Posted: Aug 15, 2006 9:21 pm
Actually, strength is determined by two factors: amount and fine-ness of grind, but more strength is mainly determined from the later. Both French and Italian roasts have enough oil released at their respective roasting stages to make espresso.
Think of a coffee ground as a little serving plate of the oils, flavors and tanins (you can actually apply this analogy to most cooking) that make up coffee. When the hot water passes through coarse grinds, it only "washes off" whatever is on the surface of the server plate; therefore, the finer the grind, more surface area is exposed, and will make a "stronger" concentration of oils, flavors and tanins to water. And, obviously, if you add more coffee to your filter you will do the same.
Overall, I prefer a dark french roast to italian, because it's right there at the edge of burning, with a little less bitterness. As for espresso, I do prefer the Italian roast, because water passes through the grounds for a short period of time, leaving most of the bitterness still "stuck" to the "serving plate".
But, overall, coffee is like music and is completely subjective to each person's experience. People like what they like, and there ain't nothing wrong with that.