Bitter Coffee? Adjust your grind!
July 25, 2008
I’ve written previously about the importance of using the proper amount of coffee (hint – most instructions you see tell you to use too little), the proper temperature and the proper grind to avoid a bitter (or sour or burnt-tasting) cup of coffee. But where do you go when you’re doing it right and it still isn’t good?
The other day I was in Starbucks, and decided to take home a pound of their Pike Place Roast — one of the few brewed coffees from Starbucks that I’ve ever liked. I’d had it brewed in the store many times and enjoyed it, but this time I was out of beans at home and wasn’t in the mood to roast, so I figured I’d try some at home.
To my surprise, my first pot with Pike Place had a very unpleasant bitter, almost metallic note to it. I’d never experienced this in the store, so I knew this wasn’t right.
After thinking about it a bit, on the next pot I adjusted my grinder (a Kitchenaid Pro Line Burr Coffee Grinder – a stunningly good grinder for the money, for everything but espresso) one notch coarser.
Excellent — maybe even slightly better than Starbuck’s press-pot version.
Here’s the reason I coarsened the grind — bitter notes in coffee are almost always the result of “over-extraction” — trying to take too much flavor out of the bean. The “good flavor” is only in about the first 3/4 of the flavor that CAN be extracted — the last quarter contains all of the harsh bitter notes. Two things can cause over-extraction — not using enough ground coffee (about a cup for 8 cups of coffee), or grinding too finely. The more finely you grind, the more surface area of the bean you expose for extraction. By going slightly coarser, I caused it to extract less, and left the bitter note in the used-up grounds, not in the cup.
(FWIW, this is also why you’ll always get a better cup of coffee from a (properly adjusted) burr grinder than from one of the “blade” grinders — the burr grinder will produce very consistently sized grounds, while a blade just “chops” and always leaves some very large pieces and some very small pieces — as a result, you don’t get as much of the “good flavor” out of the big pieces, and you get bitterness from the tiny pieces)
Have you found anything new lately to improve your coffee experience?