Bitter Press

Contact Time vs. Extraction

There are five basic ways to affect extraction of coffee.

1. Dose/Ratio — the more extended the coffee to water ratio, the more extraction you’re bound to get from the coffee.
2. Grind — The finer the grind, the more surface area of coffee is exposed, the more extraction you’re bound to get from the coffee.
3. Water Temperature — Certain desirable solids need higher water temperatures to dissolve, and water that’s too cool will prevent extraction to the desired degree.
4. Contact Time — The longer the contact time between coffee and water, the more extraction you’re bound to get from the coffee.
5. Agitation — Agitating coffee will promote quicker extraction, somewhat due to re-exposing surface area of coffee particles that have settled during the brew process.

These are obviously up for debate. And they might be a little off in their explanations for those who want absolute specificity or are prone to splitting hairs. 

What’s been bothering me lately, however, is the correlation between contact time and extraction. Monitoring contact time very specifically isn’t just a way to promote great consistency, it’s also a way to monitor extraction. 

This is especially true with brew devices like the Hario V60. Because of the large exit hole in the V60, the brew device requires a finer grind than most other pour-over brewers. Because of the finer grind, any shift in contact time larger than ten seconds will greatly affect extraction. Therefore, when brewing with the Hario V60 and using a continuous pour, one knows that a brew time of around 2:00-3:00 minutes is generally going to land within a good extraction for 300-600g of brew water. When brewing with 415g of water, however, I know that I need to land right at 2:15-2:25 in order to land at the desired extraction yield. 

Coffee brewing becomes fairly easy, then. Adjust grind until you reach desired contact time for selected brew ratio. But this is a very specific recipe. It requires exactly a 45 second bloom and 45 second pour speed, and exactly the right grind setting to achieve the right extraction. Things get more difficult when you look at not just other pour-over brew devices, but also different pour-over brew methods.

I don’t want to pretend to know a lot about coffee. I know a good bit, but I’m no scientific researcher. Most of my knowledge is pried and cobbled together from minds much more brilliant than my own. However, I do have two things going for me: obsession, and a quick learning curve. 

This style of thinking has geared me towards using a refractometer and MoJoToGo software to help monitor extraction rates in coffee. It’s a set of empirical data that can been used and tracked, and generally correlates with good tasting coffee. 

When using a refractometer to monitor extraction, one becomes very aware that when looking at extraction data, contact time isn’t as much of a set absolute. If looking directly at numbers, one can achieve higher extraction rates at shorter contact time by increasing agitation greatly and using much finer grinds. That doesn’t mean that coffee will taste very good, however. 

One thing I’ve found, on a personal preference level, that coffee when brewed through a pour-over brew device other than a Hario V60 tends to taste best with a coarser grind and a longer contact time. But not only do I generally prefer the taste of that coffee, I also appreciate the fact that with a coarser grind, I don’t have to nail my contact time to a perfect 10 seconds. Due to this concept of brewing, and my desired yield amounts, I’ve been brewing using 155 and 185 size Kalita Wave brewers. 

Here’s where it gets tricky. Most people will tell you that with a Kalita Wave brewer, you should aim for 3:00-3:30 contact time with the coffee. With this ballpark time, you’ll generally be within the ideal extraction rate. But when I attempted to start brewing with these two sizes, I found that I was having a hard time getting my brew time to extend to 3:00. My brews were consistently ending around 2:15-2:30, and no matter how slow I tried to pulse pour my brews, the coffee would always exit through the filter too quickly to even get close to 3:00. 

The coffee had been tasty, however, at 2:15-2:30. But I knew that those weren’t the desired contact times. So I began grinding finer, in order to prolong the brew time. And like you’d expect, I was able to extend the brew time longer. But I began consistently over extracting the coffee, and was drinking terribly astringent coffee every morning based on the fact that I liked the brew time. After bringing out a refractometer and monitoring my brewing again, I once more went coarser in grind and came to accept that my shorter brew times would be tastier than longer brew times that over extracted. 

In the meantime, my Hario V60 brews at work were still tasty and delicious at 2:15-2:25 and measuring desired TDS and extraction yield percentages. 

For months, my brewing and patience had been put to the test. I knew I was getting tasty coffee, but it wasn’t as tasty as I wanted it to be. But I had another lightbulb go off in my head. All this time, I had been trying to achieve a contact time that I normally only reserved for 24oz brews. Of course, the 3:00-3:30 advertised brew time for the Kalita Wave was also usually reserved for 24oz brews. My wife drinks tea in the morning, and when I brew coffee, I brew coffee just for myself. There’s no way I’m going to put down 24oz and feel good later on, especially when my job centers around coffee every day. So I had been targeting 12oz brews on the 155 size Kalita Wave, and 16oz brews on the 185 size Kalita Wave. 

Common sense would decree that larger amounts of coffee will of course take longer to brew for pour-over brewers. The physical act of pouring a larger amount of water will always take longer than smaller amounts of water. Maybe I had been chasing a dragon.

Still, there was something about the those longer extraction times with coarser grinds. 

And then I got to thinking this morning: if my coarser grind brews landing at 2:30 are giving me desired extraction yield and TDS rates, then if I ever wanted to mimic the 3:00-3:30 contact time, I’d have to adjust my grind even coarser to line up the contact time and grind size in order to avoid over extraction. 

Which, seemingly, was an impossible task. But I had learned a few things. My standard bloom time is 40 seconds. But I found that when brewing with Wave, the 40 second bloom time allowed the water to pass through the coffee much more quickly, much like pre-infusion with espresso. So I shortened the bloom to 30 seconds. Not only did the shorter bloom time keep me from over extracting, it also helped prolong the total contact time by somehow flattening the coffee bed further into the corners of the brewer and choking off the airflow and water flow through the holes in the bottom of the brewer.

Also, I found that the Kalita Wave filters at the top of the stack tend to be more squished, and don’t rest as tightly to the sides of the brewer as the ones from the bottom of the stack, which tend to be more flared out. 

Lastly, it seems that pouring in such a way that keeps the bed very flat during the first few pulses tends to choke the flow in a way that helps prolonged brew times. And with that in mind, today’s 34g coffee, 525g H20 brew clocked in at 3:15. It was dee-licious. 

The real issue here, however, is why? I know that some folks out there have put forth the idea of solubles on the edge of the coffee particle versus solubles in the center of the coffee particle creating different flavors. But with a finer grind, those internal solubles would be then surface solubles, and would extract just the same as a prolonged brew time with a coarser grind would eventually extract those center solubles. 

Or is it the process of slowly extracting from the outside in that creates more depth in flavor? Perhaps, like a time dissolving capsule, there’s a certain order to the way we want our extraction organized. 

Another major issue here is water quality. Water with a high hardness or high TDS of mineral content generally needs longer contact time to even get close to the desired extraction yield percentages. I know that when I was in LA brewing coffee, even with finely tailored filtration systems, the water clearly was extracting much differently than the water in Chicago. 

Which sucks. Because that means that any chance to really describe extraction times to people across the country is severely stunted by the varying degrees of water quality. Therefore, any time we give out contact times for brewing, we also need to publish the exact water make up numbers with it. And since grind size and and contact time aren’t perfectly married, maybe we need to publish the average micron size of grind particles for desired grind level. 

It’s more than just a rabbit hole. It’s a goddamned cave system. Which is, I guess, whatever. The goal is to be happy when you’ve achieved tasty coffee. A scale, a thermometer, and a timer will help you brew that tasty coffee consistently. Maybe that’s the extent that we can really examine extraction quality. 

What do I know? I have a degree in Fiction Writing. 

Re-vamped Bitter Press

I found myself in quite the pickle just the other week. If you Google my name, you’ll find a bevy of Internet skeletons dating back to when I was just 15 or so. If anyone knows the danger of being called out for having bad or outdated info published on the web, it’s me. 

So when my friend told me that he was probably going to ditch his hosting, I thought I would just let Bitter Press die. It had been a long, long time since I updated it, and there are plenty of skeletons in the archives. 

Then I took a look at the number of hits it had built. And I realized, very worriedly, that people were still reading Bitter Press. Like, regularly. Like, a lot. So I decided I could do some more good by pushing the domain over to a free Tumblr account, and keep the information light and airy.

This means all the old posts are going to lose their photos. It’s true. What started as a very photo centric blog is now going to be much more text based. Part of it is just that the photos didn’t port over like I hoped they would, and uploading them again would be a chore. Mainly it’s because I don’t believe that most of what was up there really would do anyone any good. 

So I’m tagging all previous posts as “OLD AND OUTDATED” to let people know that they should check publishing dates before processing the information provided, but I’m keeping the posts active and up on the blog for the time being, because I think there is some worth in looking back at where we came from. 

I’ve been itching to do a bit more writing again recently, and I think I’m moving a bit further away from straight writing about coffee brewing, and more towards essay style posts. We had a preview of that in the post titled “The Work Vs. The Weight.” 

Stay tuned.

Essays: Success Vs. The Work Vs. The Weight

I recently wrote a piece for Fresh Cup Magazine about the role of the modern barista, with a bit more attention paid to the business side of things. And while I’m of course proud to have another piece of writing published, I can’t help but feel that it doesn’t exactly address everything I had on my mind.

One piece of the article was about finding personal fulfillment working in the coffee industry as well as being able to support yourself financially. And it’s that personal fulfillment clause that brings up two concepts that I abstractly refer to as “Success” and “The Work.”



Namely, what qualifies as a Success in the day to day operations of a cafe? We’ll get to The Work in a moment.

I’ve received my fair share of criticisms for my full embrace of the refractometer and the Extract MoJo or MoJoToGo software, as has anybody who’s come out either for it or against it. But my use of the equipment and software comes from two separate places: my own want, desire, and need to brew myself the best cup of coffee I can every morning, and my own want, desire, and need to be able to understand what happens when we brew coffee to the best of our ability so I’m able to teach people to the best of my ability how to brew a good cup.

In a cafe or coffee bar situation, however, does a 19% extraction yield at 1.45% TDS automatically be declared a success? Well no, but this isn’t news. We’ve talked about how it’s a road map, not a treasure map. It’ll help you find where you want to go, but there’s no giant X with a dotted line leading you to it.

Success, for me, is defined as serving or being served a really, really tasty cup of coffee every time one is brewed. Success is impossible by that definition, so I suppose we could stretch it to Success as being defined as being served a really, really tasty cup of coffee most of the time one is brewed. And to me, understanding how to get to that point really involves learning everything you can about how to brew coffee, even if it isn’t your natural approach and goes against your coffee philosophy. It means doing The Work.

Now, The Work to me is the big one. Success is what we’re striving for, but I think that Success is unattainable without doing The Work. What is The Work? Eh, that’s sort of a gray area. The Work is a concept I sort of borrowed from the lyrics of the Sweeney Todd musical. I’ve never seen the show, but I heard Terry Gross interviewing Stephen Sondheim about it, and they commented on a song in which Todd is singing about his plotted revenge, he finishes the song “Epiphany” by saying “But the work awaits! I’m alive at last! And I’m full of joy!”

Macabre, for sure. But the concept he speaks of: I know it. He’s referring to the fact that he plans to murder just about anybody so that he can practice his skills at throat cutting, so when the opportunity to exact revenge arises, he’ll be ready. That’s The Work.

I don’t advocate killing anybody, for realsies, but The Work is real, and it exists for all of us. If you want Success in the financial industry, you do The Work. I don’t know what qualifies as Success in the financial industry, and I wouldn’t know what The Work is, but I know it exists.

For us humble coffee folk, doing The Work means exploring all possibilities, putting in the time and effort to brew coffee at any given chance, and to always be expanding on the knowledge base you draw from so that you’re ready when you’re attempting to achieve Success.

Recently, I’ve been trying to figure out how to brew with a lever espresso machine. I’ve been pulling some nice tasting shots from it, and asked a co-worker for her opinion. She didn’t like the aftertaste the coffee was getting, and told me I should probably just pull the cup sooner as the shots were running long. I insisted that any sort of aftertaste was the product of the machine running hot and the water boiling from the groupheads (heat exchanger, what’re you gonna do?), and that cutting the shot short would only create underextraction. I soon realized, however, that I was being foolish. I was searching for Success, but I wasn’t willing to do The Work.

To sum it up, I found a better espresso—pulling the cup helped get away from some last second blonding, and a slightly shorter brew time put the coffee in less contact with the overly hot water, toned down some of the aftertaste that was coming out. And I wasn’t sacrificing much brew volume, either. In fact, when I brought my scale out, my espresso volume was much more on target anyway.

This is The Work. It requires staying open to any and all suggestions, and putting them into play to achieve better brewing. I recently changed my Aeropress method, as well, after having great coffee at Tim Wendelboe’s shop in Oslo. I had been doing inverted only, on a firm stance that you lost too much coffee through the filter if you brewed right side up. But the Aeropress I saw at Tim Wendelboe’s brewed a really great cup, and at home I’ve been brewing the best Aeropress I ever have using a similar method to his.

Doing the Work means, from time to time, setting aside my established preference for knowing the extraction data behind a cup of coffee, and seeing how that stacks up to other coffees I’ve brewed or tasted. It’s almost, in a way, an active form of trying to humble yourself.

So if The Work is practice to achieve Success, then what’s The Weight?

Ah, The Weight. Not only is it a great song by The Band, but it’s something I see come out in some of the finest coffee brewers I’ve ever met. The Weight is the nervous tic, the creeping guilt, the dread of knowing that you’ve not been doing The Work. The Weight is what you feel when you sit down for your morning coffee, and you’ve somehow botched your brew. Even thought it’s just coffee you made for yourself, you’re almost ashamed. It haunts you for the rest of the day.

It’s The Weight.

These are just abstract terms I’ve applied to feelings and sensations I’ve experienced when it comes to coffee, but I’m fairly certain they’re fairly universal for most coffee professionals. It’s the kind of thing I identify in most people who’ve ever served me a great cup of coffee. Basically, it’s the drive to succeed that anyone in any industry needs to pursue their own Success. I’m not sure what to do with it, but I guess like therapy, talking about things helps push towards breakthroughs, and maybe I’ve just been feeling The Weight a bit more lately.

I suppose that just means one thing: time to do The Work.

Let’s Talk About TDS, and MoJoToGo’s Coffee Lite Mode

What makes a cup of coffee taste?

Not taste good, not taste bad, just… taste.

Polyphenols! And acids! And fats! And carbohydrates! And… well, who knows. Plenty of people, actually, but how much of that is relevant to making a good cup of coffee? Dictation of taste comes down to two main factors that we can measure: extraction yield, and total dissolved solids. Or, if you’d like — how much we’re extracting from the coffee, and how much of the total brew is made up of those solids we’ve extracted.

Coffee is made up of around 30% soluble solids. When we talk about extraction yield, we’re talking about how much of those 30% soluble solids we’re dissolving into hot water to create coffee. It has been generally established that 19% extraction yield is where coffee tends to taste the sweetest.

The overall drink that we look at as brewed coffee is about 98.5% water. It’s that small, critical amount of total dissolved solids (from hereon referred to as TDS) that dictates the concentration of the coffee. And while 19% has been established as the preferred extraction yield (the overall accepted range being around 18-21%), TDS is a preferential metric. As long as you’re hitting that extraction yield that we’re looking for, any range of TDS from 1.2%-1.7% as an extreme example will taste sweet. Often thought to be fairly regional according to preference (Specialty Coffee Association of America preferring around 1.3%, Specialty Coffee Association of Europe preferring around 1.4%, Nordic Coffee Association preferring around 1.5%), TDS has been fairly ignored in this past year or so of heavy extraction measurement in specialty coffee — extraction yield has been the main concern.

But in this Twitterverse of knowledge transfer and recipe sharing, we never talk about what our target TDS is. And this is mainly because most of us don’t know what it is. We look at a coffee to water recipe and brew with it until it tastes sweet, adjusting the grind, temperature of water, etc. But knowledge of what the target TDS range for a shared Chemex recipe greatly determines what recipe we’re actually shooting to use.



If I told you to use 32 grams of coffee for 450 grams of water at 200ºF, you could take that recipe and brew with it. But if you knew that this recipe relies on 1.60% TDS in order to reach a 19.61% extraction yield, you’d have a better advantage towards hitting that extraction yield. You’d know that a longer contact time, or slightly finer grind is going to assist you in getting a higher concentration of soluble solids in the cup, possibly more advantageous than just hoping your standard grind/contact time would be suitable.

Our industry Gold Cup Standard relies on using 60 grams of coffee for 1 liter of water. But this recipe assumes about a 1.3% TDS. Whenever I see someone balking at a 70 gram per liter ratio and saying it’s wrong, I want to sit them down and try and talk about extraction science. This isn’t a “bad’ or “wrong” ratio. It’s a ratio that assumes a higher TDS concentration in order to achieve a tasty extraction yield.

Now then, we do have a slight issue when we use 70 grams per liter, and one doesn’t adjust things like grind size or contact time. If we use a higher coffee to water ratio and don’t manipulate our brewing variables to accommodate it, we end up underextracting the coffee.

Sure, this is a danger, but so is using too little coffee. Many times people have tried to maximize their coffee to water ratio and use as little coffee as possible to achieve a tasty cup. But what this means is that the recipe necessitates a low TDS in order to achieve a tasty extraction yield. Otherwise you run the risk of overextracting the coffee and bringing out the bitterness that overextraction yields.

So if we aren’t looking at, discussing, or acknowledging the power that TDS has over the recipes that we’re using, we’re cheating ourselves out of one half of the measurable constants that we have readily available to us to use as a discussion basis.

And this isn’t even considering the affect that TDS can have on the flavor of the coffee. With a low TDS, the flavors we’re looking for — say pear, baking spice, and hazelnut — may be harder to pick out. With a high TDS, we’re cramming those flavors into the coffee to the point of being very intense and sometimes overlapping to a detrimental point.

That isn’t to say you can’t achieve a sweet cup at either end of the spectrum. It’s totally possible. What it means, however, is that TDS is what we can use to manipulate the flavors of the coffee that we’re presenting. Or the brew method we’re using to highlight those flavors. Personally, I’m a bigger fan of a 1.4% target TDS range for V60 brewing in order to bring a lingering space between flavor notes, while a 1.55% target TDS for an Aeropress seems to bring a punchy flavor explosion to the palate.

Yes, it’s all preferential. That doesn’t mean we shouldn’t talk about it. In fact, it’s what we need to talk about. Extraction yield is an introduction to coffee tasting. But if your coffee is tasting sweet, we need to move past that quickly and talk about why it’s tasting sweet, which is a combination of the amount of coffee used, the amount of water used, and the total dissolved solids in the cup — all of those factors are what we use to determine the extraction yield.

One thing I’d like to mention to round out this discussion is the availability of an iPhone app called MoJoToGo. It’s the portable version of ExtractMoJo, a software suite designed to help us measure our extraction yield in conjunction with a coffee refractometer that gives us that data by calculating coffee in, water in, and total dissolved solids.

The application’s $30 price tag is pretty reasonable for being able to scientifically interpret data in terms of extraction, but I found another use for it when at home. I used MoJoToGo to compute basic brew formulas for all my brew methods. Start with a target TDS, plug in the amount of water you want to use to dictate how much coffee you want to brew, and slide along the amount of coffee to use until the extraction yield slider hits your preferred target. It’s simple, easy, quick, and helps interpret new coffee recipes that we’re sharing.

Now the application also has a Lite Coffee mode. It’s only $5, and has a few things disabled — like the TDS slider, but works the exact same way. You’re able to choose your target TDS from the preset preferences, plug in your water data, then slide your coffee data until you find the right extraction yield. There’s even the ability to add a bunch of correlating data to your recipe and email it off to other people.

Okay, it’s a bit of a shill — but I like the program a lot, and it has really, REALLY helped me understand the science of coffee extraction and manipulate the coffee recipes I’ve been using to develop the tastiest coffee I’ve ever brewed at home.

What it represents, however, is a way for small shops to help introduce themselves to better recipes and smarter brewing. If you don’t have the budget for a refractometer yet, Lite Coffee mode will give you most of the tools you need to develop a good extraction yield by taste. Now some people may have issues with the software and with discussing coffee only in terms of extraction yield and TDS. A lot of folks are decrying this scientific pursuit and only want to talk about taste.

The issue is that when we talk about taste, and subsequently dialing in a coffee by taste, we’re ignoring the fact that we’re manipulating these two variables in order to find a taste we like. Why not eliminate the guessing work? We’re still dialing in by taste, but if someone’s offering you a GPS device for navigating a city you think you’re pretty familiar with, you might as well take it to help you plot your course. It’ll help you remember that Madison Street is a two way until you hit Dearborn, and then it turns into a one way, and you have to circle around the block in order to get where you want to go. And believe me, $5 for a GPS device is a pretty good deal.

For full disclosure, I’ve had many conversations with Vince Fedele of VST Software, who invented MoJoToGo, and helped develop the coffee refractometer. He’s been a great resource for coffee discussion, but we don’t always see eye to eye on a certain number of coffee brewing topics. It’s because of my enthusiasm for using the iPhone application as a recipe resource instead of just as a measurement tool that Vince asked me to help test the Lite Coffee mode.

You can take that how you will, but in no way did my involvement in testing the software affect my eagerness to write about how helpful of a program it is.

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.

Essays: Unintentional Success, featuring The Aeropress (With Guest SpotBy Coava’s Disk Filter)

The best brewing devices are conceived, most of the time, for the wrong reasons. Siphon brewing was invented mainly because vacuums were just discovered as a principal of physics, and coffee was also in vogue at the time. The Chemex was created with a main focus on the thicker paper filter. Cafe Solo was invented because the filter on a french press is hard to keep clean and can trap oils in there.

No one knew that siphon brewing was commendable for it’s supreme temperature stability. No one knew that the conical shape of the Chemex would help us re-evaluate extraction and brew times. No one knew that the onus of the Cafe Solo is the slope of it’s base, which helps naturally filter the coffee grounds and gives an extreme amount of control over the agitation throughout brewing.

Which brings us to the thorn in my side, and shining star as of late, the Aeropress. Invented by a frisbee designer, rumored to be using grocery store coffee to test it, the Aeropress is a simple pressurized brew chamber with a thin paper filter used to make a concentrate, which is then diluted by adding extra hot water. The box calls for the coffee to be brewed at temperatures around 175 degrees Fahrenheit in just about ten seconds. Everything about this, to the average coffee person, just sounds wrong.

That’s because it is. Diluting coffee ruins the natural body of brewed coffee, and coffee brewing is a matter of extraction — coffee extracts best at temperatures hovering around 200 degrees Fahrenheit. Poor temperature management is one of the number one reasons that people have given up on the Clover. And ten seconds? Even with a nine bar pressure and a full tamp, good espresso takes at least twenty.

Because of these circumstances — and the Aeropress’ great commercial success — it has always been a stinky turd in the corner of my mind. A charlatan’s snake oil. Sure, I’d had good cups off an Aeropress before, but wouldn’t supporting the Aeropress financially mean that I’m somehow supporting the dissemination of poor coffee making decrees?

The answer is, no. But that’s mainly because I stole my dad’s Aeropress that he never figured out how to use. And there’s a good chance that you, too, can snatch an Aeropress from a friend or relative that purchased one on a whim. But that’s not really a practical or useful way to think about things. Let’s try that again. Wouldn’t supporting the Aeropress financially mean that I’m somehow supporting the dissemination of poor coffee making decrees?

No. And that’s because there’s a large enough vocal contingent out across the Intarwubbs that are helping to promote safe, practical, and correct uses of the device. And here’s another one. I encourage you, as well, to be one more, too.

It’s all very simple. The boon of the Aeropress is the immersion chamber itself. It’s relatively short diameter combined with the wide paddle means that agitation is very easy to repeat. There’s not a lot of room for different stirring techniques, so basically you are able to count the number of times you back and forth and repeat it time and time again. Even though it may seem a bit wobbly, extending the chamber fully and inverting the Aeropress gives you a solid handle on creating an isolated, easy to maintain brew chamber.

And yet, there’s something still to say about using pressure as an agent of agitation. Espresso, siphon, and now Aeropress — there’s a certain liveliness to all three of these brew methods. Who knows what sort of scientific evidence backs it up — all I’m saying is that the coffee I’ve been brewing is frakkin’ delicious.

Since this is not yet a How To piece, but rather an essay, I’m wary to include the brew recipe I’ve been using. At the same time, however, there are so many complicated ones out there that I think the simplicity of this method I’ve been using deserves to be examined.

Inverted chamber with plunger halfway through the circle 4. Fifteen grams of coffee ground at a V60 setting. Water around 200 degrees Fahrenheit: 185 grams of it. Agitate at 45 seconds with Aeropress paddle until bloom collapses into itself, about four to five stirs. Attach filter. Flip at 1:30, slowly plunge with weight of your hand (not force). Finish plunging at 2 minutes just before you hear the hiss. Finish pressing out all excess whatevers into a sink, let sit for five to ten minutes, and the puck will have dried out and will pop out easily.

It’s easy. It’s fast. It’s clean.

There is something I do have to admit. My biggest love for the Aeropress comes in it’s size. I’ve yet to run into a brew device that singly brews six ounces or less competently, and when you work everyday leveling espresso, I don’t always need the 14oz or so that my V60 relies on jazzing me up before I get to work (you can brew less, but I’ve found it harder to repeatedly brew solid extractions at lower volumes on the V60). Having soft skin means I’m constantly brewing coffee on my fingers and absorbing it through my hands.

I do need to end this with one caveat: every brew I’ve been loving with my Aeropress has been with Coava Coffee’s Disk filter. Originally punched out of leftover sheets from their Kone filter designed for the Chemex, the Disk is an etched piece of metal that resembles the bottom of an espresso basket, if only espresso baskets were that precise in their hole arrays.

Now, this may be because I’ve been loving the profile it offers, or it may be because I forgot to steal paper filters when I stole my dad’s Aeropress. Or maybe I subconsciously didn’t even think to take them, since my sole idea was to steal the Aeropress to test out the Disk. In any case, with a proper grinder, the coffee tends to dam up behind the filter like in an espresso basket, meaning that very little fines/sediment make it through the filter, while a shitload of deliciousness does.

I’m going to say it here, right now, and mean it — the Disk outperforms the Kone, hands down. As great as the Kone is, it’s design leaves room for interpretation. In pour over, the paper filter acts as a regulator for flow. With the Kone, brew times can vary, and need to be monitored. The Disk, however, has no real issues competing with flow on the Aeropress. It’s pushback feels very much the same as paper, and gives you a good sense of pressure profiling (wink).

But what I love more about The Kone, The Disk, and the upcoming Funnel (wait, what?) is that there are now brew methods (or paraphernalia) that are being concocted by real, honest to God coffee folks who know what they’re doing. No longer is it a crapshoot invention re-interpreted by a coffee public. We’ve got someone batting for the home team, finally.

What was the point of this whole debacle again? Proving that there’s salvation in technique? A re-examination of brewing culture and high-tech modders? Or was this just a big thank you to Keith and the Coava crew? I’m not so sure. I feel like an old man trying to deliver a speech while the point is slipping away…

So this may not end poignantly. But I’m going to try and wrap it up simply: I really enjoy brewing on my Aeropress, and I really enjoy using my Disk. I’m not sure what this means in our eventual progress towards the singularity, but I know that there is redemption for brewing devices, regardless of the evil intent of their creators.

Thoughts: Communicating the Life of Coffee

At the same time, this is totally awesome. If you haven’t already clicked the link, I’ll tell you what it is. It’s an interactive poster that explains every step of how the coffee Intelligentsia buys is cultivated and then roasted. You really have to go check it out yourself.

The best part is, however, is that this isn’t just a website. The top brass have printed up thousands of copies of this on a large newsprint fold up, and placed them in the store. While it seems a bit like war-time propaganda fliers, I think it’s the best way so far I’ve seen for educating customers.

Any time someone is waiting for a drink, they have the chance to pick one up, and find out new information about coffee processing. And while Intelligentsia has some flashy retail operations, the most innovative work that happens is on the back end.

Like how the company imports it’s own coffee. While this doesn’t seem like a big deal, Intelligentsia is the only roaster of its size that’s currently importing its own coffee. This means that Intelligentsia is getting their coffees in months before anyone else is. Intelligentsia was also the only roaster who was able to be present at Ethiopia’s new Direct Specialty Trade auction, due to the company’s status as an importer.

That’s a pretty important factoid that isn’t easily slipped into conversation. Kudos to the fellas at the Roasting Works that put this together. It truly has me in awe.

Direct Trade Interactive Map

Reviews: Coava’s Kone Filter

I’ve been listening lately to the Planet Money podcast, in which they have been talking a little about American manufacturing. After visiting a button maker and a place that manufactures connectors (those little gold pieces of whatever that connect different components on circuit boards), the Planet Money team found that American manufacturing mainly succeeds in the case where innovation and intellectual design come into play. This means — the button company? Out-bid by Chinese button factories. The connector factory? Dedicated to fabricating and producing new connector technology developed by their R&D side, and successful.

We’re getting somewhere with this, I promise.

What the podcast didn’t cover, however, was niche-market manufacturing. Small-scale production just doesn’t register with national economic indicators, so overlooked it went. And if there’s one industry that loves small scale niche-market manufacturing, it’s the goddamned world of high end coffee.

Whether or not you want to include hand-built espresso machines in the category of manufacturing, we’ve got companies every day trying to find a new product, or way of looking at a product, and turning that into a fabricated reality. Examples? Pour-over stands and drip trays, tampers, pour-kettle flow-restrictors, etc. While most of these companies are dedicated to improving existing technologies, the ones that reinterpret the game are the ones that everyone is excited about.

I’m talking, right now, about Coava’s K-one (Kone) stainless steel, conical filter for Chemex (and sort of V60 as well).



Now some people might say that this is just a reinterpretation of the Swiss Gold basket that drip makers have. I say phooey. Those baskets are a fine metal mesh. The Kone is something different altogether. It’s a single sheet of stainless steel that’s been wrapped into a cone shape, and has a strange array of holes punched through it at different intervals.

Marrow has a good rundown of the design, but here are some important excerpts to know:

The design is entirely custom, and the CAD drawings were drafted by a local engineer and submitted to a manufacturer on the East Coast. The stainless steel is sourced from Ohio and the filter’s holes are created by photochemical etching. The process creates a taper in the holes; the holes are bigger on the outside and smaller on the inside.

They also talk about how the Kone tapers quicker than the sides of the Chemex, so coffee can exit the filter whenever it deems necessary. This is a point of contention in pour-over brewing. Some people like the fact that water has to travel to the zenith on a Chemex filter to exit. Some people like the fact that water can exit easier through the sides of the V60.

I like the fact that pour-over style brewing can deliver a delicious cup of coffee.

Before we start discussing the potential environmental impact this has on coffee brewing, let’s talk about the results.

I’ve used the Kone with my standard Chemex and V60 brewing specs, and what it delivered made me rethink the way coffee can be brewed. I’m not just blowing smoke up your ass. It’s true.

The first Chemex brew I had with it had me swearing aloud to an empty living room —Fuck that’s good! — and if you’ve ever had the urge to yell obscenities to yourself and the reproduction mid-century modern furniture your wife picked out, then you might understand how good this coffee was (or maybe you’re just going crazy [and maybe this metaphor is too abstract]).

The profile was reminiscent of a Cafe Solo — a very “natural” cup that rings true of the flavors experienced in a cupping, but at the same time it was different. While the body and fullness of the coffee’s essence was there more than I expected, there was a singingly present acidity and brightness that I usually attribute to the Chemex’s thick oxidized filters.

Which means that — holy shitballs — maybe it’s not only the filter that helps highlight a coffee’s acidity when brewing a Chemex. Maybe there’s something else to it.

Like the hybrid of a device that it is, a hybrid cup profile it presented, and replicable it was. Chemex number two was the same business.

V60? Now that’s when this gets interesting. It was very reminiscent of, well, a V60 brew. I haven’t had the chance to play around with it as much on the V60 as I’d like to, but whatever, right? It works, it was delicious, but it wasn’t mind-bendingly different. Will have to explore that in the future.

One last note and then we can talk about sustainability, all right?

All right.

What blew me away more than anything, I think, was the way in which the filter mimicked the flow rate of paper brewing. While the flow is technically a bit faster than with a standard paper brew, the way that the pour reacted was very paper like. This is due to the hole pattern etched out instead of just a mesh filter design.

In all honesty, it reminds me of a portafilter basket. You want enough holes to allow for flow, not too many to restrict flow for a better brew time. And in the bottom of the brew? A limited amount of sediment. It’s true — the least amount of sediment I’ve seen in an metal filter style brew.

Okay, now for all you hippies out there, sustainability.

Coffee filters are bio-degradable. You can compost them right in there with the coffee. But disposal isn’t the aspect of coffee filters that’s the problem. The problem is paper. Paper which comes from trees. Trees which have to be farmed. It takes a while for a tree to mature, as well, to be able to harvested and turned into lumber/paper. While we’ve made some steps in the logging industry to replenish our forests (and swamp loggers — I salute you!), the Kone will definitely help you sleep well at night.

It’s reusable! Over and over again you can brew with it!

Except…

It’s a stainless, reusable filter. Which means clean it. No, I’m serious. One of the great advantages of paper filters is that they offer a quick clean up, and keep your equipment from getting gummed up with oils. I hadn’t thought of this, so on my third Chemex brew with the Kone, whammo: bad french press tastes.

I hadn’t experienced that in years. I’ve long since given up dirty, gross french presses for the easier to clean and less-agitated Cafe Solo. The taste of rancid coffee oil locked in a filter screen is a thing of the past. But I experienced it again with the half-cleaned Kone.

And your Chemex, too. With a paper filter, most oils don’t make it to the bottom of the Chemex. Now they do. Hot water rinses aren’t going to do the trick. Invest in some Urnex/Cafiza/Full Circle or whatevs to keep your equipment clean.

Also? Found out that the Kone is dishwasherable. I probably wouldn’t recommend throwing it in the dishwasher, but if you aren’t paying attention when loading your dishwasher, then yeah, it won’t fall apart.

To be honest, I haven’t properly given the Kone the full treatment to be able to say that yes, without a doubt, 100% this is the best idea since we decided to abandon the percolator.

But I will say is that I decided to write this review because of the absolute potential that the Kone possesses. Who cares if this thing is your favorite new brew device? What truly matters is that it’s worthy to be thrown into the arena.

What arena is that, you ask?

Why, the coffee argument arena, of course! Every brew device that we use (and especially recently invented ones [see: Clever, Aeropress]) is subject to months or even years of hot words, slander, undulating praise, and sheer vitriol.

The truth is, we have no clue what we’re doing. Oh, we have an idea, sure. But I’ve examined brew concepts for years thinking one thing, only to hear a dissenting opinion and change my mind completely. Now I’d like to think that I have a clear idea about what’s going on with my coffee brewing. I mean, I do it professionally, day in and day out. So when I say “Kone, yes!” I mean it.

Will someone prove me wrong? Doubtful. It’s great. I love it. I think you will too. But someone will probably try to prove me wrong. And that’s what I’m most excited for. Dissenting opinions about brew methods breed innovation. And innovation is what drives the coffee industry forward.

Innovation, perhaps, like designing and manufacturing a stainless steel, reusable filter for Chemex, with which I brewed the best tasting cup of coffee I’ve had at home in about five or six months.

Linkage: Latte Art Article Up on Fresh Cup

Short post going here to link you nice folks to an article I wrote about latte art for Fresh Cup Magazine.

In it, I talk about whether or not the bitterness of crema is highlighted by latte art, and how we should approach latte art responsibly, using basis from James Hoffman’s videos, and a short interview with Mike Philips.

You can see the entire current issue of Fresh Cup here, with my article starting on page 48.

Bonus: They chose the goofiest looking picture I sent them for the main image of the article. Also, the one day I had a pro photographer to work with, my latte art was off. Mediocre pours in a national publication for the win!

Reviews: Mypressi Twist

When I first shifted Bitter Press over to the coffee blog it deserved to be instead of a loose mish-mash of whatever, I had one simple directive: accessible brewing methods that can both improve the coffee that professionals are making themselves at home, and can help introduce new home brewers to fantastic coffee.

I can’t think of a single espresso device that does the job better than the Mypressi Twist. And I mean device. Through most of espresso’s lifespan, it has always come down to a machine. An espresso machine. A hulking mass of steel, boilers, and phallic portafilter protrusions.

A machine this isn’t. The Mypressi Twist is a handheld, trigger activated, goddamn space age ray gun of espresso. In every way, its spherical bulb and twisted handle resembles the utopian future promised by 60s sci-fi writers: a glass dome for every roof, a jetpack on every back, and a portable espresso device in every hand. And why not? For all the talk about semi-commercialness of parts integrated into the low cost of the Rancilio Silvia, why not talk about the semi-commercialness of parts integrated into the Twist for a mere fraction of the cost?

Like most espresso experiences, test-driving a Mypressi Twist is really just an exercise in testing the accuracy of your grinder. I found my experience to be frustrating to a certain extent. When the shots pulled the way I wanted to, they were great, but dialing in an excellent pull took longer than I wanted it too, and when you have to disassemble the entire device and boil new water every shot, it becomes a bit of a chore. But more on that later with some hard data to back it up. Let’s examine the philosophy behind the Mypressi Twist.

By slowing down the espresso process The Mypressi Twist gives you a bit more control over the whole process than you would get in your average espresso experience. Great baristas are taught to dose by basket volume and intermittently weighing the dose to make sure that he or she is on point. With a Mypressi Twist, there’s no reason not to pre-weigh your dose before you grind.

With no boiler system, you have complete control over the temperature of the water that you’re adding to the reservoir. Heat retention seems to be an issue discussed, but without using a thermometer, I found water right off the boil to be adequate for brew temperature. Espresso came out at a drinkable temperature, but still very hot. In my estimations, starting water was around 199-200 degrees Fahrenheit. The important thing, though, is that there’s no temperature swing to account for. The cheaper pro-sumer models of espresso machine tend to have a 10-20 degree temperature swing, and that’s no good for espresso, where every variable matters.
Inadvertently, this portable espresso device gives you similar control that a professional barista has with a PID controlled boiler system. Control over brewing variables is the most important issue with coffee preparation. It’s putting means of production into the hands of the masses. We truly have the first socialist espresso device on our hands.

All you need is is to the pair the $150 or so Mypressi Twist and a $250 or so Baratza Virtuoso grinder, and you have a sub-$500 espresso option for home or work. Or heck, get fancy, and put Mypressi on your coffee bar’s coffee menu. The cheapest consumer/commercial hybrid machines you can buy that are worth working with will start you at $600 on their own. It’s expensive, sure, but it’s also accessible in a way that’s hard to describe. Or maybe it’s not.

Half the power of the Mypressi Twist is the strange phenomenon that surrounds it — the power of lowered expectations. Upon first sight, upon first demonstration, there’s no doubt that the Mypressi Twist will raise, well, doubts. It doesn’t seem possible that this fidgety device can prepare solid espresso options. Going into home espresso preparation with low expectations is key. There’s a reason that high-end espresso machines can run up to $20k. And a reason that the Mypressi Twist costs $150-170. The ability to drive professional baristas into full blown shock and awe is the trick that the Mypressi Twist has up it’s sleeves.

The low expectations for a handheld espresso device, and the high delivery and low cost of the Mypressi Twist make it a befuddling brew device, for sure.

With that in mind, let’s take a look at a table full of my collected data. In the week and a half of having the Mypressi Twist at my disposal, I pulled way more shots than documented, but this represents two days worth of data gathering. Previous attempts found that 18 grams of coffee was generally the target weight I wanted to use for evaluation. My first two pulls were at a straight 2 grind setting on the Virtuoso and pulled beautifully and delicious.

Then when time came to repeat the experience, things went a bit awry.

More than anything, this becomes a big ad for the Virtuoso Precisio grinder — one with a micro-adjustment — over it’s predecessor, the Virutoso Plain and Tall.

Other Observations

—Overall build quality is far superior to the original model, which I played with a lot when they first arrived. Plastic is thicker, locking mechanisms tighter, metal heavier. Much better suited to wear and tear.

— The big improvement here is the improved basket design. There’s a slight ridge to it, which is supposed to help pressurize the basket with less than perfect grinds. No way for me to really test it, but I’m assuming it helps.

— There’s now a built-in “shot timer.” Basically, the reservoir top has four different notches, each with a pip numbering *, **, ***, ****. It’s just a little thing, but it’s nice not having to memorize how many shots you’ve pulled with a particular cartridge.

— O-rings. They make the device work, but I had a loose one that I had to swap out for a replacement one. If they don’t fit perfectly, it makes a bit mess. Or just leakes pressurized gas.

— Channeling, and basket size: can be an issue. The basket is narrow and deep, making leveling your dose a bit more of a chore than with a standard 57-58mm basket. This can lead to channeling. Also, not holding the device level can lead to channeling. Making sure you level your dose and hold your Mypressi level will keep the water traveling centered.

Final Take

Does the Mypressi Twist have problems? Yes. But, at the same time, it’s the first espresso device I’m going to recommend to anyone to buy. Hell, I’d recommend it over most entry-level espresso machines, and even some mid-grade hybrids. The potential it holds is great, and the usability and build have never been better.

Personally, having espresso as an option at home creates problems for me. I play around with espresso enough at work, and devoting a half hour to dialing in a great shot doesn’t do my marriage very much good. So sadly, when I return my review model Mypressi, I won’t be rushing out to get one.

As soon as I’m out of a retail situation, however, you bet your ass it’s the first thing I’ll save up to buy.