Changes Of Some Engineering Properties Of Coffee Beans Due To Roasting Process

Abstract

The changes in physical, mechanical, and colours after roasting in two-level were investigated. Aims of this study were to evaluate changes in the physical, mechanical, and colours due to the roasting process of the Arabica and Robusta coffee bean grown in Cisalak Sub-District, Subang District-West Java. Results of analysis determined that the roasting process resulted in decreasing the moisture content of green coffee bean from 13.8% to 6,54% of first-level roasted bean and 6.24 of the second-level roasted bean, while that of robusta decreased from 11.22% to 7.56 and 6.12%. First-level roasting was categorised as a light roast, while the second-level was a medium roast. The Roast Weight Loss of arabica and robusta from green to light roast bean were 19.45 % and 16,24%, respectively, and that to medium roast bean was 26.20% and 22.37%, respectively. The roast volume change of arabica and robusta from green to light roast bean were 50.55% and 44.30 % respectively, and that to medium roast bean were 54.65% and 55.92 % respectively. The total colour differences between green with light and medium roast bean of arabica were 6.39 and 2.52, while that of robusta were 6.19 and 2.49, respectively.