Why does cold coffee taste sweeter with the same amount of sugar?

Question

I have observed that the same amount of sugar tastes differently in hot and in cold coffee. If I drink hot coffee, I feel I can add more and more sugar, without it tasting too sweet. However, cold coffee tastes overly sweet with only small amounts of sugar.

Why does this happen? Why does sugar taste differently sweet in cold and hot coffee?

Asked by tech_learner

Answer

Its possible that when you drink a hot liquid, you swish it around your mouth a lot less than when you drink a cold liquid, and thus fewer of the taste buds on your tongue are exposed to it. This wouldn't be surprising: it's hot after all.

Another possibility is that if you're starting with hot coffee, and adding sugar to it, that the sugar isn't fully dissolved when you drink it hot (it takes time, especially if you don't stir it much), but has dissolved by the time the coffee cools. With more dissolved sugar, it is sweeter.

Answered by derobert

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