The Australian Wine Research Institute

Metal ion speciation: Understanding its role in wine development and generating a tool to minimise wine spoilage

Project summary

This project is designed to provide practical tools for winemakers to evaluate the potential of their wines to be impacted by copper and iron, and provide further understanding of the role of metal ions on wine development. The approach taken will be to build on current ‘research-oriented’ tools that measure different forms of metal ions (metal speciation), rather than the traditional approach of measuring total metal ion concentration, and then investigate the ability to relate the speciation measures to metal-induced processes in wine. Also, the components of wine able to interact with metal ions to form inert or ‘non-active’ metal species will be identified.

Speciation measures that provide a good predictor of metal activity (i.e. responsible for specific detrimental wine effects) will be developed into a more routine analytical method suitable for the wine industry. Metal ion speciation studies will provide a tool to enhance winemakers’ knowledge of wine composition and the ability to relate composition to wine stability.

The project will build on CSU expertise in metal speciation studies and metal-catalysed oxidative systems, and complement the work at the AWRI by looking in more depth at why metal ions lead to the formation of volatile sulfur compounds in reductive environments and what wine compounds mediate the actions of metal ions.