I was away at a conference last week. One of those great small conferences where you can spend a lot of time interacting with people outside of the talks. It was great. I'm convinced the best science is discussed over beer and wine. I titled this blog post Wine and Chemistry because I like wine. It's not that I don't like beer. I do. I just can't drink very much of it before I feel bloated and uncomfortable. Thus I much prefer a nice red wine to drink while pondering the deeper aspects of asymmetric catalysis. I am not alone in this. Some friends of mine who were also at the conference are wine lovers and we had a nice little private wine tasting one evening. It was a wonderful experience as I got to taste a wine that was over 40 years old. The cork you see above is from that special bottle of Rioja. Although it was delicate and it broke when we pulled it from the bottle, it was in surprisingly good shape. The wine, on the other hand, was about 20 years past its prime. Not spoiled but it definitely was flat. It tasted like compost. That brings me to a little bit of chemistry. The wine was definitely oxidized but was not vinegar. It was stored well and the closure held up against the ravages of time. It was almost sherry like. Of course the one thing that distinguishes an oxidized wine like sherry is the presence of acetaldehyde. This had quite a bit of it. The tannins were completely gone. I wonder if there was any resveratrol left? Definitely not a wine I would pop and pour at a picnic but it was truly an experience to taste history.
2 comments:
I love wine also. I would make wine at home also, but I have decided to stick with one fermentable beverage for the time being.
Interesting about the tannins. I didn't realize the tannins could degrade like that. But then, I've never tasted a wine that old before.
Oxidized tannns turn into polymers and crash out. The same goes for the anthocyanins - Old reds have a rotten color and there is lots of sediment so they have to be strained. I was drinking the decades-old stuff only handful times and I found them ...strange.
Some clarets that are harsh when young improve with age. But many wines do not. There is an astounding amount of snobbery in wine business; I would rather purchase a really old bottle of booze than wine.
Chemgeek: there is one thing you can do at home: Walnut snapps! It requires whole green unripe walnuts (harvested in early May, with skin, shell and all), plenty of 100+ proof alcohol (or strong brandy, bourbon, etc) and some sugar, and several months of maceration of the cut soft walnuts in jars exposed to sunlight (to bring about the photooxidation of tanins). It takes time but the results are exquisite.
Post a Comment