Nondestructive Evaluation of Moisture Content for Spinach Leaf Powder Using Complex Impedance Spectroscopy

Highlights Complex impedance spectroscopy (CIS) is applied as a nondestructive tool. Impedance and capacitance approaches have been explored to predict the moisture content. The logarithmic function of impedance to capacitance predicts the moisture content precisely. Abstract. Complex impedance spectroscopy (CIS) is a powerful, nondestructive method to study the electrical properties of biomaterials. The electrical properties of spinach (Spinacia oleracea) leaf powder was used to investigate the moisture content using the nondestructive approach. Frequency-dependent relationships of impedance and capacitance with moisture content in various combinations have been explored to predict the moisture content precisely. It was found that the logarithmic function of impedance to capacitance could be used to predict the moisture content precisely in the under-investigated frequency range (1–10 MHz) with the highest accuracy, as confirmed by the found statistical support. Keywords: Complex impedance spectroscopy, Moisture estimation, Nondestructive testing, Spinach.