Pucker up for some Tannin, Wine and Food

May, 2009

I think one of the most fascinating elements of wine is tannin. I have been lucky enough to taste some great wines in their infancy and they often feature considerable tannin. Tannin that can be quite drying or mouth puckering. Some wines I describe as being so tannic that it sucks the whole room into the glass. 

However in great and good wines this tannin is usually balanced by or in harmony with the other key elements of wine such as fruit, acid, oak, alcohol and sweetness, or likely to be with cellaring. But overt or domineering tannin can be a real put off for many imbibers. 

Generally as wines get older the tannins will soften or become less pronounced, never the less if the other elements are not there in the first place no amount of careful and patient cellaring is going to take away or soften the astringent blows of an over the top tannic wine. 

Tannin is usually evident and desirable in red wines but can be found in whites particularly some examples of chardonnays, where it can be either a positive or a negative. 

So where does the tannin come from? The sources of tannin in wines are the skins of the grapes, the seeds of the grapes, the grape stalks and from oak the wine may have been matured in. 

To make a white wine you harvest grapes and put them through a crusher that splits the skins to help the juice flow. This mixture of grape skins, flesh and juice is then transferred into a press where the juice is run off into a tank to be fermented. Depending upon the producer and the style of wine, the balance is then pressed to extract more juice and perhaps tannin. As the pressure is increased tannin is released from the grape skins, the grape seeds and the grape stalks. Usually the winemaker will run off the initial juice into one tank, the first pressing into another and the further pressings which can be quite astringent into another or indeed they will stop pressing when the juice becomes astringent. Some whites are left on skins for a few hours before pressing to add complexity and some tannin. 

In the case of red wine the grapes are crushed then transferred into a vessel of some sort, such as a tank, open fermenter, rotary fermenter then fermented. As the red must (as crushed grapes are known) begins to ferment colour and tannin begin to leech out of the skins, along with tannin from the skins and stalks. A ferment creates its own heat and the hotter it is the more tannin that will be extracted and the more astringent it is likely to be. This is one of the reasons winemakers try to control the temperature of their ferments. 

Once the red wine has fermented it is pressed, which extracts more tannin, and then usually transferred to oak barrels or oak vessels for oak maturation. In many cases the fermentation is completed after pressing in oak barrels as it is felt that the oak aromas, flavours and tannin are more pronounced but more integrated as a result. 

Oak has natural tannin which is imparted to the wine as it comes into contact. The amount of tannin taken up by the wine is dependent upon the age of the oak, the age of the barrel, the size, the type of oak, the level of toast or char and how long the wine spends in the barrel.  

Why do some wines or types of wine have more tannin than others? It depends upon the grape variety, how ripe the grapes are, the maker, the vineyard site and the season. Some varieties like Tannat, Petit Verdot, Mourvedre and Cabernet Sauvignon seem to have a natural propensity to be tannic. More and more winemakers are aiming for what’s called physiological ripeness in grapes not sugar ripeness, because then the grape pip has softer, fine tannins that are less astringent and harsh. 

Some makers and wine styles strive to extract tannin to provide structure and longevity to the wine. Barolo wines from the Piemonte region in north western Italy, made from the Nebbiolo variety are particularly high in tannin and require to be laid down for years to reach their full potential. 

The region of Cahors in South West France is renown for its tannic wines although there is a measure of restraint being shown these days to suit the market. 

If you look at the assessments of the vintages of Bordeaux, Burgundy and the Rhone, indeed for any wine region, you will see comment on the level of tannin in the wines which varies from year to year, with firm tannins one year, pronounced tannin another and soft or subtle tannin in others. 

I always find one of the interesting variations in the wines from different countries or regions are the nature of the tannins in the wines. Australian wines have very different tannins from French wines. 

Many years ago in the early 90s I was fortunate to be taken by Australian wine producer Greg Trott, owner of Wirra Wirra Vineyards and a true eccentric, to a tasting of various mature vintages of Penfolds Grange and Paul Jaboulet Hermitage La Chapelle. As a callow youth with limited experience of French wines let alone great French wines it was the different tannins in the Hermitage that so entranced me. They were fine, delicate but almost aromatic, like an exquisite tea. The Grange had more pronounced robust tannin but then again everything was turned up in Grange. Never the less, with age, wines from both houses were balanced, complex and a joy to behold. The 1971 Grange is still one of the best wines I have ever tasted. 

The tasting was presented by John Duval, then Penfolds chief winemaker and I think Jacques Jaboulet. Present were quite a few wine writers and members of the wine trade. Astonished as I was by the wines, at the end of the tasting there was a spontaneous outbreak of applause, virtually a standing ovation. Very unusual for a trade tasting. 

Like most things to do with wine, tannin is a matter of personal taste. Some people look for soft wines with little tannin, some like to have a bit of grip. At their best tannins are described as fine, ripe or firm, working in harmony with flavour, fruit, alcohol and oak. However, astringent tannin is rarely deemed attractive. 

Interestingly though many people when they first discover Italian wines can find them too tannic and acidic on their own but when drunk with food the scales drop from their eyes. The slightly drying grippy tannins become less pronounced and work wonderfully well with Italian cuisine.