Making wine with a better finish

The Australian Research Council has funded a 成人大片 project investigating a more efficient method of finishing wines, which could save the Australian wine industry tens of millions of dollars each year.

Professor Kerry Wilkinson in a barrel room

Professor Kerry Wilkinson. Credit: Isaac Freeman.

Led by the University鈥檚 Professor Kerry Wilkinson, the research focuses on the clarification and stabilisation of wines 鈥 the processes that 鈥榝inish鈥 wine to prevent undesirable physical or sensory changes from occurring between bottling and consumption.

Currently additives such as bentonite and activated carbon are used to remove wine constituents such as phenolic compounds responsible for astringency (harshness), bitterness, and browning, or volatile compounds that impart off odours and flavours which arise naturally or from spoilage or contamination and taint.

Fining agents like bentonite, which inevitably contribute to some loss of wine, are often not selective and may affect elements in wine that create the aroma and flavour that consumers enjoy.

鈥淭he use of bentonite and other fining processes can lead to 2鈥10 per cent of wine being lost in the process, costing the Australian wine industry around $100 million each year,鈥 Professor Wilkinson says.

鈥淣ew methods that 鈥榝inish鈥 wines rapidly, with higher recovery rates, and reduced waste and input costs are therefore needed.鈥

Professor Wilkinson鈥檚 project has been awarded $1,141,640 over four years, as part of the ARC鈥檚 Mid-Career Industry Fellowships scheme, to investigate the potential winemaking applications of membrane filtration.

鈥淚鈥檝e been working with VAF Memstar on a range of membrane filtration related applications for some time, from dealcoholisation to smoke taint remediation,鈥 Professor Wilkinson says.

鈥淚t is apparent that membrane filtration offers a viable alternative for several stabilisation and clarification applications, particularly phenolic management. And we鈥檝e made some good progress with protein stabilisation as well,聽but we haven鈥檛 quite solved that one just yet.鈥

When wine passes through membrane filtration, it fractionates, with larger molecules remaining on one side of the membrane and smaller molecules passing through.

Only a small amount of the wine constituents that create negative features in wine pass through the membrane, requiring less treatment with additives like bentonite, reducing the amount of wine lost in the process.

鈥淢embrane filtration can also be used to transform wine made from heavy pressing fractions, which would ordinarily be too phenolic, bitter or astringent to be of commercial use, into wine of significantly improved quality,鈥 Professor Wilkinson says.

鈥淪o, in this way, the technology can improve production volume and value 鈥 again, without the use of additives.鈥

VAF Memstar, a South Australian beverage filtration company, is a partner in this project, as is the Australian Wine Research Institute and Hill-Smith Family Estates, owner of iconic Barossan winery, Yalumba.

鈥淵alumba has a very strong commitment to decreased use of additives, so this project aligns strongly with their sustainability goals, and they will support the project through access to wine,鈥 Professor Wilkinson says.

鈥淰AF Memstar will contribute the membrane technology and expertise in wine fractionation needed for this research, and Dr Keren Bindon from the Australian Wine Research Institute will provide complimentary expertise in wine analysis.

鈥淭he industry partners involved in this project are absolutely critical, the research simply wouldn鈥檛 be possible without them, so I鈥檓 grateful for the opportunity to continue our collaboration.鈥

Tagged in featured story, ARC Mid-career Fellowship, Wine research