Foam-mat drying of lucuma powder: Mathematical and artificial modeling of drying kinetics, physicochemical and microstructural properties

Abstract

The kinetic study of foam-mat drying to make lucuma powder was conducted at various drying temperatures (50–80oC) using thin layer drying and an artificial neural network (ANN) to forecast drying behavior. The physico-chemical properties of lucuma powder under these conditions were also analyzed. Among the six models, the parabolic model was chosen as the best appropriate model for describing the lucuma drying process with the highest correlation coefficient, the lowest RMSE and Chi-square. However, the ANN model (2-10-1) could predict the moisture ratio more accurately than the parabolic model, and it also presented the fittest with the actual experiment. As temperature increased from 50 to 80oC, effective moisture diffusivity increased from 1.05 × 10-9 to 1.67 × 10-9 m2/s, with an activation energy of 15.12 kJ/mol. Drying temperatures have a considerable impact on the quality of lucuma powder. When dried at 60oC, lucuma powder had a bright yellow color, retained its quality and excellent antioxidant activity compared to other temperatures evaluated simultaneously.

Keywords

• Drying kinetics
• Foam-mat drying
• Lucuma
• Physico-chemical properties
• Microstructure