Wine is a living entity. This is never so obvious as when you compare a long aged wine with younger wines.
By “living” we don’t mean there are actual critters of some sort involved — that’s usually a bad sign. Wine is made up of a swirl of organic compounds, just like real living creatures. Those compounds do not become static once the cork is put in the bottle.
Phenols and esters are the two classes of naturally occurring compounds chiefly responsible for the aromas and tastes we perceive in our wines. Esters provide many of the fruity aromas. Ethyl butyrate, for example, has an aroma of pineapples, and benzyl acetate is apple-like. Esters react easily with acids and alcohol in a wine. In young wines, these continuing reactions mean that the fruity and floral flavours of the wine change constantly. Over time, the balance of various ester compounds with the alcohol and acidity of the wine will stabilize to yield a steady flavour.
Phenols cover a wider range of flavour affecting compounds. Thymol (found in the herb thyme), eugenol (cloves), guaiacol (smoke), and frambinone (raspberry) are all phenols which can be found in wine — some originating from the grapes, and some from aging in toasted oak barrels. Another important phenol group are the tannins, which come from both grapes and barrels.
Tannins are particularly important in the tasting of aged wines for several reasons, including roles as preservatives and antioxidants. They bind well with proteins (which is one reason big red wines match well with meat) in the saliva in our mouths, so the lubricating properties of the saliva are reduced and our mouths pucker and feel furry. Tannins also bind well with each other, so as wines age they form longer and longer molecular chains, sometimes dropping out of the wine entirely as sediment. These long chain tannins have less capacity to bind with proteins. As a wine ages, the tannins evolve from sharp and gritty to smooth and silky.
The tiny amount of oxygen that penetrates through a cork and into a wine over years or perhaps decades of aging slowly “oxidizes” the wine. A little bit is fine, as it both changes the colour and influences the flavours. The flavours slowly evolve from simply fruity to include earthy, woody and nutty aromatics. Too much oxygen, however, will kill most wines, especially when combined with heat.
Liking old wines is not a requirement for being a wine lover. I have many wine friends who prefer the qualities and fresh bouquet of younger wines. Choose according to your own tastes, but don’t turn down a chance to try an older vintage if you have not done so before!
I was lucky enough recently to be asked to share a Château Leoville-Lascases from 1967. At a mere 47 years old, this wine was brick-red in colour. The aroma was abundant and still showed some fruit to my nose, which I would describe as dry cherry and included some cedar and graphite. The tannins were indeed smooth and silky and contributed to the appreciation of a long finish. This was a lovely treat! I understand bottles from the same case will soon appear at a local charity auction.
Steve Delaney is a member of the Opimian Society. Email him at firstname.lastname@example.org