Goosegogs wrote:
Dunc...why does unoaked riesling age well and sb so badly. They are both pungent grapes with high acidity yet riesling ages so well and sb turns vegetal after about three years ( if that )
Since you ask G, I only know these details by default - I don't know the chemistry, and Mel is the one to give a Master's answer.
By default:
It would appear from drinking experience by those who have cellared or have bought the finest wines, that the Rieslings that live the longest are those wines made from very old vines grown on unirrigated steep vineyards on certain German and Alsace shale slopes. The vines will have been picked late and would have struggled at the end of the season, so that the fruit is very high in sucrose, dehydrated and the skins are worn and weather beaten. Noble rot and the associated fungi aid the longevity anti-aging process (Sauternes & Niagra falls ice wines), and there is another compound that produces the petroly aroma, a carotenoid, a catalist ? that comes from the acid and other elements and compounds naturally occuring in the resultant wine, that would also appear to aid bottle age. Does the carotenoid work like an antioxidant ? Dunno
Mel will know the chemistry. I looked up the petrolly / carot...... business, to see if it would reveal another reason for aging potential in the dry /semi dry styles.
Enjoy, I'm just finishing a '05 St Emilion

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