Could we find a thermal carafe that excelled with both hot and cold liquids?
Published Jan. 1, 2017.
If you like to entertain, insulated pitchers can come in handy. Also called thermal carafes, they keep coffee or tea hot for hours—perfect for brunch or a dessert table at a party. They also insulate cold liquids, so we sometimes use two: one for hot coffee and one for cold cream or milk. We’ve even used them to keep stock warm (and pour it as needed) when making risotto.
Most thermal carafes are double-walled and vacuum-sealed. (In other words, they have two stainless-steel walls, and the air between them has been removed. Without air, heat transfers much more slowly.) Given their similarity in design, does it matter which insulated carafe you buy? To find out, we rounded up eight models, priced from $21.99 to $72.07 and with capacities from 44 to 68 ounces, and spent two weeks putting them through their paces in the test kitchen.
We started with the most important test: heat retention. We filled each carafe with freshly brewed 161-degree coffee and recorded the coffee’s temperature every hour by pouring out a small amount and quickly recording its temperature. After 4 hours—a reasonable amount of time for a carafe to keep things drinkable—the coolest coffee was a lukewarm 138 degrees. Meanwhile, the coffee in the top performers was still quite hot at 152 degrees.
To see how the carafes fared with cold liquids, we chilled them with ice water for 5 minutes (a step most manufacturers recommend). We then emptied them, filled them with 37-degree milk, and left them at room temperature. By the 2-hour mark, all of the milk was at or above 40 degrees. After 4 hours, the samples ranged from 41 to 44 degrees. Bacteria grow more rapidly between 40 and 140 degrees, so the U.S. Department of Agriculture (USDA) recommends that food be in that range for no longer than 2 hours. We were discouraged that none of the carafes had kept milk below that threshold, but we suspected that they were still an improvement over a standard, noninsulated pitcher. Sure enough, when we performed the same test with a chilled stainless-steel pitcher, the milk climbed to 55 degrees after 1 hour and hit 67 degrees after 4 hours. Even the least effective carafe was a dramatic improvement.
With the temperature tests complete, a panel of testers evaluated how easy the carafes were to use. Four factors mattered most: the pour spout, the handle, the lid, and opening the carafe. Some carafes were hard to control, and liquids poured from them at unpredictable speeds and angles. Worse, liquids that were poured from some carafes continued flowing for an extra beat after we’d released the button—more than enough time to accidentally overfill a coffee mug. We much prefer...
The mission of America’s Test Kitchen Reviews is to find the best equipment and ingredients for the home cook through rigorous, hands-on testing. We stand behind our winners so much that we even put our seal of approval on them.
Kate is a deputy editor for ATK Reviews. She's a culinary school graduate and former line cook and cheesemonger.