EFFECTS OF FREEZING ON IMPEDANCE OF RAINBOW TROUT (Oncorhynchus mykiss)

The aim was to examine the electrical characteristics of rainbow trout (Oncorhynchus mykiss) fillets subjected to different freezing methods. Resistance (R) and reactance (X) were measured in the range from 1 Hz to 1MHz on 100 samples and recorded data was analyzed by principal component analysis (PCA). Results of principal component analysis showed that the results of resistance and reactance measurements can be extracted into 3 principal components. Results of discriminant analysis showed that the use of principal components, physical and chemical measurements, it is possible to correctly classify 77% of samples. It was observed that the reactance measured at medium and high frequencies is sensitive to changes in the structure of trout fillets due to different freezing methods.