Mojo To Go

Since Mike White called me out on this I thought I’d post quickly about my experience so far with the ExtractMojo iPhone app “MojoToGo“.

I bought the apps as soon as I saw David’s post about them – I had known something was coming for a little while, but had just been a bit smothered in work stuff.

So far I have to say it’s great.  What has been most useful has been the ability to save and email recipes with notes about the coffee – something that I really need right now!  I’ve been working on syphons quite a lot recently, trying to find the simplest route to tastiness.  The geek in me loves complex technique, but a bigger part of me likes elegent, simple solutions – not just from an aesthetic point of view but also for repeatability.

I’ve been trying to do some cupping bowl experiments, but I’ve found this much trickier – there is continued extraction after the break, so the question is (in my head): when do we want a cupping bowl to hit its peak of extraction?  Just after the break? At 10 minutes? At 20?  I’ve pretty much discounted my previous cupping bowl tests, as my methodology was stupid – but I plan to repeat the experiment after SCAA – will post anything interesting I get from the results. Along with a big post about cupping in general that I keep meaning to write.

I’ve gotten off topic a bit – the iPhone app is great, the new bundle means the entry price point has come down and metering both espresso and brewed coffee is cheaper too.  This is a good thing – my only complaint: you can’t buy apps for other people.  It would be nice if you could buy the app for staff – but this is Apple’s fault, not Vince’s!


25 Comments Mojo To Go

  1. Glenn

    My head has been pulled in many directions over the past week since downloading the Apps and also upgrading to v2.0 of the Extract Mojo software for PC.

    Taste and Science do not always correlate (as I found out with syphon brewing experiments a few nights back) and this has been puzzling me. I guess it depends on the roast, the grind and the baseline characteristics.

    Should some cofee taste better when the science says it is underextracted?

    What looks and tastes acceptable may fall outside of accepted taste parameters for the SCAA, SCAE or NCA.
    Hopefully the new research (referred to in Paul Stacks blog) will shed new light on this.

    Your thoughts would also be appreciated

  2. Galyon

    Great question Glenn, i too am interested in hearing Jim’s thoughts on that.

    Jim, after your cupping post you should do a post (or vid) on the most tasty syphon method you came up with :)

  3. James Hoffmann

    I find that when readings drift away from where I’d expect them (by taste) then a quick recalibration of the unit is worthwhile. Often the temperature of the glass has changed, and the re calibrated readings are more inline with expectation.
    That said – I struggle with many cups over 20%, prefering 18-20% as a personal range.

  4. Lawrence Brown

    Your only complaint has been solved, you will be able to buy applications as gifts in the new iPhone 4.0 OS – this will be arriving to handsets over the next few months!

  5. Mike White

    I’m a fan of the app and I don’t even have a refractometer (yet). The accessibility of the software (or lack thereof) was a problem for me since I don’t use a PC. Now I can MoJo under the table when visiting cafes, Kaminsky style (

  6. James Hoffmann

    The challenge with guerilla refractometery (if that isn’t a thing then it should be) is you need the coffee to water ratio to get useful data. Maybe if you know a shop’s press pot or pourover standard you can get close but with espresso you stand no chance.

  7. Nick Cho

    I’m a BIG fan of the Mojo. There’s a LOT to glean from the data.

    That said, the % extraction yield needs to be put into perspective. It is good for calculating the optimal extraction yield from the brew you refractometered, and it’s immediately relevant to a great many brews.

    But the actual brew is sometimes less-than-optimal. If there is uneven brewing (i.e., the way that many do their Hario V60 brews necessitates a quantity of almost-dry grounds at the top edges of the bed), the extraction-yield figure is less relevant. It’s STILL a bit relevant, and will help illuminate your overall brewing parameters, but it’s tricky.

    I don’t think that I’m stating this very well, but anyway. :-)

  8. Paul Stack

    I’m unashamedly a big fan of the coffee refractometer/Extract Mojo combo. I’ve been using both for about 9 months now and once temperature stability and frequent calibrations are part of your modus operandi, brews can be diagnosed, tweaked and great results achieved. The Mojotogo makes it fast, portable and ‘shareable’. The BrewHaha this week was a great outing for the App and a great teaching tool for the uninitiated.

  9. malachi

    Spot on Nick.
    It’s a great tool – but it’s not the Truth.
    As with any simple answer to a complicated problem – it only tells part of the story.

  10. James Hoffmann

    I don’t think anyone is claiming it to be the Truth.

    A probe in a roaster gives you a reading of the bean mass. It is not absolutely correct, but it provides useful information to guide the roaster. It helps achieve repeatability and understand degrees of change/movement.

    As I said above – I’ve not had a lot of brews that charted out above 20% that I’ve really enjoyed, despite them falling into the “correct” category. Taste still wins out, but I had a good cup become great when I nudged it from 17% to 18.5% and I am grateful for the accuracy and incentive.

  11. AndyS

    > If there is uneven brewing (i.e., the way that many do their Hario
    > V60 brews necessitates a quantity of almost-dry grounds at the
    > top edges of the bed), the extraction-yield figure is less relevant.

    Nick. I don’t waste time using Mojo to analyze faulty coffee brews, just as I don’t bother to analyze spritzing, channeled espresso shots. One doesn’t need numbers to know that those kinds of extractions aren’t right.

    If, as a side benefit to the increasing use of Mojo, people move away from techniques that produce uneven extractions, their coffee will most likely improve.

    But it won’t come easily. Scott Rao argued presciently for this (in the “Why you should hate the Chemex” thread on; he was met with a torrent of stubborn, emotional criticism. OK, OK, OK, he readily admits that his choice of thread title was controversial. ;-)

    > It’s a great tool – but it’s not the Truth.

    Obviously, Chris, an “underextracted” 17% extraction of a great coffee is going to taste better than a “perfect” 20% extraction of a crap coffee. OF COURSE the numbers aren’t the whole story, and of course they aren’t “Truth.”

    If people wouldn’t be so threatened by Mojo… if they didn’t keep coming up with speculative theoretical objections to it…if they just gave it a sustained, fair trial…they might be shocked how useful it is.

  12. Aaron Ultimo

    The Mojo To Go has made my refractometer so much more relevant. Mojo for PC was good, but inaccessible for me most times. Now I can do quick tests at the shop and get the data imputed instantly. I’m excited at what I’m learning so far, but have also experienced the phenomenon of liking things that fall outside of “optimal” or not being totally sure if I’m enjoying what is considered spot on. That’s where I remind myself that the chart is based on a collective preference and my tastes may just differ a little from what is charted as perfectly extracted. Or that my mouth is just broken. In any case, I’m thrilled by this new app and have already learned a ton about brewing.

  13. Pingback: Coffea® Prima – single cup coffee brewer

  14. Daniel M.

    Newbie alert…

    So, am I to understand that one connects their refractometer to the iPhone? Or is it merely that you take readings from the refractometer?

    I’m but a home-brewer but I am geeky enough that this looks like a fun toy. Anything that gives me data and is going to help with consistency, well, I’m all for it. Any advice for someone who has never touched the Mojo?

  15. AndyS

    You take readings off the refractometer and manually enter them (along with dose and beverage weight measurements) into the iPhone .
    As far as advice goes, I would get the app and buy or borrow a refractometer. Then play with them! The utility of these techniques for brewed coffee has been established for decades, but for espresso this is pretty new. There is plenty of room for experimentation.

  16. AndyS

    Brewed coffee is very dilute (from a refractometer point of view). To make fine distinctions in such a dilute solution requires a very sensitive instrument. The refractometers on the mojo website are sensitive enough to do the job and are calibrated accurately for coffee.
    Unfortunately they aren’t cheap. I think Vince Fedele has said that only a few years ago, such accuracy would have cost $1000-$2000.

  17. J

    Please keep in mind that the brew chart’s acceptable range of extraction, 18-22%, was crafted based on a series of PREFERENCE taste tests on a panel of consumers. Though it was a statistical extrapolation from the survey, the general palate of the nation can and do shift over time. For example, Americans prefer much more saltier or sweeter foods than they did decades ago. Do you really think Coke Classic is exactly the same recipe or target taste profile as it was 50 years ago? Or how about the fact that many older folks still prefer the taste of Foldger’s?

    Can you have a superb shot of espresso that is outside of the 18-22% range? I argue YES, depending on the coffee being used, taste preferences, and subjectivity. This 18-22% goal is akin to other established, traditional espresso preparation parameters – temperature & pressure – which arguably are now very subject to change with the availability of pressure and temperature profiling equipment. Or take the 60g/L brew ratio rule, for example. I’ve had many coffees brewed on pourover bars from many reputable cafes only to be disappointed in getting a less than stellar cup because they based their dosage on the 60g/L rule (resulting in about 18g per cup). I brew mine at 25-38g on a Bonmac and people love it. Using a refractometer, the numbers are off the charts!

    Bottom line, Mojo To Go and ExtractoMojo are calculators based on these presumed “rules”. At best, I view these as suggestive “guidance” tools, rather than absolute indicators of how you should brew. To say that only good coffee is within the 18-22% range is like saying the true indicator of economic health is the Dow Jones index.

  18. Glenn

    No as different refractometers have different tolerances
    However, the Coffee and Espresso refractometers are now interchangeable.
    I use the Coffee one as standard but get accurate Espresso readings too thanks to the MoJoToGo app and having upgraded to the full ExtractMojo version

  19. Benjamin Turiano

    Finding the % extraction isn’t about rules. You can choose to land somewhere between the 18%-22% range, but it isn’t a requirement by any means. The Mojo is much more about understanding your preferences and making them repeatable, even if they are outside of the standard range.

  20. Paul Stack

    The 18-22% box is based on data which is more than 50 years old and came from consumer preference data at that time for coffees tested in the US Market only.
    In 2010, it is remarkable the 18-22% range is still relevant as a target extraction range. It is, but needs re-validation.
    The Mojotogo app and the refractometer shouldn’t be dictatorially aligned with this 18-22% range. It simply brings an ease of use to the everyday roaster/cafe/barista which enables one pinpoint a brew, be it liked or disliked. Once you know where you are, at least you can choose in which direction to go or whether your current locale will do nicely, thank you very much.

  21. Pingback: MoJoMentions- VST

  22. Jgorl804

    from someone who completely dumbfounded by it all…just want to add-thought i remember seeing something about google accepting ideas for apps….something to think about as far as app that can give apps to others…idk if apple does that?? just having a thought “way to early” in day. peace.

Leave A Comment