Non-destructive food-sterility and package-quality testing of aseptically packed food products by impedance measurements

摘要

An impedance method for simultaneous non-destructive package-quality and food-sterility testing of aseptically packed food products is presented. The method is intended for 100% on-line testing of TBA (Tetra Brik Aseptic) food containers.An electric model has been developed for the measured impedance. A relation is derived between the resistive component of the measured impedance and the conductivity of the food. The impact of local disintegration of the inner thermoplastic layer of thepackaging material (local leakage) on the measurement impedance is analyzed.The experimental results prove the rapidity and the sensitivity of the method. They also show that we can even roughly determine the size of the leakage area and the distance between its location and a reference point.