Aroma Masterclass by Michael Palij MW and Dr Rachel Quarrell
Thursday 3rd February 2005, Wolfson College, Oxford
Just how does a simple, juicy bunch of grapes turn into the complex and aromatic beast that we all know and love? Oxford-based Master of Wine, Michael Palij and Dr Rachel Quarrell, organic chemist and a tutor at Balliol and Lincoln Colleges, Oxford, explored the chemistry of wine aromas in a thought-provoking seminar.
The chemistry of wine flavour is complex and not entirely understood. The main components of wine can be listed as water (80%), alcohol, sugars, organic acids, phenols, polyphenols (20%) and “other”. This Masterclass detected and explained "the missing 1%", the trace amounts of hundreds of flavour molecules that give rise to such intriguing - and frustrating - diversity.
Many of the complex organic molecules which give wines their flavours and aromas - including cinnamaldehyde, piperonal, linanol and geraniol – can be made in the laboratory. We compared the aroma of these pure compounds with the ‘real thing’ and then considered the factors that influence their production. As flavours are derived not only from the primary grape constituents but also from those formed during the primary alcoholic fermentation, secondary bacterial fermentations and from subsequent maturation, all of these factors were explored.
It was in every way a sensational experience!
The following table is a summary of the wines and the volatile compounds found to be associated with them. No tasting notes on the wines themselves were made as this was not the object of the session.
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Wine |
Associated volatile compounds |
Tasting notes/presence of volatile compounds |
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2003 Fattorie Morantico, Verdicchio dei Castelli di Jesi, Italy, 12.5%, RRP £3.99 |
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These first two wines were used to locate the structural components of the wines on the tongue. |
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2003 Fattorie Morantico, Sangiovese ‘Borgiano’, Marche, Italy, 12%, RRP £3.99 |
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2003 Goldwater, Sauvignon Blanc ‘New Dog’, Marlborough, New Zealand, 13.5%, RRP £9.99 |
Anisaldehyde |
Clinical |
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2000 Rolleston Vale, Reserve Chardonnay, SE Australia, 12%, RRP £4.99 |
Isoamyl acetate |
Uric acid – stables |
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2003 Bouchard Pere, Fleurie AC, France, 13.5%, RRP £8.99 |
Benzaldehyde |
Marzipan – almonds |
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2003 Errazuriz, Cabernet Sauvignon, Aconcagua, Chile, 14%, RRP £5.99 |
Vanillin |
Vanilla/incense |
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NV Gonzalez Byass, Fino ‘Tio Pepe’, Jerez DO, Spain, 15%, RRP £8.49 |
Acetaldehyde |
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√ |
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NV Emilio Lustau, Moscatel de Chipiona, Jerez DO, Spain, 15%, RRP £4.99 |
Geraniol |
Geramiums |
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Wine Faults |
Acetic acid |
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Courses for wine enthusiasts who wish to develop their wine tasting skills in a friendly, informal setting. To Educate and Inspire.
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To contact WineMatters, please e-mail Dr Karen Hyde, AIWS or telephone 07855-026734
For Diploma related enquiries please contact Mr Michael Palij, Master of Wine or telephone 01993-848777