Study of Maturity Fruit Assessment using Permittivity and Microwave Reflectivity Measurements for Quality Classification

This paper aims at the non-invasive analysis of fruit quality using Split Ring Resonator sensor and correlating the results with dielectric variations in the fruit due to ageing. The microwave split ring resonator sensor (SRR) is used differentiate between fresh and aged Red Grapefruit (Citrus Paradisi) over the frequency band ranging from 1–10 GHz over 1 day to 2 weeks measurement time points. A relative difference, in the mean epsilon (over 5 samples) values between the good and aged grapefruits, of 30% and 40% are found for the real and imaginary part of the permittivity respectively over the S-band frequency range. Corresponding shift in resonance frequency of SRR is also observed.