The invention is directed to an apparatus and process for marinating foodstuffs in a short period of time. The apparatus includes a food holding container, a base and a shaft for transmitting ultrasonic mechanical vibrations from a source of ultrasonic vibrations in communication with a base, thereby tenderizing and imparting flavor to the foodstuffs. In addition to the ultrasonic vibrations, the apparatus can include a marinade injection system that injects marinade into the meat prior to being subjected to the ultrasonic vibrations.