This is a brief article on the importance of preheating your mug. This incredibly simple step is almost never done. Even good Coffee shops miss this one frequently. Pay attention next time you go to your local coffee shop. See if they preheat their porcelain cups before they pour drinks in them or if they preheat their cups before they pull shot of espresso into them. Chances are they do not.
There are two reasons this step should not be overlooked. Coffee served in a preheated mug stays warmer longer. This is a particularly helpful tip for making your travel mug last longer. The coffee I brewed at my coffee shop stayed hot longer if I brewed them in a pre-warmed decanter.
More important though is the effect pre-warmed containers have on espresso. Espresso is more sensitive then brewed coffee. It is served in a smaller volume and more concentrated. Whenever there is a variance in temperature, it will cause the espresso to become bitter. This becomes particularly evident if you have ever tried to make iced coffee, but that is another article.
All it takes is a little rinse of your mug and coffee pot with some hot water before you pour or brew and your coffee with markedly less bitter and stay hot longer.