Food allergy significantly affects the life-quality for many people worldwide and is life-threatening in extreme cases. In recent years the incidence of this disease shows a gradual increase in many countries. It is a well-established fact that common food-processing operations involving heat treatments fail to significantly decrease the allergenic reactivity of foods. Furthermore, allergenic proteins are remarkably resistant to proteolysis by digestive enzymes and often remain intact after passing through the gastrointestinal tract. The tested materials were protein extracts from sesame seeds, milk and peanuts, or isolated proteins from the same sources. Treatments investigated included application of 6 to 10 pulses of high-frequency acoustic shock waves, lasting a few microseconds. The treated samples were tested in vitro by Western blotting with sera from humans diagnosed to be allergic to the food in question, and in vivo by measuring the IgE levels produced in young Brown Norway rats exposed to the tested proteins by sensitisation through i.p. injection, or by feeding for up to 6 weeks, using direct and indirect ELISA. The treatments markedly decreased or completely eliminated the allergenic reactivity of the foods, as evidenced by the assays used.