RoastPATH : Roast Precision Reinvented.

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We’ve spent thousands of hours engineering 12 various sized roasting machines uniquely built to answer the demands of modern specialty coffee production. The result is that Mill City Roasters now produces the most powerful, heaviest built, most controllable, and most uniquely instrumented commercial coffee roasters in the broadest range of sizes ever offered.

While better machine design is enormously important to the development of operator skill, and by association coffee quality and consistency, it turns out there’s a whole lot of room for improvement in terms of information technology and machine control.

RoastPATH is a collaborative platform for industry professionals. On the logging side, every MCR machine uses RoastPATH as a roast feedback loop allowing the operator to see changes in the roast environment, anticipate impactful deviations, and take corrective action.

On the QC side, RoastPATH allows operators to designate and create masterpath roast profiles relative to results at the cupping table. It also allows users to share roast profiles, greens, and cupping results within a group of professional collaborators of their own choosing and even in real time during a roast.

Beyond automation, all digitally controlled Mill City machines are capable of highly advanced operator assist roast replay and machine control functions allowing increased equipment utilization by entry level operators with potentially enormously higher quality roast outcomes relative to industry standard “dumb” stepped temperature autopilot automation.

Standard data collected during the roast on every Mill City roaster:

  • Bean Temperature: allows the operator to understand seed temperature in real time
  • Drum Temperature: records most accurate pre-heat temperature for more precise between batch procedures
  • Environmental Temperature: allows to the operator to predict upcoming changes in bean temperature in real time
  • Fan Speed: increases consistency in convective heating from minute to minute and batch to batch
  • Drum pressure: feedback mechanism for real time fan speed and airflow effects.

Standard data on every digitally controlled studio and production roaster:

  • Logging and display of drum temp: for more precise preheat
  • Logging and display of Bean Temperature, Environmental Temperature
  • Logging and display of Incoming Air temperature: to avoid excess heat and heat defect
  • Logging and display of Drum Speed
  • Logging and display of Fan Speed
  • Logging and display of Gas Pressure
  • Charge, discharge, and cooling tray discharge.
  • Automated roast timer activation
  • Automated between batch protocol recovery temperature programming
  • Automated stirring arm and cooling tray fan activation

RoastPATH Automation:

  • Proprietary automated pre-heat algorithm to manage latent heat energy for precision preheat.
  • Automated between batch protocol recovery.
  • Precision production roast execution from charge to discharge.

RoastPATH Collaboration:

  • Unlimited greens, coffee, and roast data sharing
  • User forum with participants ranked by real roast metrics
  • Greens database pre-populated by Cafe Imports and Genuine Origin
  • Import and export .alog and csv files
  • Direct to print and digital media sharing


  • Modbus, USB, Bluetooth
  • Windows, Mac, IOS, Android
  • Custom communication configurations and devices available.

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