Archive for July, 2010

Extract Mojo, and Refractometer

Posted in Uncategorized on July 25, 2010 by whyyoushouldhatecoffee

This is our understanding of the Extract Mojo and Refractometer, and how we’ve been using it for the results we have.

Posting this is mostly a hope to start conversation about how to best use the mojo, point out the flaws in our system, and hopefully point out some things we’ve noticed that may help, though in our short experience that’s not likely.


Brew coffee.

Stir Coffee with syringe or eye dropper (supplied with Mojo)

Take 15mL sample and place into clean/dry cupping glass (glass 1)

Stir by moving glass (dissipate heat faster)

Wait 2 minutes then place 3mL +/- into Refractometer.

Press read in Native mode.

Copy Temp. and Refractive Index possibly look at TDS

Place into Mojo, and copy results into moleskin.

Rinse syringe with distilled water (glass 2)

Dump out cup 1 and wipe dry with microfiber towel.

Rinse Refractometer with distilled water.

Wipe Refractometer lens with super microfiber from eye glasses store. (spec optical)

Repeat. allowing time for the meter to cool, notes to be taken and coffee to be prepped/conversation to be had about next experiment.


Guatemala COE

Posted in Coffee of Course on July 15, 2010 by whyyoushouldhatecoffee

I’ve been foolish for the past 5 years.

I’ve been foolish in the sense that I have worked in coffee, and have not taken advantage of an extremely powerful tool that Minneapolis, and St. Paul have to offer coffee professionals, that Tool is Cafe Imports, and Jamin Haddox.

For those who don’t know, Cafe Imports is a green coffee importer, and wholesaler.  Their warehouse is equipped with an awesome cupping lab (no surprise there) and a really awesome coffee lab, equipped with a 2-group Synesso Cyncra, Robur, Anfim (temporary), Probat, Clover, Ditting, Fluke, and Extract Mojo among many other really cool little toys and tools.

Jamin is the Director of Quality Control for Cafe Imports, basically sample roasting and cupping everything that comes through the doors.  He’s awesome and has been super insightful to us and to the coffee industry in the Twin Cities.  Much thanks Jamin!

Jamin has also set up public cuppings of most of the Cup Of Excellence selections of which I haven’t had much of a chance to participate in (bad priorities on my part).  I recently was able to participate in the Guatemala COE cupping, and let me tell you, it was really cool!

The cupping was composed of two rounds of two tables of 7 coffees, 28 coffees total.

I was in attendance along with @MWalcher (Michael), @CoffeeBrigade(Shawn, my roommate), @madcapcoffee(Ryan Knapp),  and manager of @quixotic_coffee(Gordon), all from Madcap’s new account Quixotic coffee in the Highland Park neighborhood of St. Paul. also, @kopplins(Andrew Kopplin) @BullRunDan(Dan, my coworker) and of course Jamin.

COE Farm List

The cupping score in the box is mine (obvious) the one circled is the average of the room, the one above it is Jamin’s (most respected palate/Q cupper) the one way over on the left is the score from the judges at origin.

I was amazed at how consistent our room was considering that this was my first COE cupping and our group doesn’t typically cup 28 coffees at a time.

Mojo vs. V60 01

Posted in Coffee of Course on July 15, 2010 by whyyoushouldhatecoffee

The Hario V60 has been a source of debate for me.

The brew method, is currently quite widely used and has been adopted by many as “The Standard”  To me this is intriguing for two reasons:

To create good coffee, requires extreme consistency and extreme skill and knowledge. (like Espresso)

To create good coffee, it seems as though you actually have to work against the system.  It brews really fast!  You practically need a Hario Buono, or similar kettle, to pour/drip slow enough otherwise you end up with an under-extracted tea like coffee beverage.  There’s always upping the dose to accommodate, but really?

I wanted to give it a run through using a few different techniques to get a further (hopefully) grasp on how it works, and what factors matter the most i.e. time, dose, grind or turbulence among the many many others.  For this experiment we used a coffee that we are pretty well familiar with: San Pedro La Laguna, Guatemala.

As it seems fit, we started with the technique that Justin has been working on.  Justin’s main theory is that people don’t rinse the filter properly and that the little air bubbles between the filter and the wall of the V60 cause channeling later on.  I believe it to simply be speculation and that the coffee and water’s mass compress the pockets. unfortunately there is no real way of knowing.  But that’s what we started with.  Super Flush.  pre-infuse with around 30mL for :30 seconds. then slow pulses to keep the bloom for :30 seconds, then a slow pour matching the speed of the water coming from the bottom, while keeping the slurry about half full.


As always we tried to keep everything as consistent as possible, in only isolating one variable at a time.  This seemed to work.. kind of.  In this case, that would be the grind setting.  It worked out alright.  We have issues with the brew time changing, more specifically the drop or the finish, after the pouring is done.

We can speculate that this is because of a few things:

Justin “releasing fines that have clumped to larger particles, clogging the filter.” this is from turbulence.

Too much or too little Turbulence. inconsistency.

The little circle that you pour. maybe that changed.

In the end we decided that this may be more difficult than it is important in the Cafe.

Round 2:

The long respected Barismo Spec. (Or at least our interpretation of. I don’t want to offend anyone by our mistakes or misuse.)

Divet,  30mL pre-infuse for :20seconds, 180 mL over 80 seconds on a backwards timer.


In the end, we concluded that this would not work very well in our cafe, as we serve 8oz. and 12oz. this is simply too little coffee, and changing portions doesn’t really work in coffee. sad face.

Round 3:

Of course @NickCho has some twist on the Hario V60 and how he uses it! Thanks Nick!

So, once again, I don’t want to offend Nick, or anyone else who uses this method.  This experiment was to find what would be the most fool proof, consistent method that we could for the Cafe.


In the end we decided that to try to train a staff to consistently pour 8-15mL bursts every 5-7 seconds would be a bit more complicated than showing them what thickness of stream they should be aiming for.  Interesting.

We also, throughout the experiments found that Time is not as significant of a variable as we have all been thinking!  “Time Doesn’t Matter!”

We found that we had pleasant cups at 2:30 and at 4:15 finish.

Turbulence is Huge!!!! or that’s our theory.

Extract Mojo: Take 2

Posted in Coffee of Course on July 14, 2010 by whyyoushouldhatecoffee

The second round:

This attempt, was me (Keith) continuing to be anxious about the Extract Mojo Refractometer, and the readings we had gotten from the device paired with the Clover.

I was anxious, because:

The device is really expensive and therefore should work
The industry has called the device revolutionary
It makes sense.

So then why is it not consistent and why is the coffee super under-extracted.

This time I brought:

Coffee from Intelligentsia. The Edelweiss Finagro Estate: Tanzania. It was fresh, a different coffee, and I had 2 lbs. of it.

A microfiber towel. for wiping the screen of the meter.

Cupping glasses for transferring coffee.

We, Jamin & I also used a Fluke thermoprobe (supernice) to measure the temperature of the slurry during a longer clover brew cycle.

Our approach changed. We don’t want to use the Clover like we have been using the Clover. It yields underdeveloped confusingly extracted super up-dosed really bizarre coffees..
We just want awesome coffee.
We tried some things.

Using the Ditting 7 grind setting, the first attempt was 24g coffee 8oz. water a mild stir “pat” and 60 seconds(longer brew time coarser grind).

Results varied between 1.08 and 1.20 on the meter.
1.3340 and 1.3344 That’s huge for the same coffee.
.59 TDS on the Mojo ToGo not even on the charts for EXT %

Second attempt:
Using Ditting 4 (finer than our cafe setting of 5), 24g 8oz. mild stir “pat” and 60 seconds.
isolating the grind setting as the variable (in theory).
1.3353 @ 27.6 degrees C
Cool! 14.45 EXT % and 1.74 TDS
Really bad coffee, but extracted!!

Ditting 4, 24g, 8oz. 90 seconds. isolating time as variable (in theory).
1.3353 @ 26.7 degrees C
1.67 TDS 13.5 EXT %
I’m just really excited we’re getting readings.
Bad ones, but readings none the less.

Other experiment: Slurry Temp. over Time.

180 second brew time 360mL
at 120seconds – 187 degrees F
at 90seconds – 182 degrees F
at 60seconds – 179 degrees F
Finish – 165 degrees F

Maybe long brew times do not = Awesome.

Extract Mojo & Mojo ToGo

Posted in Coffee of Course on July 14, 2010 by whyyoushouldhatecoffee

Recently we got to experience something that I have been extremely anxious to try out and use, though have been limited due to my lack of sufficient income to purchase said Extract Mojo.

Fortunately Jamin, at Cafe Imports has one!

Justin & I have been making as frequent trips as we possibly can to get a further grasp on A. how it works & B. how coffee extracts and reads out on the meter.

For those who don’t know what I’m speaking of, my understanding of the Extract Mojo Refractometer is that it measures the refraction index (how much light is sent back to an emitted light) of a said liquid. In our case that liquid is Coffee, and the refraction index helps us to compute (with Mojo ToGo, iPhone App) the TDS (Total Dissolved Solids) and the Extraction Yield %.

The TDS we find helpful to determine the strength of the coffee, and the EXT % we find useful to determine how much (%) of the chemical compounds and solids have been extracted from the measured quantity of coffee that we used.

During our first experiments, Justin & Eric Kamosa were attempting to dial in some of our new coffees on the Clover brewing machine, while I was attempting to take meticulous notes, and compute readings from the meter, through my freshly purchased Mojo ToGo.

Our Findings, to be honest were inconsistent.

We attempted to cover as many bases as we could, I guess we hadn’t really realized that the Mojo is so freaking intense!

through our trials, we attempted to keep things as consistent as possible covering:

Turbulence: Barista to Barista this changes, but a Barista can try to be consistent as long as that’s their aim and it’s small amounts.
Typically just small “pats” to wet the grounds.
Though Justin typically waits for the water to st
art spraying and then throws in the grounds, using the spray head as a creator of turbulence, and not allowing the grounds to sit on a hot screen (baking)(speculation).

Filter: We tried filtering the coffee beverage with the syringes, and rinsing them in between uses, with the theory of removing as much of the solids from the filter as possible (using cold water from the same source as the brew).

Temperature: for the brew, it seems rather difficult to do anything to make this more or less controllable, being in an exposed cylinder, but we always rinsed seconds prior to the actual brew cycle (heating the piston up, in theory). The temperature of the beverage we used for reading in the Refractometer is where we really messed up. I guess I was just super anxious, but we didn’t use a transfer cup, and therefore didn’t really allow it to cool, so all of our attempted readings were from a liquid around 30 C. That’s way too hot for the meter to get consistent results.

Cleanliness/Purging: Like I said we rinsed and wiped the clover between every brew cycle. We also rinsed and purged the syringe between every cycle attempting to remove the brown from the filter. We wiped the screen of the meter with the little alcohol wipes that were supplied with the meter (didn’t seem to work well.)

The results for the day entailed a range of readings from the meter between 1.3330 and 1.4092 and a TDS of between .82 and 1.67 which is probably all a relative guess, considering our unfamiliarity with the device. We tried around 15 different readings, and in the end just dialed in how we had been…

To Taste.

It has encouraged us however to find a more consistent solution to: cooling the coffee
wiping the screen of the meter
getting at least close to the little boxes in the app.
measure the coffee mass more accurately .01g
measure the coffee liquid more accurately gram scale. (mass)
hate Clover coffee

Introduction to my ideas

Posted in Coffee of Course on July 14, 2010 by whyyoushouldhatecoffee

First Post:

Today, I (Keith Mrotek) embarked on a Journey.

I’ve been on a Journey, for quite some time. The missions of this Journey, I’m going to attempt to chronicle in this blog.

The premise of my Journey is to “understand” Coffee.
It’s a beverage and a business that I have developed a love hate relationship with.

My goals are to:
A. Find out what I love about it.
1. In regards to the Industry
2. In regards to the Community
3. In regards to the Green & Roasted Product
4. In regards to the Ground & Extracted product
5. In regards to the Final Product

B. Find out what I hate about it.
1. What keeps me working in it (spitefully)
2. What keeps me Motivated (angrily)
3. Why I hate the “system”
4. What I hate about making it
5. What phases I hate going through

C. Help myself to at least enjoy the Journey.

I should assure you that this will not be a blog about actually hating Coffee. I really love Coffee. That should seem pretty obvious as I’m starting a blog about it. Hopefully I can shed some light on some issues I have, and moreover, I can all come to have a better understanding and love of Coffee.

I should also assure you that I do not consider myselve “the best” or an “expert” in the industry, but simply a student of the craft. My goal is to quite simply understand Coffee in as many respects as possible, and shed light on as many topics, as in-depth as possible, while trying to be as objective about results as possible.