From Table 1 it can be noted that the coffee beans subjected to the conventional, combined conventional-vacuum and vacuum processes reached comparable weight losses at a similar F value of approximately 20 min, which was attained at 30, 40 and 45 min roasting, respectively. According to the literature (Clarke, 1987), this weight loss value corresponded to a dark degree of roast. It is noteworthy that a medium degree of roast, accounting for weight losses ranging from 6% to 8% (Clarke, 1987), was achieved by applying F values of approximately 3.9 and 4.2 min for the conventional and combined conventional-vacuum processes respectively, and 1.6–3.8 min for the vacuum process (Table 1).