Toward an approach for moisture estimation during hot air drying of neem leaves (Azadirachta indica) using pulsed phase thermography

Drying agricultural products allows farmers to extend the life of their products for a longer time. In recent years, nondestructive testing provided an alternative to moisture estimation in the dehydrated products industry. This work improves a methodology to estimate moisture based on pulsed thermography. Furthermore, to demonstrate the principle of operation, an infrared camera monitored evolution across time from dry leaves stimulated with a heat pulse; a heat-response curve was generated from the images sequence, and several regressions (linear, polynomial, exponential, among others) related the moisture content to the reaction to the heat stimulation. Cross-validated best results, 0.91, 0.085164, 0.0072529 and 0.068838 of R-squared, RMSE, MSE, and MAE, respectively, indicated that pulsed thermography is an efficient method to estimate the moisture content in neem (Azadirachta indica) leaves.