Even for the enthusiast, hot coffee that has cooled to room temperature is barely palatable. So, how do you keep it hot as long as possible? Other than buying an insulated thermos, there is a way you can fix your coffee at home to ensure a longer linger of heat to warm your fingers.
It sounds counter-intuitive, but immediately adding cold cream to your coffee actually helps keep it hotter for longer. The food scientists behind Modernist Cuisine have worked out why this is true with the laws of physics, but we’ll condense the scientific terminology for you. Cold cream works this small wonder on your daily cup of coffee for three reasons. Click through the slides to find out what they are.
01 Coffee with Cream Versus Black Coffee
It beats black coffee because…
Black coffee is a darker color than coffee with a splash of cream. You know that dark colors absorb heat faster than light colors, but they also emit heat faster than their lighter counterparts. This means your coworker’s coffee, which they ordered black, leaks its heat faster than your coffee with cream, which is a milky camel color.
02 Adding Cream to Coffee Earlier Versus Later
It beats adding cream later because…
Though the cream added immediately to hot coffee initially cools off your cup, it also slows the rate at which your coffee loses heat. Cooler objects lose heat more slowly than hot objects. So your coffee, which you added cream to right away, is holding pretty steady at its temperature while your coworker’s coffee, which they ordered black and brought back to the office, cooled drastically in transit. If they now add cold cream, the temperature will drop drastically, making it colder than yours.
03 Coffee with Cream Versus Coffee with Milk
It beats milk because…
Cream is thicker than milk; while that might not be great calorie-wise, it does wonders for keeping your mug warm. Though adding either to your coffee makes it thicker, cream gives you the most bang for your buck; this slows how quickly your coffee evaporates, a process that carries heat away with the liquid. (Popping a lid on your cup immediately will also help slow this process.)
So never settle for cold coffee again. Keep cream on-hand at home and ask for room at the coffee shop to slip in some of this heat-saver immediately.