Method of determining foreign material in food products using ultrasonic sound

Abstract

A method of determining foreign material such as metal and bone particles in food products, the method using ultrasonic sound frequencies from a plurality of transducers disposed in a rotatable cylinder having a liquid copulant. The cylinder having a surrounding flexible wall which is compressed on top of the surface of the food products. The sound frequencies are transmitted through the food products and received back by a receiver in the transducers for monitoring any variance in the frequency indicating foreign material in the food products.