Drying kinetics of guabiju pulp (Myrcianthes pungens): Mass transfer parameters, mathematical modeling and evaluation of bioactive compounds

This work aimed to estimate the mass transfer parameters of guabiju pulp under different temperatures of drying, modeling the kinetic curves using Fick's second law and the Lewis, Henderson-Pabis, Page, Modified Page, Logarithmic and Midilli models and to evaluate their biological properties and color. Guabiju pulp were dried at 313.15-373.15 K. The drying rate decreases over time, showing an exponential behavior with a significant influence of the operating temperature. Values of the effective diffusivity coefficient (D-eff) between 1.578 and 10.755 x 10(-9) m(2) s(-1) were observed, with an activation energy of 30.77 kJ mol(-1) and an Arrhenius factor of 1962 x 10(-4) m(2) s(-1). All models used showed good fit quality parameters (coefficient of determination-R-2 (> 0.9521), sum of squared error-SSE (< 0.0049), root mean square error-RMSE (< 0.0699) and chi-square test-X-2 (< 0.0052)). The Midilli model showed the smallest deviations in relation to the experimental data. The values of the mass transfer constant (k(6)) ranged from 0.00036 to 0.01232 for the Midilli model. The best results for antioxidant activity, phenolic compounds and flavonoids were obtained at 353.15 K. The dehydrated guabiju pulp can be considered promising for human consumption and for food supplementation due to its biological activities, since the phenolic compounds act as pigments, flavor precursors and natural antioxidants. Practical applications Drying systems have proved to be an important strategy for the conservation of natural resources. However, they still lack studies by society. In line with drying systems, the kinetic modeling of the data allows simulating and optimizing the process, reaching the maximum potential of the process and making the process viable, reducing losses and errors and increasing product quality, facilitating industrial implementation and scale-up. Thus, studies on the drying of guabiju pulp (Myrcianthes pungens) help to understand the process. Considering that the fruit has bioactive compounds and can be used in a certain product within the pharmaceutical, chemical or food industry.