Why Aren’t Café Drinks Piping Hot?

Latte Art 3 (c) Kim San So CC0 1.0

Last year, I started volunteering at a coffee shop. I learned to make a variety of milk-based drinks including Lattes, Mochas, and London Fogs. While attending my training session, I was instructed to steam the milk to 145°C. For extra hot drinks, the milk can only be steamed to a maximum temperature of 170°C. When I tasted the drinks I made, they were sweet and creamy, but they were not hot enough.

During one of my shifts, I was curious to see what would happen if I steamed the milk past the set temperature. As the milk neared 175°C, I turned the steamer off; the milk frothed up drastically and the temperature rose to 180°C. I proceeded to make my drink, but it tasted somewhat weird. This made me wonder, did I burn my milk?

What happens to milk when heated?

Milk is an emulsion of fats, proteins, water, and lactose. When heated, some of the water evaporates, while other components become more concentrated. If the milk hits 180°C, the milk proteins coagulate and thus create curdled milk.

Standard milk-based drinks should be heated to only 140 to 160°C. Within this range, the milk is sweet since the lactose (the milk’s sugar) breaks into smaller, simpler sugars. Unless purposely scalding milk for baking purposes, the milk should not be heated past 180 °C even for extra hot drinks, as the milk proteins and enzymes will be completely denatured.

It is understandable some may wish to order a piping hot drink because they stay warmer for longer. However, if all that you are looking for in a cup of coffee is its hot temperature, I suggest you opt for a cup of Americano or Espresso. Although these drinks are not milk-based, they are hotter and you will still be able to enjoy a quality caffeinated drink!


Speak Your Mind