The optimal brewing temperature for coffee is 86-92°C during the brewing process. At the outlet of the coffee machine, the temperature should be approximately 85°C. The optimal cup temperature should be around 67°C.
The optimal brewing temperature for espresso is 92-96°C during the brewing process. At the outlet of the coffee machine, the temperature should be approximately 88°C. The optimal cup temperature should be around 70°C.
So that coffee doesn't cool too quickly in the cup, you should preheat your coffee cup. You can do this by pouring hot water, preferably from the coffee machine itself, into the cup and then pouring it out. This will give you significantly better coffee aroma.
If coffee or espresso is brewed too hot, it can taste very bitter. If coffee or espresso is brewed too cold, it often tastes sour. The main factor in coffee brewed too cold is a scaled coffee machine. If you feel that the coffee tastes too cold or sour, you should definitely descale your coffee machine.
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