Effect of moisture content in beef on reflection and dielectric measurement using coaxial reflection probes

Abstract

Open-ended coaxial probe and Agilent 85070E High Temperature Probe were used in conjunction with Agilent E8362B PNA Network Analyzer from 200 MHz to 20 GHz for moisture detection in beef. The open-ended coaxial probe was fabricated from SMA stub contact. A high-temperature probe was used to measure dielectric properties, ϵ∗ viz. dielectric constant, ϵ′ and loss factor, ϵ″ of beef. Complex reflection coefficient, Γ was measured for different moisture content (mc) of beef. It would be compared with the measured Γ from High Temperature Probe to verify the performance of coaxial probe. ϵ′ increases when mc increases. However, ϵ″ exhibit opposite response with mc. Measured |Γ| via both probes decreases when frequency and mc increases. Meanwhile, negative phase, - φ increases due to the increment of frequency or mc. The results show that measured ϵ and Γ provides significant results for predicting mc. However, φ is indistinguishable among different mc of beef.