Publication . Santos, João Rodrigo; Viegas, Olga; Páscoa, Ricardo N. M. J.; Ferreira, Isabel M. P. L. V. O.; Rangel, António O. S. S.; Lopes, João Almeida
In this work, a real-time and in-situ analytical tool based on near infrared spectroscopy is proposed to
predict two of the most relevant coffee parameters during the roasting process, sucrose and colour.
The methodology was developed taking in consideration different coffee varieties (Arabica and
Robusta), coffee origins (Brazil, East-Timor, India and Uganda) and roasting process procedures (slow
and fast). All near infrared spectroscopy-based calibrations were developed resorting to partial least
squares regression. The results proved the suitability of this methodology as demonstrated by rangeerror-
ratio and coefficient of determination higher than 10 and 0.85 respectively, for all modelled parameters.
The relationship between sucrose and colour development during the roasting process is further
discussed, in light of designing in real-time coffee products with similar visual appearance and distinct
organoleptic profile.
