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Nicholas Cho
Works at Wrecking Ball Coffee Roasters
Lives in San Francisco, CA
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Nicholas Cho

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James Hoffmann wrote a blog post, opening a poll about people's opinions/perceptions of brewing methods vis-a-vis different coffees. Just for fun, thought I'd repost my comment here.

James, my vote is: "No, and I do NOT think any brewer can brew any coffee well."

There are a few ways to approach this issue. First, you have to ask, is this a philosophical question, or a question of coffee science? Because ultimately, it's a question of relativism vs. absolutism.

Assuming one is more relativistic (and therefore answer YES to your main question), and believes that different methods suit different coffees, there's a separate question that you must ask: Is it that each method is ideally suited for a particular sort of coffee, or is it that a particular brew method will be the least-worst for the coffee in question?

In other words, is it that each method (and technique) is sufficiently flawed, each in different ways, and each set of flaws (or defects) results in a particular brew profile that is either pleasing or not pleasing to taste?

There's the sensory side of brewed coffee, in general terms of taste and such as they relate to brew methods, and then there's the more scientific approach: looking at the variables from coffee to coffee, in terms of density, solubility of solids, and diffusion rates within the coffee particles. This will absolutely vary from coffee to coffee, depending on all of the relevant variables.

I guess in conclusion, my long-form none-of-the-above answer is this: I believe that there is such a thing as "ideal brewing method(s)." I believe that some devices are inherently poor brewing devices. If using a good brewing method, I believe that you can exercise certain controls (grind, dose, water temperature, turbulence/flow, etc.) in response to the variables in the coffee, to a good result, without needing to go to an entirely different brewing method. However, if your coffee isn't "good," there are different tricks to make it taste more palatable than otherwise, including using inherently flawed brew methods and techniques intentionally.
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Agreed, the three possible answers were limited, like a skewed survey...
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19.1 is the new 20.0

The prior literature on coffee brewing tends to use mass units for coffee (grams or ounces), and volume for water (liters or fluid ounces, sometimes gallons or cups). Granted, you'll see teaspoons or tablespoons used sometimes, but none of those are really trying to be scientific.

Lavoisier's Law of the Conservation of Mass teaches us that mass is a constant. Volume depends on density. If density is a constant, then you can effectively treat volume as a constant in that particular case. In the case of coffee brewing, the density of water is not a constant. Water density decreases at higher temperatures. I have this particular web page bookmarked for when I need to calculate water density at a particular temperature:

So when you say "I'm brewing coffee with one liter of water," if you want to be precise and/or want to use this data to do some coffee brewing math, you need to know what temperature that water is. At room temperature, let's say 20°C (68°F), one liter is 998.2 grams per milliliter. At 93.3°C (200°F), it's 963.1 grams. The density decreased, and a given mass of water will expand in volume as it's heated. This is true, and undisputed.

This is a fact that Vince Fedele has pointed out to the world by integrating it into the ExtractMojo (and MojoToGo) software. Both pieces of software, therefore, uses mass for water instead of volume. If you plug in a volume measurement, it will use its own temperature-density calculator to convert it to mass, before it does its calculations. This a great thing!

So what's the problem? The problem is, with new units, you have to adjust the chart.

Everyone is still using charts that all read 18-22% as the Gold Cup extraction yield zone. But the 18-22% zone was developed with calculations using volume, not mass, of water. Therefore if you change the units to mass of water, since there's a density-based Δ (delta, or empirical change), you have to adjust the results of any calculations accordingly.

If using volume as your water number, the extraction yield zone of desirable taste characteristics "by the book" was 18.0-22.0%. Using mass and 93.3°C (200°F), the new corresponding zone is 17.2 to 21.1%. The "sweet spot," if you're trying to nail the middle point of that zone, is 19.1% extraction.

Therefore, 19.1 is the new 20.0!
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Thanks for the thorough answer, Nick.
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I've been trying to help make Google+ a good place for coffee-professional discussion by posting a lot here about coffee stuff that coffee professionals might get in to.

I've been told to stop. I've been told Google+ is sucks. I've never felt more like Lacey Chabert. I'm posting at Should I cross-post here, or just post there and post here that I'm posting there? Which option is more fetch?
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Enjoying the G+ forum, though any forum would do. A blog does seem more a place that the author owns. I recognize that Google owns this post, but it feels more conversational here.
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Nicholas Cho

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Recipe vs. 5-D Technique

There’s been a strong trend in specialty coffee over the past few years: recipe obsession.

It does make sense. Before around 2008 when the manual brewing revolution gained significant speed, espresso and filter coffee-making was mostly only about recipe. Grams of coffee grounds, a certain grind setting on a certain grinder, seconds of extraction, throw weights, full-batch or half-batch, etc. You prepped the coffee and equipment for brewing, inserted the portafilter or brew basket, pressed a button, and stood back while observing the output (sometimes).

But “manual” means manual, and what used to be lock-and-load is now managed from beginning to end. Going from automated to manual really means one thing: now you have to worry about technique.

However, the vast majority of the information being exchanged is not about technique, but about recipe.

It makes even more sense. Recipe information is easy to articulate, almost by definition. On the other hand, it’s almost impossible to convey anything meaningful about technique in a 140-character tweet. We shouldn’t fall prey to the fallacy that what’s discussed out there online among coffee professionals and enthusiasts is what’s actually important in and to coffee. Or to anything that matters in life, I suppose.

I’ve mentioned this a few times before here and there, but maybe it’s worth repeating: manual coffee brewing techniques require the brewer to essentially have to think in five distinct dimensions. The 3-dimensions of physical space, the fourth dimension of time, and the fifth dimension of kinetic energy. Yeah, really. Those are the five dimensions you have to work in, applied to best extract the best flavor from the coffee while mitigating negative flavors.

Oh yeah, plus the recipe.
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Perfect Coffee?

At last year's SCAA annual Expo, the keynote speaker was George Ray McEachern, a professor of horticulture at Texas A&M University (, focusing much of his research and study in wine. He used a particular phrase during his speech which absolutely fascinated me, especially as we often compare coffee and wine: "Perfect wine."

He kept saying stuff like, "We (in the wine industry) used to have problem, but we fixed it by , and now the wine is perfect." There's an almost visceral reaction that follows a comment like that. "Perfect?" How could he possibly be so obtuse as to declare wine to be "perfect?" Clearly there are different quality levels in wine, not every wine scores a 100 points (on any scale), and there is obviously much improvement that is still plausible and possible in wine, at every step in the process. Just like coffee!

But that's not what he means. What he means is essentially that wine is now mostly defect-free. Even low-priced wines, while perhaps not the most earth-shattering in flavor, exhibit all of the baseline qualities that what you'd call "good quality wine" should have. Processing-related defects are mostly non-existent. Technology and technique have discovered the sources of the defects, and technology and technique have resolved them. Hence, today, you have, perfect wine.

I had never thought of it that way before, but while it takes a little bit of shifting-of-gears mentally, it really makes total sense. In our world, where a 94-point score makes you wonder what's wrong with it that it's not a 100-point score, "perfect" is impossible. "Perfect" is a Holy Grail of sorts, never to be achieved but forever to be pursued.

Perfect wine does not mean that it will all score 100-points. Defect-free is perfection of a critically-important sort, but it still allows for different quality levels within it. You can have a Honda Civic and a Mercedes S-Class, and if both are mechanically perfect with no defects whatsoever, you could call them both perfect. It does not have to mean that they are equal in quality.

So obviously, the next question becomes, what is "perfect coffee?"

Right away, even if one were to accept the idea of perfect wine, many will resist the idea of "perfect coffee." Indeed, despite all of the similarities between coffee and wine, they are also very different. Wine is commonly referred to being about 30 years ahead of coffee in development, and the growing and processing of coffee has much farther to go before we can declare coffee to be "perfect." But that's not to say individual coffees can't be perfect.

Grow perfect coffee. Process perfect coffee. Source perfect coffee. Roast perfect coffee. Brew perfect coffee.

For us in the consuming-world, it starts at sourcing. There is still a great deal of defect to be found in green coffee supplies of renown specialty coffee roasters. Defect must be eliminated from what you do. Roasting defect must be eliminated. Brewing defects must be eliminated. Every time a specialty-coffee professional accepts defect without identifying it as such, it holds the industry back.

This will, somewhat obviously, require for specialty coffee professionals to first learn to identify defects in green coffee, in roasting, in roasted coffee, in brewing, and in brewed coffee. But often, someone will allow over-ferment and instead call it "fruity." Someone will have roasted coffee with scorching and tipping and call it "tobacco-finish." Someone will taste an over-extracted coffee and call it "complex." Each time this happens, it holds the industry back.

It really can be perfect.
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Is Green Coffee > Coffee?

(long post, cross-posted from

Why the obsession with green coffee?

Let me rephrase that. Why such relatively-little attention paid on the other stuff in coffee?

Off the top of my head, let's make a list of ten major distinct areas directly involving coffee. Note: I'm intentionally leaving out important social, environmental, or ethical issues here. Let's just look at the coffee for a moment:

Coffee growing & cultivation
Coffee processing
Export/import of coffee
Cupping & Quality Control
Retailing & Service

If you're tempted to, don't pick my list apart. That's not the point.

The point is, how much innovation or "progress" in each of these ten areas have we seen in the past, let's say ten again... ten years? Again, let me do this off the top of my head: on a scale of one to ten, for each one, let me assign a number rating the amount of advancement I've observed on a significant scale. 10 is high, 1 is low. I'm also going to re-order them in order of highest to lowest:

Export/import of coffee : 8
Coffee growing & cultivation : 8
Coffee processing : 8
Espresso : 6
Retailing & Service : 4
Brewing : 4
Cupping & Quality Control : 4
Grinding : 3
Roasting : 2
Packaging : 2

Looking back over my ratings there, I already want to re-think some of those, but I won't. The specifics aren't important.

I've been thinking a lot about why this is the case. Why the dominant focus on coffee-origin issues? There's the obvious: coffee is grown, cultivated, processed, and exported from some of the poorest countries in the world. A major (if not majority) part of the limitations in coffee is due to just how much improvement potential there is in origin-work. It's super-important work. This post is not in any way calling that into question.

But what about the low-rated stuff?

SCAA has a Symposium, now in its fourth year. There's a tiny bit of consumer-marketing stuff at times, but it's dominated by origin-specific content. The Global Coffee Quality Research Initiative (GCQRI), now renamed World Coffee Research, is also origin-focused. In Europe, you see ASIC, but the consuming-world content included is not the sort of stuff that pushes forward on the low-rated stuff up there in my list. It's more mass-market company oriented information.

Perhaps those low-rated elements simply need less improvement, either because they're already high-quality, or because they're less important. Maybe. But I have some other thoughts. Three thoughts to be exact:

1) The "Helping The Farmer" Trap

The coffee farmers need our help. This is true. It's also something people say far too often without any meaningful understanding about the actual farmers, what help they need, and how that relates to what you're doing.

I might expound on this topic some more in the future, but for now: I think "helping the farmer" is definitely related to good intentions. I also think there's some economic imperialism, subtle and inadvertent racism, and American/European exceptionalism involved. Okay, that's some heavy shit I just threw down there, and I'll do my best to get more into this topic in a future blog post.

How this relates to this particular post is that "helping the farmer," in its myriad manifestations in our industry, gets the bulk of our focus because in many ways it's the quick and easy answer to everything. "Quick and easy" is a relative term. I guess it begs: What's not quick and easy?

2) What's Not Quick and Easy

Of all of the consuming-world stuff in the list, the highest-rated is espresso. There have been undeniable advances in espresso over the past decade. I believe that the reason is two-fold: it's because of the World Barista Championship (and its repercussions throughout the specialty coffee world), and because enough people were able to admit that their espresso could be better.

How does roasting improve? Perhaps first, you have to identify poor-quality roasting. Identifying poor-quality roasting, in our too-small fishbowl of a specialty coffee sector, is pretty much the same thing as identifying poor-quality roasting in specific companies.

You know what I'm talking about. Anyone reading this blog post who has been in the industry for more than a couple years has talked shit to someone about a peer-group coffee company's roasting, baristas, roast or espresso or filter coffee quality, etc. But this criticism, no matter how confident you might feel about its merits, occurs in private.

"I think Wrecking Ball's Yirgacheffe single-origin espresso that I tasted last week had clear indications of scorching and tipping. You should check it out, taste the coffee, and find out what Trish is doing to make that roasting defect happen." If this were true (which it's obviously not), and we lived in a world where such a statement was not insulting, risky, and bridge-burning, there'd be a ton of learning to be had by all. How often do I have a hand-brewed cup of coffee at a renown coffee shop, and having observed the barista at work, could give 5 easy tips to make that coffee taste better? Sure, I COULD, but I never would. To do so would be a slap in the face of friends and colleagues and a major violation of the unwritten social contract we live under.

Criticizing origin-related stuff is easy. They're poor farmers. They don't know any better. Criticizing each other, that's really difficult, if not impossible. But thankfully, public disparagement isn't the only way people learn. Too bad we don't have the other way either.

3) No Coffee Education

There is no tradition in our industry of institutionalized coffee professional education. There is no culinary-school degree equivalent in coffee. Save a few isolated botany-related programs, there is no university education to be had in coffee. World-champion baristas can have worked for 10 years in coffee, and they likely don't know something as fundamental as the chemical process of de-esterification of chlorogenic acid or specifically why coffee particle "fines" happen during grinding.

One might object, "But many successful chefs didn't go to culinary school!" That's true. But they live in a world where culinary school exists, and decades of traditions have established fundamental concepts and principles, and a culture and history that is the foundation of an industry. Some chef may have skipped culinary school, yes, but there was something there that they essentially tested-out of. They paid their dues and learned all if not most of that stuff a different way.

Our industry is full of creative, passionate people. That's for sure. It's also full of college drop-outs (like me). It's full of people who work at a coffeeshop for two weeks and read a little of James Hoffmann's blog and then they're out droppin' knowledge on everyone who can't run as fast as them. It's full of people who bought a 3-pound coffee roasting machine but have little to no training on how to roast coffee and get interviewed by the local newspaper and are now deemed the town's coffee expert.

Someday, hopefully not too far in the future, we'll have some real coffee education. Yes, there are multiple places in the U.S. that teach "coffee business," mixing basic skills and information with business and management training, but even those are at the most 5-day programs. I'm talking about something like a 2-year accredited degree or certification program. What would our industry look like if there were programs like that offered in a few places around the country and around the world? I would love to find out.

There needs to be a lot more researched, learned, taught, and improved in coffee varieties and agronomy and processing and such. Absolutely. But as I continue to meet baristas all over, I see passionate and intelligent people who are absolutely starved for some real learning that would support their careers. SCAA education is the best stuff out there right now, and it's improved by leaps and bounds over the past 2-3 years, but it too still has a long, long way to go; and even then, I don't know that this is a problem that SCAA is best equipped to solve. I think the market for formal coffee education needs to be developed. The conditions are more ideal for this sort of development in Asia than in North America or Europe, but that too is for another post someday.

So yeah. More focus on that stuff that needs more focus. More teaching. More learning. More skills development. More sharing. But over it all, more professionalism. But it'll take one little baby step at a time. Etc. Etc. Blah-blah-blah. How are you supposed to end these blog-post things, eh?
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+Nicholas Cho It's interesting - I'm pretty new to all of this, and I'm not a coffee professional, but one thing I'm noticing about the fishbowl-sized world of specialty coffee is that there is a ton of passion and inspiration involved. In point 3, when you talk about coffee education and what it could mean, it reminds me of little things like Disloyalty programs and even the banter I see on G+ and twitter between roasters and companies. It's incredible. Here you have "competing" businesses collaborating and getting excited about the same thing because they want to share it.

I've been really impressed at how different the business model seems - granted, I've not been behind the scenes, but still...

What I'm trying to say relates to your first point, about the "helping the farmer" trap and all of the imperialism, racism, etc. that potentially goes into that: you're probably right, and I think that stuff shows up in a lot of areas of life, but from what I've seen so far, people like you who make up the specialty coffee industry, and really set it apart are changing that. If any industry could break the mold and truly help large groups of people, improve processes and techniques, and at the same time educate and teach, it's the specialty coffee industry.
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Water Torture Part 2

So thanks to coffee ingénue +Ben Kaminsky, I got my water measured.

To recap: a couple weeks ago, our water was reading at about 40-50 TDS (total impurities), the 'book' says about 150 ppm TDS is ideal for brewing coffee, and my water is now reading about 140-150 ppm TDS.

Ben measured my water to be at 8 grains of hardness.
hardness = Calcium Carbonate (CaCO3) content
1 grain = 17.1 mg/L (mg/L and ppm are about the same)
8 grains of hardness = 137 mg/L CaCO3
"the book" says 3-4 grains (51-68 mg/L) of hardness are ideal for brewing coffee.

So my CaCO3 content is really high. CaCO3 is an acid buffer, and sure enough, the coffee tastes like you magically removed most of the pleasing acidity. I guess I'll use bottled water again until the utility goes back to producing harder water. Apparently our water utility has changed where the water is being sourced (this sort of thing is very common for high-population areas).

At this point, I have more questions than before:
Why does "The Book" say 3-4 grains is ideal? Why not lower, or no CaCO3?
Why is it 150 ppm TDS ideal? How much of this is a valid rule-of-thumb, and how much of this is a lowest-common-denominator?

I'm finishing typing this up as I'm waiting for a couple cups of coffee to cool. As an experiment, I brewed them with distilled water. I've also reached out to some of my water-expert colleagues out there. Stay tuned, more to come.
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Inconclusive. I'm going to do some more controlled taste-stuff now that my taster is back from her trip. :-P
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coffee steward
  • Wrecking Ball Coffee Roasters
    spittoon boy, present
  • murky coffee
    janitor, 2001 - 2009
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San Francisco, CA
washington, dc - redwood city, ca
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