The moist heat method consists to submit for a certain time the material to a temperature sufficiently high in presence of water under liquid form. The combination causes the deterioration of the enzymes and proteins of the microorganisms and, by consequence, their death and the destruction of the spores. The effect is a lot faster in comparison to the method known as “dry heat” (asking also temperatures well much higher), because in this case the mechanism of action is based on the slowest oxidization by the air of the essentials of the cells. The autoclaves are the most known devices applying the moist heat method. For a physical law, by increasing the pressure also increases the boiling point of the water that, under pressure, remains under liquid form beyond 100°C. In general, the heating can be made either with electric means or also by injecting saturated steam.