Abstract: Water and meat pieces (P) are pumped through a conduit (100), the walls of which are made of plastic having an acoustic impedance close to that of water. The conduit is immersed in a tank (400) full of water. A shock wave generator 200 (capacitor discharge through electrodes) creates a shock wave in the water. A preferably tubular wave guide directs the shock pulse onto the conduit. The shock wave passes through the conduit without substantial reflection because the impedance of the conduit wall matches the impedance of the water. The shock wave tenderizes and sterilizes the meat. Continual plasma discharges are repeated rapidly enough that all of the meat passing through is treated.