You have the questions, we have the answers

Scientifically speaking, milk foams because of the proteins in the milk. As milk is heated, these proteins denature and unwind. This causes them to bond together and create a stable network of air bubbles. This network traps air, creating a thick foam on top of the liquid milk, and a beautiful silky texture in your flat white or latte. The protein content of different types of milks varies greatly. Whole milk has a higher protein content than non-fat or low-fat milk, with around 3.3g of protein in 8 ounces of whole milk. However, non-fat or low-fat milks can contain up to 2.5g of protein per 8 ounces, while almond, coconut and soy milks contain much lower amounts of protein. This is why whole milk is the most popular choice for foaming, as it produces the best result in terms of flavour and texture. Happy frothing! :)

If your milk is not foaming, it could be because the milk itself has gone bad, the temperature of the milk isn't warm enough or there is too much fat content in the milk. It's also possible that you are not whisking or steaming correctly - make sure to whisk vigorously and steadily until you achieve a thick foam with a gloss-like sheen on top. You may need to adjust the temperature or experiment with different types of milks to find one that works best for you.

To know if you've foamed the milk correctly, look for a thick, glossy foam that will slowly dissolve when stirred with a spoon. The foam should be light and airy, not gritty or bubbly. A beautiful sheen on the surface of your foam, almost like gloss paint, indicates you are getting good results. If it's too thin and watery it means, there is not enough air in the mix – try again!

The best milk to use for foaming is whole milk. Whole milk produces the most stable foam, giving the best flavour and texture. Non-fat or low-fat milks may produce a thinner foam due to their lower fat content, but can still be used for frothing and steaming if desired. Almond, coconut and soy milks will not produce froth as well as regular cow's milk but can also be used in specialty drinks like lattes or cappuccinos.