Water sorption properties of coffee fruits, pulped and green coffee

作者：Goneli A L D; Correa P C; Oliveira G H H^*; Afonso Junior P C

来源：LEBENSMITTEL-WISSENSCHAFT UND-TECHNOLOGIE-FOOD SCIENCE AND TECHNOLOGY, 2013, 50(2): 386-391.

DOI：10.1016/j.lwt.2012.09.006

• GAB model
• Coffea arabica L.
• Wet method
• Enthalpy
• Entropy
• Gibbs free energy

Thermodynamic properties of coffee in three different forms (green, pulped and coffee fruit) were obtained during the desorption process. Desorption was accomplished by static method using saturated salt solutions, providing relative humidity range of 11-95%. Five different temperatures were utilized (10, 20, 30, 40 and 50 degrees C). Equilibrium moisture content data were correlated by the Guggenheim-Anderson-de Boer model, which presented good fit to the data, according to statistical procedures. Equilibrium moisture content ranged from 4.34 to 10.75 g/100 g dry solids. Enthalpy values for each model coefficient were estimated, ranging from -8.09 to 82.64 kJ kg(-1). Differential enthalpy and differential entropy increased with decreased equilibrium moisture content, which was also found for Gibbs free energy. Coffee fruits presented higher values of these thermodynamic parameters.

• 出版日期2013-3