Microoxygenation of red wines

Abstract

Microoxygenation is usually applied to red wines as a cheaper alternative to oak ageing. Utilization of wood cooperage for wine storage has several advantages. Among these are extractions of flavour and aroma active components, as well as controlled oxidative polymerization, a process commonly referred to as ageing. Although stainless steel tanks are, in the long term, less costly than cooperage, stored wines do not benefit from the features offered by wood. The process of microoxygenation in steel tanks utilizes controlled exposure of wines to oxygen provided by a sparger linked via a flow meter to a cylinder of oxygen. Oxygen flow rates vary over the course of treatment. During this period, different chemical reactions take place. For example, wine phenols (tannin precursors and anthocyanins) react to form polymeric species that enhance palate structure and colour stability in the wine. Oxygen also diminishes excessively green, herbaceous characters and reductive aroma of wine.