Distillers often incorporate unconventional items when creating new varieties of liquor. And one group of enthusiasts in Michigan is using a 150-year-old secret ingredient in their latest batch of whiskey. Mammoth Distilling in northern Michigan offers, among other spirits, a variety of whiskey products largely made from rye. They source their ingredients from a range of locations, including a special varietal found on South Manitou Island that they procured with a permit...
