Why are some wines not suitable for vegans?
It all depends on how far down the rabbit hole you want to go. Wine is made from grapes, which as far as I’ve seen are pretty much raised free-range. The trouble for vegans is that while the main components in a wine are vegetarian-approved, certain winery practices employ animal by-products that, while not changing a wine’s flavour, may leave traces in the juice.
Now I’m not talking about winemakers stirring their vats with a grizzly bear’s paw; these by-products are used in a process called fining that eliminates annoying sediment from a wine before bottling. Winemakers found that organic compounds such as casein (found in milk), egg whites and isinglass (extracted from a fish’s dried bladder) were able to attract the proteins and other solids that make up sediment while taming aggressive tannins in red wines. Though some wineries use modern, non-organic alternatives, most stick with the tried-and-true old-school methods.
What’s often overlooked by vegans is what happens in the vineyard. Whether manure being used for fertilizer, dead rodent remains joining the soil composition or bug parts getting mashed in with the grapes, if that sort of thing gets your vegan goat, then your wine glass may have to stay empty.