Effect of moisture on dielectric behavior of gluten-free grains in powder form at microwave frequencies

Abstract

Dielectric constant ([Formula: see text]) and dielectric loss factor ([Formula: see text]) of gluten-free grains viz., Finger millet, Amaranth and Buckwheat in powder form were measured at room temperature (22∘C) at frequency 9.76[Formula: see text]GHz for different moisture content samples. The method used was the Two-Point method which is based on the transmission line technique. Microwaves were employed to investigate dielectric properties and their moisture dependence. The results showed that dielectric constant and dielectric loss of Gluten-free grains increase with the increase in moisture content. It shows that for higher moisture there are more free molecules in comparison to bound water molecules. This work can be an effective guide in designing a moisture meter for gluten-free grains.