PROFILE Probat
The new Colour Control system mounted on the Px 120 drum roaster.
COMPLETE COLOUR CONTROL PROBAT’S NEW COLOUR CONTROL MEASUREMENT SYSTEM HELPS INCREASE ROAST TIME PRECISION THROUGH LINKING LIGHT SIGNALS WITH COFFEE BEAN COLOUR.
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rom pioneering the spherical commercial roaster in 1870 to manufacturing the first tangential roaster in 1969, Probat has always strived to provide the best coffee processing solutions, and continues to evolve the artform today. Typically when roasting, a combination of time and the coffee bean’s end temperature is used to predict colour and aroma of the final product. However, Probat’s Head of Product Management, Oliver Böwing, and PLC Programmer Tim Ambrosius, say this method is flawed. “We have known for a long time that a longer running machine results in a different temperature equilibrium. Heat is transmitted into the machine and there is heat transmitted when the coffee is moved outside the machine. It’s not always the same temperature base,” says Böwing. Using Probat’s new Colour Control system in combination with time and temperature parameters, Böwing says roasters can now consistently and accurately reproduce the same coffee profile. “The colour sensor compensates for the unstable heat within the machine and, since it is not directly linked to the roast, can detect changes quicker,” says Böwing. This, combined with the system’s ability to record the coffee’s properties without interfering with the roast process, alongside the real-time transference of data, offers huge advantages to roasters. “Previously, it was hard to track the roasting process from outside the machine, but with this Colour Control system, roasters are now able to react quicker,” says Böwing. “Roasters can detect if a coffee blend is different to the set recipe just by seeing the switch in colour. This can be done instead of the traditional method of checking the temperature with a
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probe, taking a sample of the coffee beans to the lab, grinding it, and then checking whether it is correct.” Böwing says this method slows down roast production times. Probat’s Colour Control fixed sensor system consists of a measuring probe, a computational unit, and two infrared lightemitting diode (LED) lights that are placed in a switch cabinet outside the roasting drum. The light of the LEDs is transmitted via a fiber optic cable into the drum. “This system has the [the computational unit] inside, constantly analysing the roasting process and controlling the sensor probe itself, acting upon information from the light,” says Probat’s PLC Programmer Tim Ambrosius. “We collect data from the reflected light shone by the two LEDs using special smart sensor equipment.” This reflected light is recorded as
