Sunday, March 14, 2010

Deep Science

E-mail forwarded from of friend of mine.

"Nice to see you the other night and thanks for the taste of the Gaja. I thought it was a nice wine, if not memorable. The main issue that I had with it were the rather green and astringent tannins for its overall weight. Some food for thought in guiding your future purchases follows.

With late ripening varieties like Nebbiolo and Cabernet, warm vintages (like 2000 in Piemonte) are problematic. On release they show well. You expect some tannin, they are after all young, and the high glycerin that comes along with high alcohol seems sweet. Sweet enough that the nature of the tannins are not very apparent at that point.

I think that most wine drinkers equate warm years with high levels of ripening, yet often the reverse is true. Ripeness was typically measured in terms of sugar in the grapes, which warm years provide lots of. But a more modern and accurate view looks at the ripening of the phenolics (tannins) which only occurs through lots of photosynthesis from a long "hang time".

Photosynthesis also produces sugar, but high sugar concentrations also occur from the dessication of grapes through evaporation in warm years. So in a warm year in a region that grows a late ripening variety, sugars rise rapidly due more to dessication and the resultant small tight berries (little water in them) more than actual production of sugars through photosynthesis.

The high sugar concentration occurs before the hang time is long enough to create the ripened phenolics, and the grower is in a bind. Pick now or wait? If they pick when the sugar is high enough to achieve 13-14% in the wine, the flavors will be less developed and the tannins on the green side (those kind rarely resolve and integrate into the wine). If they wait until the phenolics show ripeness, the sugar will now be at a level to produce a wine at 18-20%. Also in warm years the high temps create low acid grapes, so the PH will be high and the sugars, off the charts.

You can't make good wine from musts like this. You would then (whether legal in your area or not) have to water back the must to get a 14-15% wine and then add lots of acid that you buy from a chemical lab. Also, by the way, not a formula for great wines, but this "formula" is VERY common in CA.

I have tasted many 1997's from Tuscany, another hot vintage that was highly lauded on release, ( I am thinking about a bottle of 1997 Solaia that *** offered me a taste of recently) that are now, absolutely shot. Most 2000's from Piemonte may go this way very soon too."