IN A YEAR without commutes and trusty travel thermoses, not to mention office Keurig stations, we’ve struggled to keep hot brew at hand as we work from home. (And yes, your microwave is doomed to corrupt the flavor of even premium beans.) So we set off in search of insulating mugs to solve the problem more elegantly than a bulky plastic thermos, which seems uncivilized at home, and more effectively than thin, ceramic vessels that render a cup of java tepid before you’ve barely sipped half.
Armed with a kettle and a kitchen thermometer, we tested options ranging from high-quality classics like Le Creuset’s stoneware mug to app-enabled versions like the Ember Mug, which uses microprocessing technology to keep coffee or tea at a consistent temperature. We measured how long each option sustained coffee’s toastiness before the brew cooled to a temperature of 110 degrees, our definition of “lukewarm.”
Maintaining coffee’s heat guarantees more than a sense of comfort, according to Rod Johnson, co-founder of the Iowa-based coffee and tea company Blk & Bold. No matter what quality of beans you’re using, tepidness can ruin a cup, he said: “With hot coffee, you really get an opportunity to experience how it was meant to be enjoyed. Those flavor melds come through, and they’re so much more prominent than they would be in a flat, warm cup of coffee.” And don’t think that nuking your cupful in the microwave is a quick fix: “It impacts the drink’s chemical makeup and simply ruins how it tastes,” Mr. Johnson warned.
Here, our mug picks for caffeine fiends who pound their cup back relatively quickly, leisurely sippers who spend hours with a single cup and everyone in between.
1. For Speedy Sippers
Le Creuset Mug
Coffee gets lukewarm in: 30 min.
