Consistent roasting technologies

Working in an industry that deals with a natural commodity comes with its drawbacks. From hoping for good weather for an abundant crop, or that a particular farm will be spared rust disease or berry borer, the humble coffee bean is very much at the mercy of mother nature. Once the bean has successfully been grown, harvested, processed, and transported to a roasting operation, it’s of little surprise that true consistency within a single lot is virtually impossible. The consumer, however, is harder to convince on the challenge of consistency, as he or she is simply interested in the resulting quality in the cup. This is the main crux of the problem that roasting operations have faced since the coffee bean first touched heat. Add in additional factors like the outside temperature where the beans are being stored, the temperature of the roaster depending on the time of the day, and even atmospheric conditions – the list of challenges to achieving consistency in roasting operations just keeps growing.   This is where technology can come in and save the day. In this edition of Global Coffee Review, we speak with four industry leaders in the production of roasting equipment. While every company representative acknowledged the importance of the roastmaster in achieving a desirable flavour profile, they also offered impressive technological advancements to confront the challenges imposed by these external factors. Thomas Koziorowski Director of Product Technology and R&D at Probat (see here), explains that in large scale operations working with pre-blended beans, consistency must be delivered on different layers. The first being the standard parametres considered in roasting profiles, that is colour, time, and roast temperatures. The second layer is the need to limit the “demixing effect” that can occur when roasting a blend. To limit this demixing process, he explains how Probat equipment allows operators the possibility to adjust the mixing movement and roast air flow separately. Andreas Juerss, Marketing Manager at Neuhaus Neotec, emphasises why versatility is key in achieving consistency in roasting operations (see here). He says that the machine must be able to finely adjust the variables as needed. This is where Neuhaus Neotec’s position as leaders in hot air roasting technology, he says, largely comes into play. With hot air roasting, the machines have a higher heat capacity in the system itself, leaving more flexibility to adjust parameters like temperature and air flow to ensure the optimum profile. Mark Loring Ludwig, Founder of the Loring Smart Roast (see here) says that the link between top roastmasters and Loring is the equipment’s ability to cater to the list of roaster-oriented factors that affect consistency of the colour and flavour profile of the coffee products produced on it. On top of this, Loring equipment operates with a 100 per cent premix burner. Air and gas are always mixed in exactly the right amounts, so there is nothing of either left over. This means that the external room temperature, atmosphere, weather and time of year will not affect the roast. At Buhler (see here) part of the answer comes in the form of what Stefan Schenker, Head of Market Segment Coffee, calls “real profile roasting”. Technically called IRC Process Control, this is a highly reactive system that modulates the energy input into the system depending on the actual temperature of the bean. The result means that no matter the external factors, the same roast profile can be achieved right from the first batch.