A sterilizer comprising an active oxygen species irradiation unit that irradiates an active oxygen species-containing gas that is a reaction product of a plasma generated using an alternating current and a water-containing gas containing water vapor, at 50 to 300 ° C A sterilizer, further comprising a water vapor supply unit for supplying the heated water-containing gas, wherein the active oxygen species-containing gas contains moisture equal to or greater than a saturated water vapor amount. The sterilization apparatus of the present invention exhibits excellent sterilization activity, and is suitably used for sterilization of food and beverage products such as containers for foods and beverages, caps that seal the mouths of containers, medical instruments, vegetables and meat, etc. It is done.交流電流を用いて発生させたプラズマと、水蒸気を含む含水気体との反応物である活性酸素種含有気体を照射する活性酸素種照射ユニットを含んでなる殺菌装置であって、５０～３００℃に加熱した前記含水気体を供給する水蒸気供給ユニットを更に含み、ここで、前記活性酸素種含有気体が飽和水蒸気量以上の水分を含むことを特徴とする、殺菌装置。本発明の殺菌装置は、優れた殺菌活性を示すものであり、例えば、飲食品の容器、容器の口部を封鎖するキャップ、医療器具、野菜や肉などの飲食品等の殺菌に好適に用いられる。
