The Role of Earth Sciences in Historical American Whiskey Production

Joe T. Elkins, Ph.D. Co-founder/Distiller, Elkins Distilling Co. Associate Professor, Earth and Atmospheric Sciences University of Northern Colorado Map of Breweries in the US (2016) Distilleries in the US (2016) Current Breweries and Distilleries in the US that existed pre-1880

brewery distillery Popular types of American Whisky*

*Whisky: all grain mash, distilled to no higher 80% ABV, bottled to no lower than 40% abv) – Rye (min. 51% rye bill, particularly popular pre- prohibition, early America) – Wheat (min. 51% wheat) – Barley (aka malt whisky, 51% malted barley) • Corn – Bourbon (51-80% corn) – Tennessee ( 80% corn, may use Lincoln County Method) – Corn (80% or more corn) Corn-based whisky

• Corn used as a source of starch, converted to fermentable sugar during mashing • Amylase enzymes are introduced via a malted grain sources (commonly, malted barley, or malted rye) • Low dissolved Fe (iron) content water to aid starch conversion • Sour mashing used to set the pH for mashing and as a source of bacteria for acid->ester production

Current Breweries and Distilleries in the US that existed pre-1880

brewery distillery Observations

• Historically, brewing was constrained to cooler temperatures than distilling • Historically, distilleries making whisky from corn and using sour mashing confined to narrow range of geomorphic provinces in Kentucky and Tennessee Technological innovations that changed the map • Commercial refrigeration (1870’s) • Water treatment – Sand Filtration (1804) – Chlorine ( John Snow, 1854) – Ion Replacement (1903) The Dunedin Effects of Climate Effect of Climate

• Warm temperatures favor bacterial growth over yeast during fermentation – Detrimental to brewing – Beneficial to sour mash whisky making

Current Breweries and Distilleries in the US that existed pre-1880

brewery distillery Average Warmest Six Months

brewery

distillery

Effects of Geology and Hydrogeology Effects of geology and hydrogeology

• Low Fe (iron) water is key to making whiskey from corn • Corn used as a source of starch, converted to fermentable sugar during mashing • Amylase enzymes are denatured in water over 25ppm Fe (Smiley, 1999 and Miller, 2016) Geology of the US Earth, 540 mya Earth, 500 mya Earth, 470 mya Earth, 450 mya Earth, 430 mya Earth, 400 mya Earth, 370 mya Earth, 340 mya Earth, 300 mya Earth, 280 mya Earth, 240 mya Earth, 170 mya Earth, 105 mya Earth, 90 mya Earth, 65 mya Earth, 50 mya Earth, 35 mya Earth, 20 mya Earth, 18 kya Earth, today North America, 485 mya North America, 470 mya North America, 450 mya North America, 345 mya Geology of the US

Geology and Geomorphology of Kentucky Geomorphic Provinces of Kentucky

KY Whisky Distilleries

• The Knobs – First Order Streams – Headwaters of Salt River Watershed – Groundwater-fed surface flow – Ordovician Limestone aquifers: low Fe, high Ca • Inner Bluegrass Region – Groundwater-fed surface flow – Kentucky River and Salt River Water sheds – Ordovician Limestone aquifers: low Fe, high Ca Geology and Geomorphology of Tennessee

Farrar Distillery (1875-1902)

Cascade Hollow Distillery (1877-1910, 1958 present)

Jack Daniel’s Distillery (1866- 1910, 1938-present) Location of Historical Tennessee Whiskey Distilleries within eastern Highland Rim

Aquifers (groundwater)

Geology (rocks) Location of Historical Tennessee Whiskey Distilleries within eastern Highland Rim Overview of Environmental Constraints for Tennessee Whiskey Distilleries Prior to Industrialization

-Located in the hollows of the Dissected Escarpment of the eastern Highland Rim geomorphic province -Situated on First Order Streams -Distilleries had first use of water in watershed -Water sources are groundwater-fed near the contact between Mississippian and Ordovician formation -Water sources are low in Fe, and high in Ca derived from Mississippian and Ordovician aquifers Similarities of KY and TN Whiskey Distilleries • The Knobs and Dissected Escarpment of the Eastern Highland Rim most similar – Topographic context – First Order Streams – Groundwater-fed surface flow – Headwaters – PZ Limestone aquifers: low Fe, high Ca

Future work

• Understanding the nature of Ca in mashing and mellowing/aging – Implication for accelerated mellowing • How the Inner Bluegrass differs from the The Knobs in terms of groundwater chemistry • Why Fe denatures amylase enzymes

• Questions?