Bill Waters may have solved a mystery that’s “baffled generations of sweet-toothed Americans,” said Guy Adams in Britain’s The Independent. Waters, a rare-manuscripts collector, found what appears to be an early handwritten recipe for Dr Pepper, in a battered ledger in a Shamrock, Texas, antique store. The yellowing recipe for “D Peppers Pepsin Bitter,” calling for mandrake root and other odd ingredients, goes up for auction next week.

The claims that this is an early Dr Pepper recipe are “all wet,” said Dr Pepper Snapple Group in an open letter via PR Newswire. Dr Pepper’s 23 ingredients are a secret known only to three company employees, and you’ll be “‘bitterly’ disappointed” if you expect “wahoo bark, bitter orange peel, and mandrake root” to yield anything like Dr Pepper.

Neither Waters nor the auction house has actually tried to “mix up a batch,” said the AP’s Jamie Stengle in Yahoo! Finance. But even without a taste test, Waters’ $200 find will still probably fetch between $50,000 and $70,000. Even Dr Pepper agrees that the recipe is authentic—the question is, what does it make?