Estimating moisture content and physical properties of sweet potato based on the multiparameter of electrical impedance spectroscopy.

A multiparameter method is proposed to research the relationships between electrical parameters and moisture content of the sweet potato. Moisture rate, surface states, and shearing stress of samples were measured, which was dried at a temperature from 50 to 90°C, respectively. The proposed multiparameter consisted of three characteristic parameters, namely, Zintra, Zc, and Zextra based on the electrical impedance spectroscopy. The correlations of characteristic parameters with moisture rate and shearing stress were analyzed by multiple linear regression analysis. Results showed that the multivariable regression was better than the univariate in the correlations with moisture rate and shearing stress, and the 2-variable regression was superior to 3-variable in shearing stress. The multiparameter method is proved to have a positive effect on analyzing moisture content and physical properties of sweet potato. [ABSTRACT FROM AUTHOR]