JOURNAL OF FOOD PROCESSING AND PRESERVATION, cilt.44, sa.5, 2020 (SCI-Expanded)
The aim of this research was to determine the adsorption behavior of coffee as green and roasted beans and ground. For this aim, the static gravimetric method was used and samples were kept in the different water activity levels between 0.01 and 0.91 at 25 degrees C for 7 days. The data were evaluated using the BET (Brunauer-Emmett-Teller), GAB (Guggenheim, Anderson and deBoer), Halsey, and Peleg sorption equations. The constants m(0) and C of BET and GAB equations were determined to be between 2.13 and 6.61 g water/100 g of dry matter and 30.05-429.60, respectively. The isotherms of all coffee samples were defined as Type II because the C constant of the GAB equation was higher than 2. Additionally; the BET, GAB, and Peleg equations were determined to fit better than the Halsey for adsorption properties of coffee because E% values were lower than 10% and the coefficient of regression values approached the 1.00.