When you make coffee, the water cools, eg the rat-tails from an espresso being made (with water at 85-95 C) have a large surface area which leads to cooling as

When you make coffee, the water cools, eg the rat-tails from an espresso being made (with water at 85-95 C) have a large surface area which leads to cooling as the coffee enters a cup. A ceramic cup/mug will leech out heat, despite being kept warm (about 40 C?). Drip coffee often sits on a heater, but the temperature is relatively low. McDonalds reportedly used higher temperatures to extract more coffee, and kept their coffee very hot, enough to cause third degree burns in the Hot Coffee case IIRC. They had many complaints and refused to lower the temperature. So, McDonalds don't need to cool it so much as not heat it so much. Drinking temperature is below 70 C, McDo were reportedly giving it to people at 90+ C, reports say 20 C above industry norms; hotter than being temperatures. Blaming customers who are very familiar with buying coffee for not knowing you purposeful heat it to a much higher temperature would be crass in the extreme. Like selling Chicken Korma (a very mild curry) and putting ghost peppers (very hot spicy peppers) in it, and refusing to add a warning or anything when lots of people complained.