Estimation of starch content in cassava based on coefficient of reflection measurement

Abstract

This technology report validates the application of radio frequency (RF) coefficient of reflection (Γ) measurement as a viable and accurate means to estimate the starch content of fresh cassava roots. A clear relationship between cassava dry matter as an indicator of starch content and the Γ is experimentally verified both from the measurement of cassava flour in water at different concentrations and by direct probing of cassava root samples at a specific frequency of 30 MHz. A prototype test instrument designed with goals of portability, low cost and ease of use is also reported. The test instrument displays estimated starch content in five categories, from “low” to “high”, using an array of five LEDs. The performance of the test instrument is experimentally verified in the field, and a reliable correlation between cassava dry matter content and LED indication is demonstrated.