I recently tasted a pinot noir from the same bottle over five days. Every day I poured out a bit into a glass, then put the cork back and placed the bottle in my wine cellar at 14 to 16 C. The wine aroma became extremely nice and it tasted best on Day 4. Day 1 was too powerful. Day 2 better. Day 3 the worst. Day 4 the best both on nose and palate. The alcohol content was 14 per cent and the price about €80. Is there anything about the wine quality you can tell from this experience? Too much preservative? Or was this an exceptionally great pinot noir?
It probably means you had a very fine wine on your hands. Great wines tend to be more concentrated and structured for the long haul and can take time to open up to be their best. Some also will go through a so-called dumb phase that temporarily robs them of vitality (at least that's the prevailing wisdom among experts who generally aren't dumb about wine). I suspect your wine's Day 3 corresponded to that phase, which might otherwise have presented itself years hence had the bottle remained sealed.
Given the €80 price tag (about $125 at current exchange rates), I think it's unlikely that preservatives were the reason your pinot lasted well for days after opening. Producers of most superpremium wines eschew preservatives, at least save for tiny amounts of sulphur dioxide, a gas, ubiquitous in the wine industry, that shields the liquid from oxygen damage but which blows off quickly once a bottle is exposed to air.
It's tough, in the end, to make any sort of Day 4 generalization, though. Your experience could have been influenced by any of several factors. There's your own personal taste, of course. Perhaps you enjoy evolved flavours, the sort that hint more at dried fruit, such as prunes and raisins, versus fresh fruit? Perhaps most crucial of all is the fill level. How much airspace was left in the bottle after each pour? Short pours won't seriously disable a wine; in fact, a bit of oxygen exposure over the course of several days indeed could "open up" flavours of a fine wine. But if you're left with just one-third of a bottle by Day 4, you're usually looking at a pretty moribund wine.
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