Friday, August 20, 2010

saignee, spinning cones and terroirists

Militant French winemaker group CRAV are known to detonate explosives and commit arson in protest against legislative changes that threaten their livelihoods while terroirists – their virtual namesakes - are also known to get pretty puffed up about how their particular patch of soil, topography and climate influence their wine quality and style.

Taking the former view is perhaps understandable after a government workgroup proposed new laws that places alcohol on the same level as pornography, and would effectively ban wine on the internet in France.

Technology is also causing tension for terroirists who argue that traditional methods like drawing off of grape juice before on-skin fermentation of red wine (saignee), working the skins vigorously for greater extract (pigeage) and chaptalisation - the addition of sugar, often legal in the old world but illegal in the new - are de rigeur methods of increasing intensity and richness.

However a closer look at these now apparently low-tech methods reveal that modern technology is achieving similar if not better results doing essentially the same thing – manipulating concentrations of various elements but without the low-cost benefit of traditional methods. And, wanted or not, you also end up with a Rosé wine in your range.

The new technologies include spinning cones (SC), reverse osmosis (RO) filtration, and precision (satellite) viticulture (PV). Spinning cones separate the different volatile fractions from the wine by means of centrifugal force and vacuum which are re-blended once alcohol is removed.
Spinning Cone Technology

The EU now permits must concentrators to be used to lower volumes by up to 20% and increase alcohol by up to 2% - or even 3,5% in some areas. However, you cannot chaptalise and concentrate the same batch, even if you know American über critic Robert Parker is coming to town. Bordeaux specialist James Lawther MW estimates at least 60 RO machines operate in Bordeaux while their use is also known in Burgundy, Baden, Piedmont, Tuscany, and South Africa.

Californian agents estimate that as many as 500 US wineries use these technologies -particularly the high end wineries that consistently get tannin maturity and balance. It is also not uncommon to find a nerd herd of PhDs working in their analytical or even R&D laboratories. The standing joke among these winemakers is that MO (micro oxidation, used with in-tank oaking to mimic barrel maturation) can cause spoilage yeasts like Brett (anomyces) but RO can take it away!

RO mimics kidney blood capillaries by directing the flow across rather than through the filter and selected compounds - under pressure in case of RO - will pass through the membrane depending on which is fitted, also known as cross flow filters. Their uses include removing water, alcohol, volatile acidity and volatile phenols – cork dork speak for potentially stinky Brett metabolites.

Now Brett is one chap who often emerges when discussing terroir. While there is evidence to suggest that low levels of some of the flavours – sweaty saddle for example – enhance complexity, terroirists argue this is a function of terroir and improves red wine complexity.

Meanwhile Scientists in Oregon are challenging the notion that terroir can be detected in a wine. As part of a study into vineyard soils, geologists meeting in Portland for last year's Geological Society of America conference concluded that the French ‘gout de terroir’ - translated literally as 'taste of the soil' – probably isn't caused by minerals found in the vineyard.

'If wine lovers are going to talk about a mineral taste in wine, they should acknowledge that we don't at present know its cause”, says geologist Alex Maltman.

And they say the concentration of minerals in wine is below the threshold of human taste and smell. "I am not saying that chemistry and geology have no effect on the wine. It may have effects that we don't understand. But whatever 'minerality' in wine is, it is not the taste of vineyard minerals," said Maltman

Although nobody has been able to objectively show the links between the soil mineral composition and the flavours or fragrance of wines (excluding Randall Graham’s experiment of putting rocks in the tank at California’s Bonny Doon), the most important effect of soil is through its physical properties, or more specifically through the water supply and drainage.

Good drainage, steady supply of water plus restrictive mineral vine nutrition ensures restrained growth resulting in smaller leaves, good berry exposure to sunlight and smaller berries.

While economists and statisticians are regarded with some scepticism for interpreting data for a pre-determined result, a report last year in The Economic Journal found that terroir plays no part in the production of great wines. Two European academics – including a Frenchman whose whereabouts is now probably in question – collected data on environmental conditions and wine making techniques across the vineyards of Haut-Medoc, a classic example for terroirists, and concluded that wine making technologies, not terroir, determine the quality of wine.

The French claim that there is no good substitute for terroir looks at best highly exaggerated the professors said, at worst, terroir has no influence and the right combination of weather, vines, technology and chemistry are sufficient.

Viticulturalists have found that sugar accumulation and acid respiration are indeed climate dependent. Sugar (old world) and acid (new world) additions are among the most common wine making practices. Colour, aroma synthesis and tannin evolution occur more or less the same rate wherever the grapes are grown. All flavour compounds are synthesized in the vine, made from organic molecules derived from photosynthesis and inorganic ions taken from the soil.

But terroir underlines and defines the French Appellation Contrôlée (AOC) system and French producers try to mitigate the numerous drawbacks of this system in order to recover their lost markets as they are now much too strict only recently allowing the use of oak chips for example. Many exceptional wines don’t obtain AOC status because their vines do not conform to AOC rules.

As a result, producers are forced to sell their wine as ‘vin de pays’ a low grade for a wine, while the late Didier Daguenau - renowned pub brawler, world dog sled champion and outstanding Pouilly-Fumé producer - obtained an AOC label for his worst production, a lemon he called ‘quintessence of my balls’, produced with bad quality grapes that are however in conformity with the AOC tradition.

Bordeaux has been preaching about its superior soils for decades, but its wines are changing dramatically as global warming and better viticulture start playing a role.
Some successful winemakers argue that soil is not as important as climate and viticultural management.

However, like most aspects of life, the impact of technology is unavoidable and although great strides have been made, scientists agree that much remains to be understood in viticulture and wine making.

Proprietors have a vested interest in talking up their terroir rather than their winemakers. Winemakers can up and leave, terroir cant. Old world terroirists often aim to make wines that express the typicity of the vineyard site whereas in the new world its understanding the terroir that drives quality.

*Regional Committee for Viticultural Action

Jonathan Snashall

For winemaker-led tours of the Cape


                                                                   Reverse Osmosis Plant

Reverse Osmosis Plant

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