Moisture desorption behavior and thermodynamic properties of pulp and seed of jambolan (Syzygium cumini)

Adriano Lucena de Araújo; Rosinelson da Silva Pena

doi:10.1016/j.heliyon.2022.e09443

Moisture desorption behavior and thermodynamic properties of pulp and seed of jambolan (Syzygium cumini)

Heliyon. 2022 May 15;8(5):e09443. doi: 10.1016/j.heliyon.2022.e09443. eCollection 2022 May.

Authors

Adriano Lucena de Araújo¹, Rosinelson da Silva Pena^{1

2}

Affiliations

¹ Graduated Program in Food Science and Technology, Institute of Technology, Federal University of Pará (UFPA), 66075-110, Belém, Pará, Brazil.
² Faculty of Food Engineering, Institute of Technology, Federal University of Pará (UFPA), 66075-110, Belém, Pará, Brazil.

Abstract

The study objectives were to establish isotherms and thermodynamic properties for the moisture desorption process of jambolan pulp (JP) and jambolan seed (JS), harvested in the city of Belém (Brazil). These characteristics can contribute for the proper selection of the operating drying conditions. Thus, the following essays were made for both JP and JS. Firstly, proximate composition was performed, followed by moisture desorption essays at 25, 35, 45 and 55 °C. In addition, six mathematical models were fitted to the experimental data to simulate the desorption behavior; and based on the chosen models, the thermodynamic properties were calculated. The results have shown that JP isotherms followed the typical behavior of products rich soluble solids, and JS isotherms were more influenced by protein components. The influence of temperature was evidenced throughout the entire range of water activity (a_w) studied. The GAB and Oswin models represented the best fitted equations for the JP and JS, respectively. In general, the energies involved in the desorption process of jambolan showed a greater dependence of JP with the equilibrium moisture content (EMC), in comparison with JS. Still, there was an increasing tendency of the thermodynamic properties with EMC decreasing. Besides of being non-spontaneous processes, desorption phenomena of JP and JS were enthalpy-driven mechanisms.

Keywords: Equilibrium moisture; Mathematical modeling; Myrtaceae; Thermodynamics.