This will alter how many coffees you can make at once. The capacity stated is how much milk the jug can hold when frothed, not how much ordinary milk to use.
You should only fill your milk jug up with milk by about a third, as it expands when frothed. As you will read below, the ideal ratio for coffee to milk is 1:3 to 1:5 dependent on taste, so work out how many millilitres your coffee machine espresso is and then buy a latte milk jug which will hold enough milk for however many cups of coffee you will be making.
The majority of milk frother jugs are stainless steel, which holds the warmed milk’s heat well and also won’t tarnish or become damaged. They’re also easy to clean fully.
Don’t use anything which isn’t metal or specifically for frothing – it could get too hot and become damaged, and may not froth well.
Many are a pretty standard size, but just double-check the dimensions of your chosen jug against the size and shape of your frother or the space around your frothing wand.
What Else To Look Out For
Check the pouring spout if you want to be able to pour the milk in order to create latte art. Many are perfectly angled but it may depend on how experienced you are creating it.
Also check things such as the handle and how comfortable you would find holding it, and how it can be washed. Most are hand wash only, but a few are dishwasher safe.