How to heat milk ? | hot chocolate machine

Hi there,

I'm starting to think about if it would be possible to build a hot chocolate machine like an espresso or coffee machine, but with milk (not water).
Today I googled about machines of the same kind and I just found machines which use water.

My problem is I don't know how to heat the milk.
While googleing I found out that some espresso machines are using a thermoblock to heat water and milk for cappucino.
Do you have an idea how I can heat milk ?

  • Can I heat milk with a thermoblock ?

Milk is difficult to heat because of its viscosity.
The milk near the heater will get hotter than milk further away.
With no stirring, the near milk will over heat and burn onto the heater.
You can use a microwave, but some people do not like food irradiated.

No matter what method is used, cleaning can be an issue.

The other problem with milk is that its volume increases very suddenly when it boils so that it overflows and makes a mess.

What about using steam to heat it as is done in coffee shops? That way the milk can be heated in the cup from which it will be drunk which makes the cleaning easier.


Hot chocolate machines do exist. I think most of them are heating water and then adding the milk+chocolate powder after it's heated.

Cleaning is going to be the issue. The parts that touch the milk must be totally removable and cleanable. Perfectly smooth stainless steel is required for everything. If you can do that, then placing one of those parts inside a heating element is not going to be difficult. You won't get perfect transfer of heat from the heater to the stainless because there will always be some air gap. But if it's plugged into the wall you don't care too much about a small loss in efficiency. (Battery power would be different.) You can call this device a "thermoblock" if you want. That's a made-up word anyway.

Yep. Vending machines use dry milk.

Before designing a machine to heat milk, design one so you can easily clean it.