Electrical Impedance for Easily Discover Undeclared Freeze-Thaw Cycles in Slaughtered Beef Meat

A portable, electrical impedance spectroscopy device to monitor the bioimpedance’s resistive component of beef meat by injecting a sinusoidal current of 1mA at 65.5 kHz was developed. In 4 slaughtered beef both right and left longissimus dorsi muscles where trimmed and left muscle portion was frozen to -18° C up to 7^th day while right one was meantime maintained at 5° C. Median value of specific resistivity of not-frozen sample was about twice Ω cm^-1 with respect of that of frozen-thawed sample (P = 0.004). It was concluded that the device is reliable to monitoring the ripening of beef meat in situ.