Abstract: A meat carcass is inspected ultrasonically to determine its fat-to-lean ratio and to obtain a three-dimensional computer image of the interior of the carcass showing the location, shape and nature of the various pixels of different materials, (fat, lean, and possibly also bone, abscesses or other tissues) in the carcass. These results are achieved by passing ultrasonic pulses into and through the carcass, measuring the timing of both transmitted pulses and return pulses that are reflected from the carcass surfaces and from successive planes between the internal pixels, and measuring the relative intensities of the reflected pulses, the latter measurement providing data on the attenuation coefficients of the various pixels from which their nature can be determined. The velocities of the ultrasonic pulses in the different materials being known, as well as their attenuation coefficients, a computer can calculate the fat-to-lean ratio and can construct the desired three-dimensional image.