By Mikayla Keen

While many of you are participating in Dry July our grape scientists are pressing onwards, pouring more science into every drop.

Recently one of our research teams identified the gene responsible for the herbaceous, green, vegetable aromas of wine. Some grape varieties do not produce the compounds (methoxypyrazines) responsible for the aroma. By comparing genetic maps of those grape varieties which do produce the compounds with those that don’t, we were able to pin down the gene responsible.

Dr Paul Boss, who lead the research team, has been sniffing out the complex molecular bouquet of flavour and aroma for the past decade. “We’ve known about methoxypyrazines, the compounds responsible for the green flavours in your Cabernet Sauvignon or Sauvignon Blanc, for years but now we understand what gene is responsible for this character,” Paul said.

Complex molecular bouquets... pouring more science into every drop.

Complex molecular bouquets… pouring more science into every drop.

“There is a growing understanding of the compounds which contribute to aroma and flavour in the finished wine, however, there is little understanding of how compounds in the grape berries contribute to the final flavour and aroma characteristics.”

By identifying these compounds, understanding how they are made and how they make it into wine opens the door to new ways of managing flavour in the vineyard.

“If we can objectively measure grape flavour attributes in the vineyard it would be possible to predict and optimise wine flavour and aroma before the grapes are even harvested, providing a step change in improving our ability to efficiently grow grapes to suit desired wine styles and improve decisions about harvest timing.”

So the next time you’re sipping your Sauvignon Blanc and enjoying those green, herbaceous notes, remember it’s the methoxypyrazines hitting your palate.

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July 15-19 is the Wine Tech Conference in Sydney. Our grape researchers are presenting their work on developing smarter, faster breeding for better disease resistance and controlling berry ripening in the vineyard.

Media: Mikayla Keen   Email: Mikayla.keen@csiro.au   Phone: (02) 9490 8448   Mobile: 0467 788 023