On dialing-in dark roast coffee (for light-roast fans)

Background: There’s a guy I’ve encountered on Twitter who has a coffee review site. He tweeted this morning something about how he reviewed a holiday blend from Batdorf & Bronson, and he didn’t like it so much he couldn’t finish it. Oh wait. What he tweeted was that Batdorf tweeted something about how he (@cornerofthecafe) didn’t like it but Alton Brown did. Anyway, it caught my eye and made me curious about how he reviews coffees, so I asked him about his process. The latter part of what follows can be read on its own, or you can read the tweets here.


Based on your replies to me, you use a minimum of 3 devices (you listed 4 here, but mention “3–4 devices” so I’ll say 3 here). You wrote that you grind “on Preciso at different intervals in a range from 10–18.” I think it’s fair to say you’d be employing a minimum of 3 different grinds then. You also mention brewing at different temperatures, which I’m going to assume is also 3 different temperatures. I asked about brew time adjustments, and you responded positively, but I’ll assume 2 different brew times. By this math, you brewed the coffee a total of 54 times. Based on the brew specs you provided, your dose is an average 26.2 grams. 54 x 26.2 is 1414.8 grams. One pound being 453.6 grams, that’s 3.12 pounds of coffee you should have brewed. Either Batdorf sent you two pounds, or two 12 ounce bags. In either case, something doesn’t add up.

But that’s a certain sort of unfair, on my part, to parse your words in this way. I’ll make a different case.

There’s a lot that goes into settling on optimal brew parameters for a given coffee. Brewing involves wetting, dissolution, and diffusion, so days from roast, packaging integrity, handling of the coffee, roast degree, roast profile, coffee density, coffee moisture content, bean variety, as well as grind profile, brewing dynamic, and other minor characteristics, all contribute to where optimal flavor emerges while adjusting your recipe, grind size, brew temperature, and brew time. This doesn’t account for brewing technique either. But you probably knew all of that.

Here’s something that it doesn’t appear that you know: A darker roast, a coffee that is roasted past second crack, is significantly different, from a brewing perspective, from one that is roasted before second crack. The definition of second crack is that vapor has escaped from the cells that comprise the coffee beans, and therefore the coffee particles. So every cell has what amounts to a blast hole.

Coffee roasted past second crack requires shifting to a different gear, of sorts. Brew times that are normally optimally 4 minutes should be adjusted to about two minutes. Brew temperature that is in the 200–205°F range should be brought down to about 175–190°F. That’s where you’ll find the best opportunity to make that coffee taste the best it can be.

Most coffee nerds (like you and me) don’t think we like coffees roasted past second crack, so we don’t find ourselves optimizing brew parameters for it. In fact, most coffee people tend to settle into a slot of brew parameters and don’t tend to move from there. Most third-wave fans, both home enthusiast and pros, in my opinion, grind their coffee too fine.

Now to be clear, I’m not claiming that understanding and employing the stuff I wrote above makes that particular coffee, or any other coffee, suddenly to your liking. You’re indeed entitled to your own opinion. However, I do think that it’s something to consider, if you’re interested in this sort of thing.

Anyway, take it or leave it, that’s my two or three cents on the matter.

Hey I’m Your Korean Dad! • proud immigrant • he/him • co-founder Wrecking Ball Coffee Roasters, San Francisco

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