review on understanding oxygen mass transfer in wine: influences, measurement methods, and implications

The concentration of dissolved oxygen in wine is a critical parameter that must be controlled during the winemaking process to preserve quality post-packaging. However, oxygen uptake occurs at multiple stages, including production, stabilisation, and packaging. Conventional oxygen removal methods, such as boiling at atmospheric pressure and membrane contactors, are either detrimental to wine quality or cost-prohibitive. Consequently, sparging with an inert gas using a bubble column or an in-line sparger remains the primary approach for oxygen removal. While previous research has focused mainly on oxygen absorption, insights into desorption can be obtained from studies on gas–liquid mass transfer in wine and model solutions. Oxygen desorption is quantified by the volumetric mass transfer coefficient (𝑘𝐿𝑎), which is influenced by factors such as viscosity, dissolved carbon dioxide, concentrations of ethanol, phenolic compounds (mainly in red wines), acids, and surfactants. Herein, we provide a comprehensive analysis of how variations in these parameters affect 𝑘𝐿𝑎. Additionally, the effects of hydrodynamics, design parameters, and operating conditions on 𝑘𝐿𝑎 are investigated and presented in this comprehensive review.