The need to calibrate

On bars these days you find more and more usage of scales and thermometers but less and less interest in calibration. Like most things, there is a balance between dependence on something and willingness to check that what we depend on is accurate.

Here are a few things to calibrate and a few easy ways to calibrate them.

Scales: Some scales come with a gram weight which can be used for calibration. Alternatively, you can purchase a set of weights for calibration purposes. For your small scale that would be measuring amounts such as gram doses, a nickel is a good calibration tool. A nickel weighs 5g and once you have zeroed and tared your scale, you can simply place a nickel on it to see if it is accurate. A better way of calibrating a scale though is to measure the maximum capacity of the scale. If the scale maxes out at 5lb, finding something like a 5lb bag of sugar to measure the maximum of the scale. RTFM applies in all situations as many models of scales have calibration modes outlined in the manual.

It is also a good idea to make sure the scale you use for measuring small gram dose weights has a small enough resolution to be practical. Some scales have resolutions that vary as much as 5g as they are designed for weighing larger amounts, some are used for precision measurements of small amounts but need to be tared often or reset and tared between measurements.

Thermometers: Thermometers are easy to calibrate and hopefully everyone manual brewing coffee is measuring temperature. To calibrate a thermometer, simply fill a cup with mostly ice and a little bit of water allowing more than 80% of the probe to be submerged. Let the thermometer sit submerged for one minute and then observe the temperature. It should measure at 32f/0C. In conjunction, a measure of water at a rolling boil can give another data point. Placing the same probe into water at a rolling boil should give you a measuring point of 212f/100C unless you are at high elevation to which your boiling point may differ. (To verify espresso temperatures, we recommend getting a Scace and calibrating it the same way in both ice water and boiling to establish group head temperatures.)

Note: The usefulness of calibrating thermometers was most apparent for us. With our installation of two roasters (identical), we found the temperature probes (and spares) had a range of variance within 2 degrees. After identifying the offsets, we then programmed this into the displayed temperatures. When changing the temp probes, we would have to repeat the process of calibration.

Flow Meters: The traditional flow meter in an espresso machine is one of the most difficult items a professional barista can use. In many cases, we tend to abandon this because constant recalibration is needed. The reason being that in the dual boiler machines we use, the volumetric component isn't designed for precision and is placed in a position where hot water sits and scale buildup occurs. This creates many problems that makes it less than useful and often a hinderance. Recalibrating involves either a scale weight of the resulting shot (remember mL and grams are exchangeable) or a volumetric estimate with a 'shot glass.'

In the next year, a new type of flow meter will be introduced in coffee brewing that should not be confused with the volumetric controls on an espresso machine. The LuminaireCoffee volumetric controls are a generation ahead in that they function with more accuracy and are more useful in what they display. As opposed to the volumetric controls on an espresso machine, the LuminaireCoffee flow meter is in the cold water section and has less issues with buildup or hard water. It also is precision and digital which is best exemplified when using it in manual mode as it functions similar to a chronos display of time on a La Marzocco espresso machine. It simply displays total cumulative volume and time counts (and a dynamic flow in either ml/s or oz/min) as you are brewing. (In preset mode, it has cutoffs that can be set to stop the flow at either time or volume points.) Calibration of this is done at production but can also be done by measuring a specific volume of water in a specific time count with a calibrated scale. It makes brewing onto a scale to measure volume a bit superfluous (once calibration is verified). See Flow and Profiling posts for more relevant discussion.

Right or wrong, it's in the discussion

There is always a balance between art and science in coffee. We tend to approach this as much as we can by eliminating variables and making the art 'the interpretation of the equation', not a few loose variables in the equation. We feel that developing a fundamental understanding of the how and why that fits into one's own personal expression is very important because at it's heart coffee is expression and discussing perfection should be be a matter of opinion. Recently, the discussion has centered around absolute statements such as 'extraction perfection' where some prominent voices believe there is a perfect extraction metric that applies across all coffees, roast styles, water supplies, grind qualities, brew methodologies, brew physics... you get the picture.

I say this because as much as we try to measure and control what we do, the interpretation is in what we produce or more specifically the measure of 'correct' we choose to apply internally to what we produce. You can take a coffee in roast profile to the same drop point a dozen ways or more and the version of 'correct' is really up to the person choosing the profile. The roast errors are definable and obviously unwanted, but that always escapes the discussion.

Over the time I have been in coffee, I have come to the simple realization that there is no right, only what I like and hopefully I find others that agree with this and enjoy it as well. Right and wrong sounds good on paper, when preaching as if it's religion, and in online forums but in truth it's completely subjective, even when standing in the same room cupping together.

Our segment of the professional coffee community that might be reading this though is something of a social networking movement. It is not essentially built on tangible and definable quality, it is built on the conversation about quality. This presents an interesting dynamic where there is nothing cohesive about the companies or many of the individuals lumped together other than working within coffee itself.

So fundamentally, there is a need to control message by many, to be at the cutting edge, that you can see many companies (and individuals) run towards whatever is trending on twitter or being championed on coffeed. Sure, they may abandon it in two months to a year or it makes the kitchen drawer after only a use or two, but that's not the point. Whatever is new and seems cutting edge will be hot for a few minutes until people tire of it and begin looking for the new thing. That's what drives the discussion to have fresh new things to throw against the wall and offer opinions about. A prominent UK blogger/roaster is the prime example of where this creates ripples of noise. His well intentioned 'what if' posts are often to the tune of, I tried this and it was interesting, you try it too. The problem though is that people take the words as facts, as thoroughly researched and proven science which it never was intended as. Empirical notes or scientific method, we should take the latter but it's hard to comment on this unless you are willing to pick up the slack and do the work involved to either prove or disprove statements.

That really doesn't matter expect ironically, the community discussion is always swirling around this moving target of quality and arguing it with vicious statements of absolutism. This presents the simple premise, how can we talk about quality if the brew methods change so often, the coffees rotate so quickly, and the attention span is so short? When our prominent voices in the community are only willing to offer a conversation and strong opinions without offering repeatable scientific experiments to test, we are in murky waters.

A interesting case study would be how the success of the seasonal approach is actually creating a consumption culture among cafes who rotate among roasters. Yes, fresh coffee tastes great... unless it never really gets dialed in or never really hits that mark to live up to the cupping table potential. Let's assume the roaster has the chops to nail the coffee on first arrival and gets the most out of it the first time around. Let's assume there was no feeling out period of getting to know the coffee and avoiding sending out batches that weren't a good representation of the coffee. Let's then assume that all the shops selling it could all dial it in on the first few brews and would be serving it up perfectly in the first week. Then let's erase all of that and start over in two weeks or so. Sound like a reasonable quality system? I would offer it's hard enough to remember the last coffee you enjoyed as a consumer to only come back next week and be confronted with an entirely new roulette wheel of coffees and barista suffer the same overload of 'new'. This is not a criticism but an observation of the plus minus out there.

Here's the real problem I am getting at because I am not really trying to cast stones at big companies or seasonality. We can't say what I just said in those last few paragraphs. In naming the companies or having an open discussion about them with enough inference, I would be assailed by more than a dozen kids who worked for some of the companies talking about how wrong it was and defending the company they work for... until they work for another company.

It borders on group-think where dissent is quashed in an attempt to keep the norm and adhere to the louder voices of the community. If we can't critique and have the serious debates in this industry, then there is no point in having discussion. A little over three years ago, on this blog, we were championing things like getting rid of black box blends, being transparent about ingredients, using progressive packing and storing, and dozens of other crazy ideas at the time that a lot of us were thinking about but few if any had implemented. We took a lot of flack and critique from some prominent voices (who are now quietly on the other side) and were labeled unfairly for our stands. Then some of those ideas caught on with a few big companies and weren't really crazy anymore when proven in the mainstream.

Right now, there is little difference between signal and noise in the discussion. Good coffee is still entirely subjective and having debates about it is only healthy if they are open, have some cynicism and a few dissenting voices to challenge us. Otherwise, it is simply a race to adopt every new toy, be the first to review it then proclaim it amazing, not a discussion about what needs to be fixed and there is an awful lot wrong with our industry. We may be in the middle of a coffee renaissance in the US but it's also a time where idealism runs rampant and egos get big. It's still hard to find a good cup of coffee, still hard to define good, and this movement is still a small segment of a large industry figuring out who it wants to be.

Single origin espresso tasting Dec 4th @ Simon's

Our trainer will be over at Simon's (1736 Mass Ave Cambridge, MA) the 4th for a single origin espresso lineup of four coffees:

Kenya Guama Peaberry roasted by Madcap

Costa Rica Los Lobos roasted by Madcap

Kenya Guama roasted by barismo

Ethiopia Yirgacheffe Michelle roasted by barismo

All four coffees will be offered throughout the morning and into the afternoon.

Check it out!

Happy Thanksgiving!

barismo will be closed Thanksgiving day so stock up early on coffee!

We will be open for a half day on Friday from 8-1pm.

Pressure profiling, flow rate profiling, and the future of temperature profiling

We admit being hesitant to get involved with pressure profiling. Simply put, there were too many problems we had to deal with in accounts to add one more major variable.

Our opinions were refined and changed by first working with Ben and Cora at RBC during a guest stint where we got a few coffees really dialed in using pressure profiling. It was an experience that has continued to get us good feedback on how the coffees come out when the pressure is tweaked. This was further cemented by experiences at Worldbean.

If pressure profiling is the future for a certain market segment, we have to wrap our heads around this a little more and see how it develops. What it points to for us is how the technology in our industry is about to get much more tech very quickly. Keeping up with what is happening and discerning which advances are quality may take some time.

When Clover launched, we were one of the critics of the brewer. The silty metal filtration, the heat wrap issues, and the new brew method it created. We always noted however they were really cool people working there but from a coffee standpoint, we didn't like it. Our opposition to the clover though left us out in the cold in a lot of community discussions because it was what had been trending and everyone was rushing to adopt it so they likewise flamed anyone who disagreed. It took nearly a hundred units being out there before a larger voice of opposition formed and the sale to Starbucks cemented it for many. Now, there are plenty of people against it and still more looking for a new design that doesn't reinvent how we brew coffee, only aids making it.

I am wondering this aloud because as the Lb-1 launches soon, I realize it will take time to seep in exactly the implications of this technology and how it will change how we brew. Sure, we've had versions of this over the last two years and fully get where it's coming from, but there will be many naysayers and many would be early adopters to take that leap.

The fact though is, Luminairecoffee technology will open the door to flow profiling with precision temps. The ability to control and tune flow rate throughout a brew in pour over methods. The following higher capacity version will offer an ability to bulk brew. There's also a top secret project that may show up in a top secret shop opening soon in Cambridge that will be a potential vision of where espresso may go if some of this technology were converted. The current version of the Lb-1 has temperature controls that are unheard of. While the forumphiles and keyboard warriors talk about their different metrics for measuring extraction, we've been lucky to be geeking on something that has precision, repeatable volume/temperature controls making measuring results less useful that observing the inputs. We can even stop and adjust temps mid brew where the pause is only how long it takes to hit a small button sequence. At some point, temperature profiling will be a very real addition, though the requirements to implement it would require much more user interface and would slow production considerably.

So, it could be said, I've had a glimpse of the future. The real revelation is what comes next. These first generation versions of Luminairecoffee technology that will be far surpassing anything else on the market will be the first of a new control that goes beyond previous inventions. While the old engineering maxim of 'fast, cheap, and quality pick two of three' usually applies, this is the exception. Using technology that is cheaper to make and costs less to run (high energy efficiency=cheap), has a zero refresh time (so fast!), and actually produces more consistent and precise temperatures than existing PID'd small boiler technologies(quality).

So some people were commenting how it looks good on paper and how they were skeptical or how it compares it to the boilers out there. I'll file that with the list of things where people have been against something we were exploring, championing, or working with just before it became big in the larger community. Be it as early adopters of specific brew methods, championing progressive packaging, challenging transparency in blends, or the other things we have had detractors line up against, you develop a very thick skin after a while. It all seems to eventually make it main stream or at least catches on enough in small segments that we no longer hesitate to move to back what we believe in.

If US coffee is facing a renaissance of sorts then pressure profiling, flow controls, and temperature profiling are the inevitable. How we get there will either take a long time or be on the backs of small bits of genius that change our entire industry. Here's hoping we are seeing the latter.

It's all about the flow (or it should be)

When talking about v60's and most hand pour methods, the discussion always breaks down quickly with vague terminology. The chatter comes back to a simple and sometimes meaningless statement of total water volume (usually in gram weight), total brew time, and relating extraction %. That's the hot thing right now in espresso as well in drip, to look at the yield, not how you got there.

The truth is that how you got there matters a lot more. In fact, it's everything.

Looking at the end result is myopic but it's easy and makes sense because it doesn't require much investment. Developing the whole picture takes more than just looking at a few parts and will continue to escape us until we become more scientific in our methods and less what if in our blog posts. It is however what's trending so we deal with tons of discussions bogged down by vague statements.

Here is a simple premise. What if we threw out the scale and stopped measuring the results and moved to a discussion focused on flow rate, intervals, and then talk about the yields?

I know, crazy stuff.

Instead of talking about 12oz, 3-4min, and yield... we just say 4oz/min to 12oz at x dose = yield. It makes a lot more sense to really talk about flow, but only if the flow is fixed and measurable. A steady flow rate is easier to make this functional than a stop start method because the real problem with stop n start methods is the inability to accurately repeat what was done. The yields vary greatly and lack consistency. It takes an awful lot of artistic skill to eyeball measure a volume of water and pour small amounts of water at intervals with any kind of repeatability.

This is the entire case for putting a flow restrictor to a kettle to get a fixed and steady stream. It is also the same premise behind the LuminaireCoffee Lb-1. Instead of incorporating a clunky scale (which you can happily buy for around 20 bucks and add on your own) that would cost another thousand to integrate effectively, they put a precision flow meter inline. That means there is a functional and precise measurement on their display of flow (volume over time). This is incredibly useful and rather intuitive once you get used to seeing it. Having that display also makes for less guess work when trying to dial in a brew.

Take the assumption in the next three cases of a 2 cup paper v60 (more elegant in metric but be patient with the oz/min instead of ml/sec):

Case A: You could conceivably brew your preinfusion at 5oz/min over 15sec with a pause of 25 seconds, then brew for 2 minutes at 6oz/min. Total volume of about 12oz if you assume the preinfusion stayed in the brew cake. Total time would be 2:40 plus the 30 seconds (3:10) it took to drain unless the grind was coarser or finer.

Case B: Alternatively, we could conceive a brew with 5oz per minute over 15sec with a pause of 75 seconds. Then follow with one pour at a flow rate of 12oz/min over 1 min sec. With a draw down assumption of 40 seconds (drawdowns are often longer with more aggressive pouring), we'd have a total volume of 12oz in (3:10).

Case C: Finally, we take a 5oz per minute preinfusion over 15sec with a pause of 30 seconds. Then an off on pour of 12oz/min 4 times for 15 seconds with 3 intervals of 20 seconds. (Doing the math to add that up is as confusing as trying to brew it consistently.) The draw down would be roughly 40 seconds making an overall time of 3:10.

With Case C: Making sure you were precise about the intervals/timing/volumes would take an Lb-1 or ninja kettle skills to be repeatable. Case B is the easiest if you don't have a good kettle, and case A is the one if you have a controlled pour or want the most repeatable (less agitation dependent/easier to get repeatable yields from our experiments). These are just examples and a tweak to grind on each could get the same yield throughout at the sacrifice of some time consistency.

In having a discussion, you see people talking about the starting weights, and the ending times/intervals, but there is no discussion about flow. Why? Because it's hard to measure and hard to control. If you had this in your equation and it was easily measurable, you have a real serious (but complex) discussion. Instead of listening to person in case C talk about a pre-wet and then 12oz pour with 'intervals', you could have a repeatable brew equation that can be tested by others with the same coffee. We can record the resistance of a filter then develop a metric for resistance in the grind and how that is changed by the different flow rates (and resulting agitation). Segmenting each interval and testing it would take time but you could actually have a real discussion about what is going on.

Do it in mL per second and the whole thing becomes quite elegant.

Sadly, espresso machines need this most but current designs have no ability to integrate this. A precision display giving an accurate volume over time which would then make measuring yield very useful. Right now, measuring the gram weight then deriving tds and extraction % of a resulting shot (without a specific incorporation of time and flow) is actually a graph of one variable against a derivative of itself. That is not as useful as it seems more than to calibrate yourself with the same coffee on the same machine with the same water at the same temp with the same grinder to repeat a previous good shot of espresso. That is not how it is being used but much like most things in coffee, we talk a lot about things we aren't always doing ourselves.

Having access to these controls has really hardened my belief that there is so much more exploration to be done and we need to be unbound by things like the gold standard. Sure it is great for a bulk brewing traditional cafe but in our segment, what if there is an amazing cup slightly out of that range? Having a precision range of temperatures and being able to switch temperature mid brew has been devilishly fun to work with but also present a contrast to how most people are still stuck at one temp and a declining or a 'sloped' brew temperature. Having precision and easily adjustable flow rates will be the next thing to really play with on the newest version of the Lb-1 (that will be in production in the spring). When other people get them, we'll compare notes and see how the conversation changes.

The state of the local coffee scene

Boston metro is what we always get tagged with. We are in East Arlington. That's right on the border with Cambridge... which is across the river from what is really Boston. Now if you live in Cambridge, you probably don't cross the river much and head into Boston unless you work there.

It doesn't really irk us, just a bit misleading as is the cafe culture in Boston/Cambridge. It's incredibly confusing, convoluted, and a bit of scramble. I can say without a doubt, the better cafes are still in Cambridge right now. After the recent opening of Voltage in Kendall and a few shudders of movement from old Cambridge establishments, things are looking better. Crema got notably better with the addition of Sal (ex Pavement mgr). Toscaninis has put up the money to buy new gear and is moving towards a better coffee program. 1369 got new gear also and doubled down with their coffee program. Simon's recently had two barista place 1st and 3rd after the White Chrome event (local comp hosted by Flat Black) and the shop seems to really have some energy after that. It seems like prepping for the competition and doing well really sparked them (congrats to Nathaniel and Jason). Hi Rise on Brattle St. in Harvard Sq. continues to put out some of the most progressive coffee in the area though the main store on Concord St. has nothing in common coffee-wise (though better sandwiches). That's the roundup of Cambridge shops for now but look for an update to that in a few months.

As for Boston, there are unconfirmed rumors of the coffee MGR of a small chain wanting to a open a barismo style roasting operation on that side of the river very soon, possibly in January (again unconfirmed). We know him and wish him good luck, but it's a lot more hard work than most people expect looking at it from the outside. You run into a lot of walls until you find your customers and if you desire to do quality, the battle is even more uphill around here. Dylan is back working at Sip but we haven't been there recently to check in. Other than that, there is not legitimate motion over there I'd like to note as the rest seems either the same or worse.

Taste in Newton is now owned by GHH/Terroir. I think it's worth a visit to see what they are doing out there. Most of our staff and myself have visited all of these spaces in the last month and you should too. I think visiting all of these cafes is good if you are curious about the Boston/Cambridge coffee scene... as long as you start at barismo... and end there too!

Brew specs for the Kenyas

In shop, they have been playing with the brewing parameters a little for our Kenyan coffees. The Kianjogu can range from the specs on the bag to a higher temp/lower dose and still have a very unique cup. This coffee has such a range and is quite tasty.

We have been playing around with the Guama as an espresso and have had some excellent results over the weekend. After some tweaking and seeing the potential in the coffee, we got a really nice roast that popped. We expect a few people to be serving it up in the next week or two. We are also testing a batch of Soma that will be a Guama edition!

Kenyas!

On the shelf right now are a few Kenyan coffees to look at. The Guama and our Kianjogu are both available. The Guama is a solid and interesting coffee, soon to be offered as an espresso as well.

The Kianjogu has really started to shine and it's probably my personal favorite right now. That coffee bursts with layers, complexity, and juicy sugary fruit. If you are at the shop and have the chance to get a one cup Woodneck brew, you are lucky. Few things can stick in your memory as much as a descriptive flavor experience like that.

The Finca Bu is coming out extremely well. Really floral and sweet. Another favorite to try but this one is going fast. We thought we had enough supply to last us a while but we have been moving this coffee quickly and it looks like we have another month at most to offer it.

For espresso, the Zone 10, our Guatemala/Guatemala pairing has been exceptional. It is currently our most popular espresso offering. To trump that, we are going to up the stakes on the Soma and put a dash of Kenya into it. Should really up the ante a bit.

The coffee is good, see you in shop!

barismo tasting event at Dave's Nov 13th 1-3pm

We will have a free tasting event at Dave's Fresh Pasta in Davis Sq., Somerville November 13th from 1-3pm!

An offering of our new coffees will be served up in samples. Our roaster and green buyer will be there to talk about how we get these coffees and what it takes to get the most out of them.

See you there!