Thermal and Kinetic Properties of Brazilian Coffea Arabica Beans

Abstract

The chemical composition of green coffee beans depends on the number of parameters, such as coffee cherry processing methods, used. The quality of roasted coffee is related to the certain substances that developed during the roasting process and that are responsible for the organoleptic properties. The main objective of this study was an investigation of the thermal behaviour and the fatty acids profile of green and roasted Brazilian Santos coffee beans. The glass transition temperature was measured using modulated differential scanning calorimetry (MDSC). The thermal behaviour of coffee samples was evaluated by means of thermogravimetry (TG) and first derivative thermogravimetry (DTG). The oxidative stability and kinetic parameters were characterized with the use of differential scanning calorimetry (DSC). According to the TG and DTG curves, coffee samples showed different behaviour of thermal degradation in the atmosphere of oxygen and nitrogen. Our research shows that the thermal properties and fatty acids profile did not change during the roasting process.

Keywords

• thermal behaviour
• glass transition
• coffee fat
• fatty acids