Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
Can wine turn poisonous if the process of winemaking is less than perfect—for example, less sugar content and hence less alcohol?
—Dev, Greater Noida West, India
The short answer is no, wine cannot become poisonous. If a person has been sickened by wine, it would only be due to adulteration—something added to the wine, not intrinsically a part of it. On its own, wine can be unpleasant to drink, but it will never make you sick (as long as if you don’t drink too much).
The scenario you describe is actually a desirable style of wine for many who are looking for lighter, less alcoholic wines. But let’s say a winemaker uses grapes that most would consider underripe. You might end up with vegetal flavors, lighter colors, excessive acidity and less concentrated flavors and aromatics. It might also mean a difficult fermentation if the yeast run out of sugar to convert to alcohol. But no poison.
That’s not to say wines don’t have problems—just none of them are toxic to humans. A wine can start to ferment inside the bottle unexpectedly, get exposed to too much oxygen, have a spoilage yeast called brettanomyces, have excess sulfur compounds, contain too much volatile acidity or even be “corky” with the compound 2,4,6-tricholoanisole (TCA). But all of these issues—even if a bottle of wine turns to vinegar—just make a wine unpleasant to drink.