| Changes of bio-impedance and level of hydroxide- praline ,pH,Ca2+ ,total free amino acid of muscle (stored at 1～-1℃) collected from 30 heads of cattle after slaughtering have been studied . The results showed that the higher frequency of initial curent, the lower impedance of the meat sample. Impedances of the sample were increasing at the first 3-day after slaughtering, then lowering steadily after that. Polarization coefficient( K ) changed slightly around third day and the tangent of angle of electric losses(tgδ) were also increasing at the first 3days,and decreasing after then ,the changes were showed significantly(p<0.05).Characteristic frequencies(fc) were increasing during 1～10 days storage time and were ranging from 10 KHz to 200KHz. The track sites of impedance were located mostly in the left side of Cole-Cole plot in early days, then moved to the right side of the plot. Muscle impedance of transverse direction was greater than longitudinal direction.which were remarkble when frequency ranged from 5KHz to 100KHz, but not from 100KHz to 200KHz. Bio-impedances were negatively correlated with pH at first 3 days(p<0.01), were not correlated with the change of hydroxide- praline. The impedance were negatively correlated with the concentration of Ca2+ and free amino acid level of muscle(p<0.05).
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