| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 764.92 KB | Adobe PDF |
Advisor(s)
Abstract(s)
This paper presents an experimental study on the evolution of carrot properties along convective drying by hot air
at different temperatures (50ºC, 60ºC and 70ºC). The thermo-physical properties calculated were: specific heat, thermal
conductivity, diffusivity, enthalpy, heat and mass transfer coefficients. Furthermore, the data of drying kinetics were treated
and adjusted according to the three empirical models: Page, Henderson & Pabis and Logarithmic. The sorption isotherms
were also determined and fitted using the GAB model. The results showed that, generally, the thermo-physical properties
presented a decline during the drying process, and the decrease was faster for the temperature of 70ºC. It was possible to
verify that the Page model presented the best prediction ability for the representation of kinetics of the drying process. The
GAB model used to fit the sorption isotherms showed a good prediction capacity and, at a given water activity, despite some
variations, the amount of water sorbed increased with the decrease of drying temperature.
Description
Keywords
kinetic model mass transfer coefficient enthalpy thermal conductivity diffusivity heat transfer coefficient
Citation
Guiné RPF, Gonçalves JC, Calado ARP, Correia PMR. (2016) Evaluation of thermo-physical properties and drying kinetics of carrots in a convective hot air drying system. Agricultural Engineering International: CIGR Journal, 18(3), 245-257.