Mellow adds a new element to sous vide cooking -- cold. This $400 Wi-Fi-enabled countertop appliance creates a temperature-controlled water bath in which you cook meat, veggies and just about anything else you can dream up and put in a plastic bag (I'll explain more later). But unlike similar appliances, the Mellow will also chill your water bath until you're ready for it to heat your meal.
We've waited three years for Mellow's creators to get this product out there. For the most part, it was worth the wait. The Mellow achieves the biggest objective of sous vide cooking: heating food evenly for consistent (and delicious) results. And the Mellow's accompanying app is pretty easy to use -- select what you want to cook and when you want to eat it, then go about your day with the knowledge that a perfectly medium steak or flaky piece of salmon will greet you when you get home.
But it's not all bubbly water baths and tasty dinners with the Mellow. The size of the container limits just how much you can sous vide at once. The app doesn't provide much recipe help, and the manual mode leaves much to be desired. There are some discrepancies between the actual temperature of the water bath and notifications from the Mellow app. And the necessity of needing to chill your food prior to cooking, rather than simply letting a dish circulate all day, is debatable.
Consider the Mellow if you're a moderate sous vide enthusiast who doesn't want your food spending the whole day in a hot water bath. If you're still not sold on sous vide, go for a less expensive immersion circulator instead.
Sous vide (French for "under vacuum") is a method of cooking during which you place food in a vacuum-sealed bag and cook it in a temperature-controlled water bath. The circulating water brings your food to the temperature you want and keeps it there, which means you can cook a steak, for example, to your preferred doneness without any guesswork.
There are a few different devices that you can use to sous vide, such as immersion circulators or cooktops with connected temperature probes. The Mellow is an example of a complete sous vide system -- it's made up of a container for the water bath and a 1,000-watt heating element in its base to heat the water to the right temperature.
What makes the Mellow different than other countertop sous vide systems is the 50-watt cooling element and weight sensor that are built into the base. Here's how it works: You fill the Mellow's removable container with water and place it on its base. The Mellow detects the weight of the water, and automatically begins to cool the water down to 40 degrees Fahrenheit. That cooling allows you to keep your food in the Mellow at a safe temperature until you want it to start cooking your meal.
From there, you use the Mellow's app (available for iOS and Android) to select what you want to cook from preset cooking modes. There are plenty of foods to choose from, including basic cuts of beef and chicken to vegetables and octopus. Depending on what you cook, you give the app some info about what you're cooking, such as if your fish is frozen or fresh, or how thick your steak is. Select when you want your meal to be ready.
Then you slip your food into one of Mellow's branded 11 by 8.5-inchsous vide bags, slide the bag into the water to force the air out and pinch the bag shut. (You get 20 bags with the Mellow, and they're $10 a box when you buy them separately. But the company says you can use any Ziplock-type bag.) The Mellow will either begin to chill the water until it's time for it to begin cooking, or it will heat the water if you want your food ASAP.
The idea behind the refrigeration is that you can put a piece of salmon, for example, in the Mellow in the morning, use the Mellow's app to schedule when you want that salmon to be ready, and go about your day without having to worry about your fish floating around in room-temperature water until you want to hit the "on button." (And speaking of buttons, there are none on the Mellow. You control everything through the app.)
This is all fine and dandy, but some sous vide fans might not see the necessity to cool your water before it's time to cook. The concept of sous vide is to get water at a stable temperature; you can begin to sous vide your salmon in the morning and any decent sous vide product will hold the set temperature for as long as you need it to without overcooking the salmon.
But we've seen in our test labs how the structure of a tough piece of meat like a flank steak can change when you sous vide it over a long period of time; it goes from tough and chewy to delicate and tender, which might not be the best for every food item. Mellow gets rid of that possibility. It will only cook your food for exactly as long as you want it to.
The Mellow is at its best when you follow the cooking recommendations of its accompanying app. Steak that I prepared according to the app's preset temperatures surpassed what I cooked on manual mode using the standard cook times and temperature settings I use for sous vide tests. Thick cuts of New York strip steak were melt-in-your-mouth tender and juicy, and were cooked consistently throughout the meat. I set the Mellow to cook the steak to medium, though it's version of this doneness was a smidge on the medium rare side.
The Mellow lived up to its assertion to maintain temperature accuracy of plus or minus 1 degree Fahrenheit. However, there were some discrepancies between the actual temperature of the water in the Mellow versus what the Mellow app told me through notifications. For example, I cooked a steak at 140 degrees Fahrenheit. I wanted it to cook right away, so the Mellow began to heat the water immediately. I eventually received a push notification that the water had reached my desired temperature, but our test lab's temperature probe and the Mellow app showed that the actual temperature was still half a degree below 140. A Mellow spokesperson said the company is "working to improve the accuracy at the steady state temperature," and the next software update should reflect improvements in that area. It's good that the company recognizes this, but it's a little disappointing to have to wait for more accuracy.
The Mellow's size also made me cue the sad trombone. The appliance is 15.8 by 6.7 by 12.5 inches, and its water container can hold 4.5 liters. This is great if you're short on space and don't need to cook a lot of food simultaneously. But the narrow structure will limit the cook who wants to sous vide for a crowd. For example, a large cut of flank steak wouldn't fit into one of the Mellow's bags, let alone the container.
I also had some beef with the Mellow app. It's not immediately clear what your current water temperature is unless you decide to start cooking. And there is very little by way of actual recipes within the app -- you need to already know how to season and prep your food before you put it in a bag. That's a shame when you consider other sous vide companies, such as Anova, fill their apps with cooking guides and recipe suggestions.
The Mellow has its faults. But at the end of the day, it's a device that's reliable in creating meals that are cooked just as you like them. This is an appliance for someone who knows a thing or two about sous vide -- but stand down if you're still not sure about water-bath cooking.