Coffee Roasting – ‘A Flavour in Motion’

Unlike its complimentary beverage, green tea, the green coffee bean (un-roasted bean) has little flavour and is not consumed in its natural state. Coffee beans require roasting to bring out their flavours and aromas, and this usually takes place at high temperatures within a coffee roaster, where the necessary internal chemical reactions can occur within the coffee bean and within a controlled environment.

Most coffee roaster heat source is driven by gas flame, but other heat may include electricity and wood-fired flame. Further, the technology of the roast process may differ dramatically from one machine to another. These include, horizontal drum, vertical fixed, rotating paddle, swirling bed, spouted bed and fluidized bed coffee roasters. Temperature of roast, roast times, plus convective and or conductive heat also varies within these roasting options used by the coffee industry.

The associated images included with this article, show roasting by the fluid-bed process. Also they show the colour changes of the coffee bean within the roast process. The success of fluid-bed roasting lies within the fact, that this roast technology uses only convective heat to activate the necessary chemical changes during roasting. Further to this, the coffee beans are in continual fluid movement within the roast chamber (see images), ensuring even roasting within constant moving hot air. Flavours and aromas develop in motion with an even colour, and most importantly, a consistent flavour profile, for the consumers enjoyment.