Bio-impedance measurements for meat quality determination of pork loins under repeated freeze-thaw treatments

Abstract

Evaluation of key quality traits in the cold chain is an important factor in ensuring meat safety. To meet the demands of consumers, development of non-destructive detection methods is essential for quality assessment of meat products. Electrical impedance spectroscopy (EIS) has emerged as one promising non-destructive technique in the food industry. In this study, EIS was developed to investigate the effects of freeze-thawing on quality parameters of porcine meat. Bioimpedance from 20 Hz to 200 kHz was collected from frozen-thawed meat, and the experimental impedance data were fitted to a Cole impedance model. The model fitting resulted in corresponding determination coefficient values of the resistance R and the reactance X, for needle electrodes (R2R=0.9683; R2X =0.9063) and plate electrodes (R2R=0.9442; R2X =0.8347). The Cole-impedance model well represented the collected bioimpedance datasets with standard deviations of 0.9611 Ω for needle electrodes and 0.9272 Ω for plate electrodes. Furthermore, there were significant differences in the Cole-impedance model parameters, which were attributed to the formation of ice crystals that implied cell membrane degeneration during freeze-thawing. Our results highlight the potential of bio-impedance measurements, gaining better insight on quality defects assessing in freeze-thawed meat.