Why You Should Always Use Cold Milk When Frothing Milk For Lattes

Frothing milk for your morning latte may seem like something better left to the pros, but there are a few tips and tricks to make this process simple enough to do at home. Though you can use a milk steamer or French press, a hand-held frother is an easier (and more cost-effective) way to get the job done. These little devices run as low as $6.95 on Amazon, and all you have to do is stick them in a cup of milk and press the button until you see bubbles.

The type of milk you use also matters, as even the best tools can't turn some kinds into foam. And though you're aiming for a hot latte, you're going to want to froth that milk when it's extra cold; so if you're using a steamer, start with cold milk in a chilled steaming jug — you can even pop it in the freezer for a minute or two before frothing. This is because milk that is hot, or even lukewarm, is very difficult to froth into an airy foam — but why? 

The reason warm milk is hard to froth is due to the proteins in milk, which unwind when they become too hot and aren't able to properly create the structure necessary for bubbles to form. But maybe you don't want to pour cold milk (frothy though it may be) on your warm drink — and if that's the case, you can heat it up afterward, which will actually make the foam set.

There are a few other factors to keep in mind too. Aside from potential spoilage issues, old milk can be very difficult to froth. Higher-fat milks, like whole and 2%, will create a thicker foam with smaller bubbles, while lower-fat ones will produce froth that is fluffier, less dense, and a little blander. If you choose whole-fat milk, take your time and don't rush the process too much – more fat means the bubbles take a little longer to surface, but the end results will be worth it. If you're a fan of non-dairy milks, oat and coconut versions also work beautifully here. But whichever kind you choose, make sure it's fresh, and straight out of the fridge.