the bunch. Its large touch-screen display was intuitive and easy to use. It’s also the only machine with an outport that rotates to let you direct water circulation away from the food, reducing jostling. Whether you are a pro or novice, it's a worthwhile investment for home cooks interested in sous vide cooking. (Note: At press time, the company announced a newer model, which we will test when it launches.)