A great bottle of Old Crow Sour Mash bourbon from the olden days. The 6-year-old Old Crow Sour Mash was bottled in the 1970s at 86 proof. The Old Crow brand is named after James Crow, the Scottish doctor who is credited with having invented the sour mash process. This claim is rather weak, as there is no historical evidence for it. James Crow did use scientific techniques to improve the distillation process, and he likely refined the use of sour mash. Either way, his talents greatly influenced the bourbon we drink today.