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Abstract Results Dielectric measurements were performed on several food types, which include apple fruit, meat, and two types of fish (Tilapia nilotica – Mugil capito). The effects of storage time on the dielectric constant were investigated. The uncertainly in the measured data is expressed as standard deviation and is indicated in the figures by the error bars. The frequency range of the applied field is from 10 KHz to 1 MHz It took about 2.5 min for a single scanning to cover the entire range. The scanning is repeated five times and the standard deviations were calculated at each frequency. 4-1 Apple fruit samples The results of apple dielectric measurements are summarized in (Figures. 9-13). (Figure 9a) shows a typical set of the frequency dependence permittivity of an apple sample at different storage periods (1,2,3,4,5,8, and 15) days. The real permittivity (’) decreases rapidly with increasing frequency and the permittivity spectrum curve shifts down with increasing the storage time. (Figure 9b) shows the frequency dependence conductivity at the same periods. The conductivity () increases as a function of frequency and reduction was obtained with increasing the storage ti |