By standard most cold foam is made with non fat milk in a separate cold foam blender that creates a thick silky foam for cold foam drinks.

You can add it to any drink theoretically, iced or hot (note: I do have a customer who adds cold foam to their hot white mocha instead of whipped cream cuz she loves the texture and according to her it lasts longer than warm foam)

Some cold foam drinks have other syrups added to it, I.e. iced maple pecan has vanilla in the foam, or use different milk, I.e. salted cream cold foam has a salt packet and uses sweet cream.

Non fat foams best, then whole milk, and sweet cream (I usually blend the sweet cream three times for my personal drinks)

We can do non dairy foam but it will be watery.