Rotundone: Spice It Up

With some wines, you could be forgiven for thinking someone had sneakily ground some pepper into your glass. But there’s very good reason for it, says Matt Walls...

- Matt Walls

WHAT’S YOUR FAVOURITE smell? For some it’s newly mown grass; for others, sizzling bacon. For me, it’s freshly ground black pepper. I still remember the first time someone drew my attention to its aroma in a glass of Rhône syrah; since then I’ve been insatiable. But it’s not just that syrah occasionally smells like black pepper – syrah grapes contain the exact same flavour compound that you find in peppercorns, and it survives the fermentation process to end up in your glass. It’s a chemical called rotundone and its fascinating properties have only recently come to light. In the late 1990s, the trend in Australian Shiraz started to move from a bold, powerful style to a more elegant, spicy one. Winemakers began asking the Australian Wine Research institute (AWRi) how they might accentuate the spicy element in their wines. In 1999 AWRi decided to investigate, but it took them until 2005 to identify the source of this peppery aroma. ‘it was quite a significant moment in terms of flavour chemistry,’ says Con Simos at AWRi. ‘We let our researchers have a bit of Champagne,’ he adds with a wry smile.

David Jeffery at AWRi observes that the discovery was down to ‘a combination of staff dedication, advanced instrumental techniques, serendipity, synthetic capability and collaboration’. His report refers to ‘gas chromatography-mass spectrometry olfactometry’ – ‘a technical way of saying that compounds in grape and wine samples were separated on an instrument and sniffed.’