PROBLEM TO BE SOLVED: To provide a method for producing a liquid food or drink product suppressing secular deterioration such as the generation of deteriorated odor, a liquid color change and the generation of deposition and precipitation upon preservation, capable of retaining satisfactory flavor and taste, and further capable of reducing energy cost.SOLUTION: There is provided a method for producing a liquid food or drink product obtainable by diluting a raw material liquid containing a wheat extract with a dilution liquid having a viscosity coefficient lower than that of the raw material liquid, comprising: a dilution liquid heating step where the dilution liquid is heated to a temperature higher than the raw material liquid before the mixing with the raw material liquid； the primary heating-dilution step where the dilution liquid is swirled at the inside of the raw material liquid to generate a swirling flow, thus, while heating the raw material liquid with the heat convection of the swirling flow, the raw material liquid is diluted； and the secondary heating-sterilization step where, after the primary heating-dilution step, the mixed liquid of the raw material liquid and the dilution liquid is hot-sterilized with conduction heat. The viscosity coefficient of the mixed liquid in the primary heating-dilution step lies in the range of 0.33 to 490 mPa s.SELECTED DRAWING: None【課題】保存時における、劣化臭の発生、液色変化、沈澱や澱の発生等の経時劣化を抑制し、良好な香味や呈味を保持しうると共に、エネルギーコストも低減しうる液状飲食品の製造方法の提供。【解決手段】麦抽出物を含有する原料液を、前記原料液よりも粘性率が低い希釈液で希釈することで得られる液状飲食品の製造方法であって、前記希釈液を、前記原料液との混合前に前記原料液よりも高温に加熱する希釈液加熱工程と、前記希釈液を前記原料液内で旋回させて旋回流を発生させることにより、前記原料液を前記旋回流の熱対流で加熱しつつ、前記原料液を希釈する一次加熱・希釈工程と、前記一次加熱・希釈工程の後に、前記原料液と希釈液との混合液を伝導熱によって加熱殺菌する二次加熱・殺菌工程とを備える液状飲食品の製造方法。前記一次加熱・希釈工程における混合液の粘性率が０．３３～４９０ｍＰａ・ｓの範囲である前記液状飲食品の製造方法。【選択図】なし
