If you have actually ever discovered a bottle of red wine that's been sitting in your cooking area for a couple of months (or years) and taken a smell, you understand that red wine can spoil. While red wine does not technically spoil the way other food does, exposure to sunshine, heat, and oxygen can trigger it to deteriorate, offering it an unpleasant taste.
How does white wine ruin? Gradually, the substances in wine that provide it its signature taste and scent break down, and the red wine begins to taste vinegar-y and flat. This procedure is speeded up by heat and light, so it's crucial to save red wine in a cool, dark location.
Surprisingly, wine really improves with age, as much as a point. As white wine ages, the tannins (compounds that provide it a bitter flavor) start to break down and the red wine becomes smoother and more complicated. This is why many red wines improve with age and why most gewurztraminers are best consumed young.
Once a red wine starts to ruin, there's no going back. When those tannins have broken down, they're chosen good. https://creaturesincrisis.org/?p=654 If you come across an old bottle of white wine that's beginning to turn, it's finest to just put it down the drain.