Thoughts: Espresso Frustrations and Revelations
I apologize for the casual coffee reader. This post is a little more specific, and I don’t have it in me to break it down a bit more general this evening.
It wasn’t that long ago that my world was turned upside down by a James Hoffmann blog post. It’s silly to say that — I feel we all should be prepared to re-examine how we look at coffee after one of his screeds, but it was a particular post about pressure profiling (and specifically the modern espresso extraction recipe) that got my brain churning in my pitiful little skull.
I hadn’t done much by the way of espresso readings. Sure I’ve tasted more espresso in my life so far than your average Joe (sigh), but as to running the numbers and refractometers, I thought I had my palate calibrated.
Not quite. While I’m fairly sure I can pick out sour and bitter espresso like nobody’s business, what I didn’t count on was where the parameters actually lay. After reading that our espresso palates had been calibrated to a measly 16% ext. yield (spit-outtable by brewed coffee standards), I ran some of my own tests using Honey Badger espresso, a blend comprised mainly of Kenya, with a small amount of Brazil thrown in there.
Sure enough, after some refractometer readings and MoJo testing, I found that I was indeed only extracting 14-16%. Troublesome. While I had luck later with the Black Cat Classic on achieving a 17.89% ext., I found most of the knowledge I want to share with you based on those Honey Badger specs, and also stuff I found out today with the Black Cat Classic.
When looking at that base data, I wanted to rip my hair out. But then I got a sneaky idea. I’d been particularly faithful to the 65% brew ratio, but something made me change my mind: lengthening the brew formula. I’d let more water run through, therefore extracting more from that coffee using a lower coffee to water brew formula.
After running the test however, I could have kicked myself in the nads (or punched myself in the dick, if you may): the more water I ran through that shot, the less concentrated the shot was. That is, the lower the shot was in total dissolved solids (TDS). The lower the TDS for a brew formula, the more underextracted it is.
Now we all know that if we cut a shot too short, and have a 70-75% brew ratio, the shot will taste sour and underextracted (even though all of our shots are basically underextracted). The brew formula is too far off. You just can extract the amount you need to from that amount of coffee with so little water. But running a 45-50% brew ratio seemed to give us the other end of the spectrum — overextracted. Or at least, that’s what the recipe says it would be, if we were able to maintain a similar amount of TDS. Which we aren’t able too, since we’re using more water, meaning that the TDS will be more diluted. Meaning underextracted.
The actual science says, then, that both ends — higher and lower — than a 65% brew ratio will be underextracted. We’re getting sour or bitter, but neither is actually over extracted. Which ruins my thought process, and how I had looked at espresso in the past.
So this post is a bit of a downer. What did we learn? Espresso is futile. No, not really. Espresso is tasty and sweet, and probably a bit more on the sour/tart side than it should be. But it’s okay. We understand this now, and we can work to change it.
The first step is re-reading this post by James Hoffmann. The second step is to throw out any hard standards we had set in stone when it comes to espresso. The third step is to re-embrace all of those hard standards we had set in stone when it comes to espresso. The fourth step is to re-re-read that post by James Hoffmann. The fifth step is to take a deep breath, realize that we rule, and to make some delicious tasting goddamn espresso.
The biggest difference I found came in utilizing the finest grind possible, and manipulating this with a line-pressure preinfusion so that I didn’t choke the basket. And I will tell you, I was only getting 17.89% ext. yield at about 33 seconds. There is a way to responsibly increase the brew ratio without losing TDS. At some point in the scale, the more diluted TDS will have to bottom out, possibly around 5% TDS as the mass of the brewed espresso increases. My only fear is that this lands us right back at the traditional 14g for 2oz Italian espresso recipe that we’re so fast to decry.
At least we know that our bad tasting espresso are underextracted — both too little and too much water. If either of them were overextracted, we’d have an easy solution. That would mean we were jetting past our peak espresso target and would easily be able to dial it back. Which we know we’re not doing.
Which gives me one more thought — running the Black Cat Classic today (a bit fresh with a 3/4/2011 roast date, mostly Brazil, with some Tanzania), we were topping out at a 16% ext. yield with both the Synesso Hydra and the La Marzocco GB5. One strange untested variable was the density of the Kenya affecting extraction a few weeks ago, or the freshness of this roast affecting extraction today. Another strange, untested possible variable? Basket hole size. But that’s a different post for the future.
