Coffee with hot milk but without hot water compared to coffee with 75% hot milk and 25% hot water. Seems the latter retains more heat. Note: Final beverage quantity of both cases are same and also assume milk and water having same temperature while making beverage.
In: Physics
If the milk and the water being added are at the same temperature and added at the same time, there are only three factors at play: the specific heat capacity of the liquid being added, the boiling point of that liquid (or I suppose it’s corresponding volatility at the relevant temperature) and its thermal conductivity. The last two are pretty much the same between water and milk (<1%), but the former is around 10% lower for milk, which could explain the difference. That’s still pretty small though, so I feel there could be other factors at play (i.e. the first two criteria I stipulated are not met).
Edit: I guess four factors, as the latent heat of vaporisation is relevant to heat loss to evaporation as well as the boiling point. However it seems that this is more or less comparable to the specific heat between the two liquids (someone correct me if I’m wrong).
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