Someone asked me that being such a coffee addict and having traveled the world, which coffee would you say is the best coffee in the world? I was stumped. How can you choose one. And everyone has different taste.On top of it all, each coffee flavor is unique in itself. My favorite flavor keeps changing with my mood.This is a bit like asking: "What is the best color"!
As a food product, the "quality" of coffee is a matter of taste.
The species of the shrub, the cultivar within the species, the altitude of the farm, the kind of soil in which the shrub is growing, the typical soil moisture, the level of coffee cherry maturity at harvest, the cherry processing methodology ( wet versus dry processing), the quality of "handling" before shipping, the care taken during shipping, how long the green beans sit in a ship's hold, how the beans are roasted, and then how the roasted beans are ground and brewed...ALL of these things have an impact on the flavor and "quality" of what is in your cup.
Do you like it? Then, to you it is high quality--perhaps even the best. You might like a very dark roasted coffee blended from Central American varieties that contains robusta beans along with arabica beans, prepared in a drip brewer. I, however, might prefer a single origin, dry-processed Ethiopian Yirghe Cheffe cup prepared as an espresso.
We're both right, because enjoyment of our coffee is a matter of taste--a matter of preference.
Don't let anyone kid you. No matter whether the coffee is picked by the biggest chef in the world, there is no such thing as the world's best coffee nor does the cost per pound (or gram!) determine the quality of the cup!