The invention relates to a method for producing a liquid or semi-liquid product that is sensitive to oxidation, for example beverages, wherein the production method includes a step of deoxygenating an intermediate medium involved in the production of either the liquid or the semi-liquid, and a heating step, for example pasteurization, after the deoxygenation step, characterized in that the method involves injecting a hydrogenated gaseous mixture into the liquid or semi-liquid between the deoxygenation step and the heating step.