Sterilization of Large Volume Solution by Autoclaving

Temperature of large volume liquid in respective containers (1-3l) was continuously measured with thermocouple under autoclaving in order to determine the time for the temperature of the liquid to reach 115°. Sterilization temperature, regardless of a number of containers per load, was uniform even at various locations of the containers in the chamber. In spite of rapid rising and lowering of temperature, exhausting time was so long that the ingredients were decomposed. The size of containers was the most important factor in raising liquid temperature to 115°; 40 min for the 3l container. The degree of sterilization was estimated from Log Inactivating Factor (LIF) based on a first-order reaction and the course of temperature under autoclaving. LIF was very useful for the determination of sterilization time, because it considerably agreed with a number of surviving B. stearothermophilus. The sterilization time of the 3l container was thus determined at 60 min corresponding to LIF 11.