Why does steam warm up a cappuccino coffee

Forming a bond releases energy introducing calorimetry 

To make a cappuccino coffee, pass high-pressure steam through a cup of cold milk to make it hot, then pour coffee through the milk froth. The necessary steam comes from a kettle or boiler. 

A kettle or boiler heats water to its boiling point to effect the process  

Much of the steam condenses as it passes through the cool milk. This condensation occurs in tandem with forming the hydrogen bonds responsible for the water being a liquid. These bonds form concurrently with the liberation of energy. This energy transfers to the milk, explaining why its temperature increases. 

Calorimetry is the measurement of energy changes accompanying chemical or physical changes. We usually want to know how much energy is liberated or consumed per unit mass or mole of 

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