[taurknaut]

Pectin breaks down into methanol. Particularly fruit wines and liqueurs will end up with hyper-concentrated methanol. Water will help but cannot remove the pain of actually passing that methanol.

Granted, it's not so bad with the first glass. But with three, be prepared for a nasty hangover. At least this is my experience with applejack. Professionally-made apple jack may be cleaned up more (I kind of hope it is).