Title says it all. Made medlar vodka, followed a googled recipe, opened it the other day to have a smell, and it has a slight fizz to it. So, have I created Medlar champagne, or has it gone bad and will make a good drain cleaner? I did have a little sip, and it tasted fine by the way, and I am still here to tell the tale. The kilner was sterile and the voddy brand new.