Jean Guillaume Prats Interview 2009 Cos d’Estournel, 2010 Cos d’Estournel



Over the holidays, The Wine Cellar Insider sat down with Jean Guillaume Prats of Chateau Cos d’Estournel. At the time, blending trials for the 2010 vintage had just commenced.  We discussed the recent Bordeaux wine vintage in detail.  We also talked about 2009 Cos d’Estournel and the controversy the wine engendered.  Prats is a straight talker. If you ask him a question, be prepared for an articulate, straight up response.

As of today, what are your early thoughts of the 2010 Bordeaux wine harvest for Cos d’Estournel

 “2010 is at the same level of 2009, but in a very different style. It is much more classical and in the line of the vintages produced some 20 years ago. It has fairly low PH with great minerality. Some of the fruity merlots almost have a Pinot noir feeling.”

 As a matter of style, does 2010 remind of you any previous Bordeaux wine vintage? 

 “2010 reminds me of a complex blending of 1959, 1990 and 2005.”

 Stylistically, what do you take from each of those vintages? 

“The fatness of 1959. The balance and freshness of 1990 and the class and ripeness from the Bordeaux wine we produced in 2005.”

October 4 brought a significant amount of much needed rain to St. Estephe and other Left Bank chateaux.  By the time the storm arrived, you were still picking.  Did you reach the levels of phenolic maturity you were seeking?

“We finished harvesting  Saturday October the 9th  like many of our prestigious neighbours in the Medoc. We stopped harvesting Monday the 4th as it does not make sense to harvest under the rain, when the grapes can easily wait. The rain was very positive. It helped speed up the acquisition of phenolic ripeness.”

Did the drought present you with any unique challenges with the 2010 Bordeaux wine harvest? 

“We experienced dry conditions in 2010 that were in some regards, similar to 2003. The Cos’ gravel and clay terroir responds extraordinary well to this phenomenon.”

Thinking back to 2003, what is it about the terroir of Cos d’Estournel that allows you to produce great Bordeaux wine in draught years?

“The fresh clay we have under our profound gravels is of great help to the old vines along with  roots going deep into the soil  (more than 10 m down).”

Will 2010 be a vintage marked by low yields and more Cabernet Sauvignon at Cos d’Estournel? 

“We have two hectoliters per hectare more than last year with an average of 38 hectoliters per hectare. We shall have a similar blending than in 2009 maybe with a bit more new oak and much more acidity.”

How did your gravity flow cellars help you with the 2010 vintage?

“As far as the last two years are concerned, it gives purity and an extraordinary precision in the definition of the tannins. It is a stylistic evolution towards precision in the wine making.”

Can you explain the process of gravity flow and how it works?

“We do not use mechanical pumps. We are only using the flow of gravity to move the wine. We can do this because our vats are on elevators.”

 When will you start blending trials for the 2010 Cos d’Estournel?

“December 21st was our first blending session.”

We spoke several times during the growing season as well as during the vinification period.  Your views on the potential for 2010 at Cos d’Estournel have moved up and down.  Most recently, you said the wine was turning out better than you had originally anticipated.  What has changed in the wine that offered you more hope for 2010?

“Probably in my mind is the fact that our 2009 is so exceptional, I could have been skeptical on the possibility that we could produce another vintage at the same level of quality. It looks like that could be the case. But in a very different style.”

How does 2010 compare with 2003, 2005 or 2009, my three favorite vintages you have produced?

“It is in the style of 2005. But with more weight and a fresher finish.”

What does the combination of high alcohol and low pH mean for a wine stylistically?

 “If you have the two elements above, coupled with a high tannin level, you are likely to have a balanced wine. If not, it could be a wine that will not last or develop a lack of harmony in time.”

Will you make any special choices during the 2010 vinification due to the high alcohol and low pH levels?

“Every vat is different in terms of length of maceration and level of extraction. Therefore it is impossible to give you a general answer. It is one answer to one problem after the other.”

Having tasted your 2009 wine with you on several occasions, I think it is one of the top wines of the vintage. It’s a strong candidate to receive triple digit scores from Robert Parker when he reviews it in bottle.  Not everyone agrees. Your 2009 sparked more controversy than any other wine from the vintage.  Why do you think 2009 Cos d’Estournel is controversial?

 “It is a combination of various factors. I note with satisfaction that even those who did not like it recognize the great work which has been done and the care for details.  A vintage like1945 or 1947 was excessive. Surely the Mouton 1945 and the Cheval Blanc 1947 were also excessive wines when very young. They could have tasted like Cos 2009 and they were considered atypical for their time.  2009 Cos is a wine that set a new style in Bordeaux with the use of gravity.”

Could you explain what you mean when you say “a new style of Bordeaux wine”?

“It’s a new concept to use gravity during “délestage”, bleeding or pumping over. When the fruit is very ripe and therefore more fragile, it gives a fantastic definition to the wine. It is as if the tannins are cut with a laser or a diamond. There is no “organoleptic” imperfection.”

How does the use of gravity impact the wine?

“It adds purity and perfection. The idea is offer the true, honest, most obvious expression of the terroir. This happens because there is no mechanical intervention on the grapes or the fermenting Bordeaux wine.”

I have heard that your father used to say, “50 years ago, even then Cos was said to produce a new style of Bordeaux wine.”  Is that true?

“Yes, it’s true. I recall that during the 70’s when we added a new cellar at the same time as Haut Brion that happened. And at the end of the 80’s when reverse osmosis replaced chaptalization.”

Based on your comment on the 2010 as having “The fatness of 1959, the balance and freshness of 1990 and the class and ripeness of 2005,” I am looking forward to tasting your 2010 Cos d’Estournel with you in April.


  1. Jeff, next time you come to Europe reserve some time for a special German and Austrian Riesling night either in Frankfurt, Berlin or Vienna.

    I share your view on Pavie 09 vs 05, my all time favorite is 00.

    • KP… I’m with you on 00 Pavie. But in a few years, I firmly believe 05 Pavie will give it a run for the money.

      I like all those cites. I had some nice meals in Berlin. I’ll you know the next time I am out that way.

  2. KP… I’m with you on 09 Pontet Canet. For me, it’s the best wine Tesseron has made yet. Pavie was also strong. But I liked 05 Pavie better. It was better balanced with more freshness and acidity.

    You’ll have to talk with Martin about the German wines. I bet they’re great, I never get to taste them.

  3. KP… Thank you for the detailed comment.

    I am a huge fans of the Bordeaux wine being produced at Cos d’Estournel starting with 2003. For me, there is an intense sense of purity, refinement and concentration.

    The wines show great young. I am positive they will evolve into sublime tasting experiences.

    When did you taste the 2009?

    • Jeff, i tasted Cos two times in Bdx last year and was very impressed. I hope that 09 won’t be the one falling from the cliff but it is for me very hard to decide since I am not a very experienced barrel taster like Robert Parker or you. However, from a mere scientific perspective it seems to be a given that sooner or later the Cos vinification gamble will lead to a rapidly disintegrating wine resp. a wine with a lot of dry heat on the palate. But let us see, if there is one winemaker who is the three trick pony of the winemaking world it could be Prats.

      • KP… There is nothing to worry about with 2009 Cos. There’s a lot going on, it’s rich and even decadent, but everything is in perfect balance. Some tasters made comments about 2003 Cos, that wine continues to improve. My money says the same thing about 2009.

        I’m looking forward to seeing how those wines develop over the years.

        • My Bdx favorites besides Cos were Pavie, Tertre Roteboeuf and Pontet Canet. White favorites were Emrich Schönleber Halenberg, Schäfer Fröhlich Felseneck and FX Pichler Unendlich

  4. “If you have the two elements above, coupled with a high tannin level, you are likely to have a balanced wine. If not, it could be a wine that will not last or develop a lack of harmony in time.”

    This quote from Prats really nails it. Although I am a big fan of Cos and have subscribed for the last 7 or 8 vintages, there is a tremendous risk that once in a while a vintage with high tannin levels and high alcohol levels and a ph level that does not match will never integrate. I hope this won’t happen to 09 and I am looking forward to the first tasting of 10. Nevertheless, Cos winemaking is cutting edge winemaking but sooner or later a vintage will fall from the cliff. I hope that Prats will be fair enough to give an early warning.

Post your comments or questions now