Slurping helps cooling drinks primarily by increasing the rate of convection. Firstly you increase the thermal gradient by circulating the hot air surrounding the liquid replacing it with cooler air, secondly you also increase the surface area of the liquid, allowing more heat to transfer.

Why do people slurp?

As I said earlier, slurping forces the tea to vaporize, in so doing it mixes more readily with Oxygen before hitting the inside of your mouth. This helps you to amplify the aroma, making the tea taste and feel much better than it usually would.

Why do people slurp hot coffee?

You want to slurp coffee quick enough so that it gets aerated and spreads all over your tongue and palate. That way your tongue can fully register the taste sensations. ... So when you slurp, both your taste buds and your nose get involved and you really truly taste the coffee. So you need to slurp.