Coffee Cup
"Espresso! My Espresso!"
An Ongoing Internet Novelette
by Randy Glass - Copyright 2020 - All rights reserved

Coffee Cup
161
Consistency, Control, Technology,
and the March of Time

Thursday, April 16, 2020
all text and photos ©2020 - All rights reserved

   I have been living in a 34-by-10-foot RV for about fifteen months and back on my own property for about six months. Besides having the time to achieve 'level 855' on the game app “Wordscapes,” I have lots of time to think. Over the recent weeks of contemplation as I was shopping for a new espresso machine I began to reminisce over the the last twenty years and realized how remarkable the developments in espresso “technology,” have been.
   Over those two decades the various discoveries, experiments, and hardware modifications that have gone on in the labs and homes all over the world have gone a very long way towards quantifying the parameters that make a great espresso and at the same time made it easier to control and achieve those parameters.
   For the sake of this article I would mark the birth of that 'Enlightened Era of Extraction' when enthusiasts like Greg Scace, Andy Schecter, and many others on the Usenet group, “alt.coffee,” installed PID controls on Rancilio Silvia espresso machines to control boiler temperature. This precision control of the boiler temperature proved that this particular machine was far more capable of creating excellent espresso than it had been out of the box using the factory's snap thermostats. Before this there were variations on the theme of flush-and-time-and-brew in order to create some sort of repeatable temperature starting point for initiating extraction. This was less than efficient in terms of water waste alone, and the accuracy was questionable as well.
   We knew that temperature control in espresso extraction was important but the control made available by the installation of PIDs by many home users drove many of us to experiment with different temperatures and this began a wide range of experimentation and data gathering. A PID allows precise temperature control of the water inside the boiler, the most important temperature is when the water hits the coffee. The next great moment in those times was the invention of the “Scace Device” by Greg Scace. A tool that can precisely measure the temperature of the water hitting the coffee cake in real time. Without overstating this, the Scace Device has become an industry standard for such measurements.
   To get back on point, I am not sufficiently knowledgeable to be able to document the history of such efforts before or after that time, nor do I have the desire to do so. But what brought me to this point is that I was recently invited to read and suggest edits of a transcript of a review of Greg concerning a lot of what I have mentioned here. That is what led me to the creation of this introspective.
   The difference between what machines were available when I began in late 2000 and what is available now, two decades later, is quite astounding. When I bought my Silvia in late 2000 there were not many good choices for home baristas. Below the single boiler, dual use machines were “steam toys,” and above them were mostly commercial machines.
   Much like “real” control over temperature, other parameters of espresso extraction have been experimented with and recognized as having a significant if not a profound effect of the beverage. Historically, Faema's E-61 group brought pre-infusion to the semi-automatic machines, emulating one part of what baristas using lever machines had been doing for decades; manually controlling the flow of water and controlling brew pressure. Much later, dual-boiler machine designs trickled down from the commercial offerings to the home market. This allowed the brew boiler to be filled with just water and a separate boiler for hot water and steam.
   We are now at a point where machines are beginning to be available with levels of control previously unseen even in any espresso machine, commercial or not. We now have available machines with flow control, pressure control, and temperature control. Real time monitoring and digital displays can show various parameters, and controls of those parameters allow changes before and during the extraction. Pre-programmed parameters can control the extraction without input from the barista, and manual controls of an extraction can be saved to be used later.
   And now, some of the functions mentioned above can be found on a machine here and a machine there. For example, flow control has been added to E-61 groups using a needle valve to replace the gicleur and controlled by a group-top, manual rotary lever. I feel this is a simplified attempt to bring some of the control over the brewing process that has always been available in manual lever machines. The next technological step is to digitally control this parameter.
   One machine currently allows pre-programming of pressure profiles which control the entire extraction. Another offers that as well as manual control of pressure during the extraction, and that user-created curve can be saved upon extraction conclusion. And now, as of this writing, there is a machine which offers temperature, flow, volume, and pressure control. I feel that this machine points towards the future.
   There was a discussion about five years ago concerning superauto machines which would be able to create very good, if not excellent espresso repeatedly. The functions of the advanced machine mentioned above indicate that this prediction was not so far-fetched as it sounded at the time. These machines point towards a time when fully automated espresso creation (“Ultra-Super-Mega-Auto”?) machines may be able to compete with the best of coffee shops. For any given blend and roast, there is a set of parameters that will create the best espresso possible from those beans (“best” being a relative thing, of course). If you have a machine that can fully control pressure, flow, temperature, and water volume precisely, it is a short step to incorporate that technology into a machine that also includes a quality, single-dosing grinder controlled in much the same way. And someone is actually working on this as we speak.
   What if you could walk up to a machine, press “Ethiopian” on a screen, choose “cappuccino,” and select “double,” and even select which milk to use among the various choices, pass your credit card over the indicated area, and voila! The Master Espresso Vending Machine serves up a delicious beverage. This could be just around the corner! Laugh if you must, but in Japan there are vending machines that sell used ladies' panties. I won't ask which you would prefer, but I will take the Ippai no kohi (cup of coffee). What if it were a home machine with a Q-code reader. Show the machine the code on the bag and it sets its parameters as chosen by the roaster.
   If that sounds like an episode of “The Jetsons,” it may be, but likely only for the need of a market to accept it. Dream or reality, all the technology to achieve it already exists. If we rule out the futuristic super-auto functions, the “Decent Espresso” home espresso machine is currently available and it can control these parameters:
  • pre-infusion time and volume
  • extraction pressure profile
  • extraction flow profile
  • brewing temperature profile
  • steam temperatures
  • beverage water volume
  • hot water dispensing volume and temperature
  • total beverage mass using a bluetooth scale in real time
       All of that in a compact machine (roughly 13” x 9” x 18”) that has no boilers and sells at a starting price of about $2800. That was approximately the street price of my double boiler, PID E-61 espresso machine when I received it which 'only' had PID control of brew boiler temperature.
       In terms of home machines, these advanced machine features are appreciated (and mostly purchased) only by those who live nearest the tip of the espresso pyramid. Whether you call them (or us) connoisseurs, foodies, geeks, hipsters, or lunatics, all areas of food have those who dedicate themselves to creating the best possible experience. Whether it be artisan bread, artistic desserts, pizza made with home-ground wheat and home grown herbs, or simple foods like refried beans from scratch or homemade kimchi, the enjoyment of quality food is something too few ever pursue or experience.
       But much like the experimentation with PID devices by coffee geeks led to them being installed in all levels of retail espresso machines, this new multi-faceted level of control will find its way into a lot more homes at a cost less than we paid for Silvia twenty years ago. Raise an eyebrow to that statement, but who would have thought twenty years ago that antilock brakes, traction control, and accident avoidance would be so widely available two decades later?
  • Coffee Cup
      -   -   - Silvia
    Home
      -   -   -
    To Next Chapter