If you think froth is “so 2020,” be assured it’s still cool.
Cold foam is here (and here, and here) to prove it’s a lasting trend. Cold foam is a fluffy, frothy topping of aerated (but not heat-steamed) milk that floats atop cool beverages like one of Bob Ross’ happy little clouds. It is usually prepared with skim milk, and it’s often slightly sweetened.
But it’s so smooth and nice…are you sure cold foam isn’t just whipped cream?
A popular example, Starbucks Cold Foam, is made with sweetened, aerated skim milk, and is what most consider the platonic ideal of cold foam. Some coffee purveyors may employ whipping cream to achieve a similar effect. We won’t call this practice cheating outright, but it is a kind of cheating. Since cold foam is usually sweetened, bear in mind you’re not exactly getting a diet drink even if the place you get your cold foam from is one that uses skim milk.
How does cold foam differ from hot foam?
A wise guy, eh? Well, it’s cold, for one. But more earnestly, “cold foam” is prepared cold as well as served cold, which makes it more suitable as a topping for cold beverages such as cold brew, iced lattes, and even non-coffee drinks. It will usually be a poufier foam than the tight, sleek microfoam that is customary for hot drinks in specialty-style cafes, where steamed milk is served integrated into the coffee below. The larger-sized bubbles in cold foam are in part due to the temperature at which the milk is foamed, explains Professor Thomas Huppertz, a milk researcher at Wageningen University & Research in the Netherlands.
“The bubble size immediately after foaming is typically mainly related to foaming technique used,” says Professor Huppertz. “However, as soon as the foam is made, some destabilization also occurs, which will result in larger bubbles. That destabilization is typically higher in milk foamed at lower temperature.”
Huppertz also notes in his great 2014 Re:co Symposium talk “The Science of Milk Foam,” that skim milk foam can be quite persistent—lasting for a long time while not dissolving downward into the drink. For a drink like a cold foam cold brew, this allows the multi-textural experience of sipping cold coffee through a layer of cool foam to stay the same throughout the enjoyment of the beverage.
What about fat content? Why is skim milk the best milk for cold foam?
“Skim milk is great for making foams because it’s enriched in the whey proteins that stabilize foams, and largely free of the milk fats that destabilize them,” explains food chemistry expert author Harold McGee. To put it more plainly, it’s a slam dunk to aerate skim milk—foaming milks with higher fat content will need a bit more patience and skill.
Can you make latte art with cold foam?
It’s possible! But it’s harder due to the typically different structure of the foam. You may also find cold foam more often dolloped atop cold brew, rather than free-poured over a viscous espresso. That hasn’t stopped people from trying to make cold foam rosettas, however.
Can I make cold foam at home?
Yes, and it will be an easier task than making barista-quality steamed microfoam for sure. Go ahead and grab your skim milk, that frother you got as an office gift 10 years ago, and a little bit of simple syrup and vanilla. If you don’t have a frother, you can aerate that milk-and-vanilla-sweetness with a blender or hand blender, or if it’s arm day, crack out that whisk or shake the liquid up in a mason jar or even agitate it in a French press by repeatedly plunging up and down! If that’s too much of a workout, a substance that appears to be whipped cream but is called cold foam is also available from whipped cream manufacturers who just could not sit on the sidelines for this one.
You said cold foam comes in different styles and flavors. What are some?
Some varieties of cold foam we know about are: Vanilla Sweet Cream, Salted Caramel, Matcha, White Lightning, Pumpkin Spice, Pistachio Cream, and a flavor called “Avalanche” flavor at Biggby coffee which claims to contain white chocolate, mint, goodness, and magic. Whatever added ingredients (or magic) you prefer, cold foam could just provide that extra dollop of intrigue next time you’re thirsty for something on the cold side.
Liz Clayton is the associate editor at Sprudge Media Network. Read more Liz Clayton on Sprudge.