Michter's Original Sour Mash Whiskey was the distillery's most popular product in the 1970s and 1980s. While the name "Sour Mash" comes from the same-named whiskey-making procedure (in which some previously fermented mash is used as a starter for new mash to be fermented, similar to creating sourdough bread), Michter's Original Sour Mash is known for its peculiar flavor. It cannot be classified as a rye or a bourbon due to its unique grain variety. Michter's Original Sour Mash Whiskey made a successful return in 2012 with its introduction into the range, after departing from the market in 1989. Michter's Sour Mash has rapidly become a favorite among whiskey fans, staying faithful to the profile and flavor of its predecessor.