Can anyone explain why hot water tastes different to cold water? Is taste not separable from temperature or is there another mechanism at work?
1) We actually can sense "coldness" or "hotness" as separate tastes. Think about mint candies or pepper for example.
2) Our receptors have different sensitivity based on the temperature. For example cold sweet drink feels much less sweet. That's why warm cola is disgustingly sweet for example.
And water does contain a lot of dissolved salts which have a taste.
3) More than half of the taste we feel is actually coming from the smell, and warm water contains more vapour, and therefore, more smell.
So our brain takes all these inputs from different sources and synthesises the feeling of taste in our brain.
Source of this knowledge is from: https://www.cookingforgeeks.com