A few weeks ago, a friend from Hong Kong sent me the two ‘mind maps’ for grape varieties shown below.

Click both images in the lightbox to see the grape variety maps by JC Viens.

JC Viens is a wine educator and MW student, and he had developed these with winemaker and blogger Tersina Shieh. There are antecedents for this approach, notably in Michael Broadbent’s seminal Wine Tasting, and in Marnie Old’s very useful Wine: A Tasting Course. De Long’s ‘Wine Grape Varietal Table’ is a wall-chart graphic tackling grape variety profiles in ‘periodic table’ style from the wonderfully inventive Deborah and Steve De Long (www.delongwine.com).

And if you share JC Viens’ dream that the complexity of wine knowledge might be summarised in tabular or graphic form, then check out his own, dauntingly thorough attempts to do this via his ‘study guides’, freely available on his website Grande Passione using the following link: http://grandepassione.com/study-guides/. They are a remarkable achievement.

In the original mail, JC had asked if I thought any of the varieties had been wrongly positioned: he was training hard, and the idea was that these maps would help guide him and others through the challenges of blind tasting.

I found the maps seductive at first, and I began mentally adding a few more varieties – Picpoul and Bourboulenc somewhere under Pinot Blanc on the white map, for example; while on the red map Baga might nudge Mourvèdre, and Poulsard bob about well below Corvina. Shouldn’t Carignan go where Pinotage is, and Pinotage migrate towards Dolcetto and Zinfandel? By then, though, I was beginning to see serious problems.

Some stem from common misunderstandings. JC and Tersina have Shiraz towards the top of the tannic spectrum, for example – but assuming that ‘Shiraz’ principally means Australian Shiraz, this is far from true. Because of depth of colour and general opulence of flavour, tasters often assume that Australian Shiraz must be tannic – but it isn’t, because the Australian palate doesn’t like tannin much, and Australian winemakers and critics prefer fine, ‘powdery’ tannins (the consequence of what Penfold’s Peter Gago calls ‘tannin fining’) to the fatter, grippier, fiercer tannins more typical of long-macerated European reds.

Reputationally, Petit Verdot may well belong where JC has it and that might perhaps be justified in the best vats of Petit Verdot at Pichon-Lalande or Léoville-Poyferré after a hot summer, but every time I taste a named Petit Verdot varietal (from Australia’s Riverland, for example, or Argentina’s Mendoza, or from Quinta da Romaneira in the Douro valley) it is much less tannic than any Piedmontese Nebbiolo and most Xynomavro, too.

On the white map, Torrontés is surely not one of the wine world’s most acidic whites (bring on Assyrtico, huddled inside its Santorini baskets), and I’ve never yet come across a Furmint that would be more aromatic than a Muscat.

The key difficulty with mind maps of this sort is that the character of a variety overwhelmingly depends on two things: where it is grown, and what the ambitions are of the person who is making the wine. Viognier and Gewurztraminer, for example, do indeed tend to be aromatic, low-acid varieties when grown in Condrieu and Alsace, but when grown outside their European heartlands they can often be less aromatic and more acidic because winemakers and local drinkers want all white wines, regardless of starting variety, to be ‘crisp’ and ‘fresh’.

Much Garnacha is low in tannin – but the greatest French locations for Grenache are Châteauneuf, Gigondas and Roussillon, and the variety can be much more tannically prolific and texturally rich in those places than Australian Shiraz ever is. The tannins of Malbec, Merlot and Cabernet Sauvignon vary hugely depending on where they are grown, with anything serious from France’s Atlantic ambit (Bordeaux and Cahors) delivering a far chewier mouthful than anything grown in the Southern Hemisphere (with the possible exception of those Argentine Malbecs made by Bordelais winemakers). The key to spotting Pinot from Burgundy in a blind tasting compared to ambitious Pinot from, say, New Zealand is to look for tannic density.

Ditto for acid levels, with almost all Australian red wines having higher acid levels (again, contrary to popular belief) than serious wines made from similar varieties in Europe. Napa, by contrast, slugs it out in the low-acid vanguard with contemporary Bordeaux from ripe vintages like 2009. I recently blind tasted a set of ambitious Australian Cabernets against Napa equivalents. The results are almost unbelievably different, and that difference reflects winemaking ideals as much as — indeed probably more than — terroir.

Note, though, that I keep having to write ‘ambitious’ or ‘serious’. Inexpensive, high-yielding varietals grown in marginal climates make varietal character still more tenuous, though one would hope that such wines weren’t served in an exam context. There is a fashion for early-picking, too – and in many wines from early picked fruit you will taste the harvesting decision more clearly than the variety (since the articulation of varietal character only arrives with ripeness).

Pity the poor wine student, faced with complexity of this order. I still think mind maps are a useful aid, but I would recommend that every student starts with two blank sheets of A3 paper, and slowly fills each one up for themselves, based on their tasting experiences alone and with a total disregard for any kind of reputational aura. Don’t use the varietal name alone, but always varietal name plus location of origin (which also implies a winemaking culture). The same variety might then appear in five or six different places — but I think that the resulting map would be less likely to get you lost.

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Written by Andrew Jefford