A new pressure change technology (PICT) for a non-thermal inactivation of microorganisms in liquid food and pharmaceuticals is described. This technology was applied to food-relevant microorganisms and was capable of reducing the organisms up to 7.5 log. The influence of process parameters (type of gas, pressure, and temperature) was investigated with the help of physiological changes of microorganisms. The results of this pressure change technology are shown and discussed.