Coffee beans microstructural changes induced by cultivation processing: An X-ray microtomographic investigation

The present work reports on the microstructural characterisation of four types of different processed coffee beans, Coffea arabica, Arabica monsooned, Coffea canephora and Robusta monsooned, by means of X-ray microtomography technique (μCT). A three dimensional (3-D) quantitative analysis was carried out on the microstructure the bean samples before and after roasting. The 3-D microstructure information provides a better understanding of the structure of the beans and from an engineering perspective; knowledge about the microstructure can be used to identify the important processing parameters that affect the quality of coffee. With regards to the microstructure, the porosity increase can summarise the overall effects of the roasting process on coffee beans. Results demonstrate the success of μCT for the quantification of the microstructural alterations of the coffee beans induced by their different cultivation processes before and after the roasting process.