Ultrasonic measurement device for the characterization of microbiological and biochemical processes in liquid media

A measuring device for the characterization of liquid media based on the propagation of ultrasonic waves is presented. It is a four-channel system especially designed for monitoring microbiological and biochemical processes. The liquid samples are placed in commercial glass bottles which can be sterilized. The bottles have inlet and outlet tubes, which can be used for adding substances or extracting samples during the measuring process without interruption. Magnetic stirring can be used to keep the liquid agitated for homogenization purposes. Thermal control elements assure the temperature stability during the measurement. The liquid characterization is based on the detection of amplitude and time-of-flight changes in the sample under study. The main features, operation and performance of this ultrasonic device are analysed in this work, and some measurements and preliminary results are shown.