PROBLEM TO BE SOLVED: To favorably retain a color tone or freshness of fresh fish and shellfish for a constant time.SOLUTION: A method for producing highly-concentrated oxygen treated water includes steps of: supplying pure oxygen gas for supplying pure oxygen gas to treated water under 1 atm and producing highly-concentrated oxygen treated water for producing highly-concentrated oxygen treated water by increasing the amount of dissolved oxygen of the treated water within a range from three times or more of the solubility to the treated water of aeration dissolved oxygen when setting as oxygen partial pressure 0.21 under 1 pressure of total pressure to less than the solubility to the treated water of the pure acid gas under 1 atm by supplying the pure oxygen gas in the pure oxygen gas supply step.COPYRIGHT: (C)2013,JPO&INPIT【課題】生鮮魚介類の色調や鮮度を一定時間良好に保持させること。【解決手段】1気圧下の処理水に純酸素ガスを供給する純酸素ガス供給工程と、純酸素ガス供給工程において純酸素ガスを供給することで、処理水の溶存酸素量を、全圧1気圧のもとで酸素分圧0.21気圧であるとしたときの空気飽和溶存酸素の処理水への溶解度の3倍以上で、1気圧における純酸素ガスの処理水への溶解度以下の範囲内で増大させて高濃度酸素処理水を生成する高濃度酸素処理水生成工程と、を有する。【選択図】図1
