Bourbon Terroir

[haresfur]

Here's a talk at the Geological Society of America Meeting next week. Move over Pinot! Actually it should be well attended since there will be a Willamette Valley Pinot Noir tasting at the end of the session Not sure I can make it because of my presentation.

2009 Portland GSA Annual Meeting (18-21 October 2009)

Paper No. 270-11

Presentation Time: 4:30 PM-4:45 PM

LIMESTONE WATER AND THE ORIGIN OF BOURBON

FRYAR, Alan E., Earth & Environmental Sciences, University of Kentucky, 101 Slone Building, Lexington, KY 40506-0053, alan.fryar@uky.edu

Bourbon whiskey, which is made from fermented corn mash aged in charred oak barrels, is a uniquely American spirit produced almost exclusively in Kentucky. Exports of bourbon totaled more than $700 million in 2007. Its distinctive taste has traditionally been attributed in part to the “limestone water” used in its production. Given the prevalence of carbonate rocks, corn cultivation, and alcohol consumption throughout much of North America and indeed the world, why did bourbon originate in Kentucky, and what roles has water actually played in its history? Addressing these questions requires a consideration of settlement patterns and practices and the characteristics of water in karst terrains.

European immigrants, in whose cultures alcohol production and consumption were ingrained, began moving beyond the Appalachians in the latter half of the 18th century. Thousands of settlers were drawn to the Bluegrass region of north-central Kentucky, which is marked by fertile residual soils developed on limestone bedrock. Corn was readily cultivated and its distillation provided a high-value product that would not spoil. Consequently, production of whiskey commenced there as early as 1776. Many farms and settlements were located near perennial springs in the Bluegrass region. These springs were valuable not only because of a year-round supply of water, but also because their relatively uniform, cool temperature (~14 to 15 C) facilitated condensation of steam during distillation. Moreover, shallow groundwater and streams in the region typically have dilute, Ca-Mg-bicarbonate-type compositions with circumneutral pH, which limits dissolved Fe and promotes growth of bacteria involved in fermentation.

The production of bourbon became standardized and industrial in the first half of the 19th century. Because of the relatively low yield of springs in the Bluegrass region, most distilleries now rely on treated stream water, but some smaller distilleries still use groundwater. Regardless of the exact source of water, its role in the taste of bourbon combines terroir and craft through the growing of grain, fermentation, and distilling.

2009 Portland GSA Annual Meeting (18-21 October 2009)

General Information for this Meeting

Session No. 270

Terroir—The Relationship of Geology, Soils, Hydrology, and Climate to Wine: A Special Tribute to George Moore

Oregon Convention Center: B113

1:30 PM-5:30 PM, Wednesday, 21 October 2009

Geological Society of America Abstracts with Programs, Vol. 41, No. 7, p. 696

[Dangermonkey]

Let's not forget Michters in Schaeferstown PA _ former distillery made Rye and bourbon. Was also located on another large limestone shelf (actually still is and is up for sale BTW)point is it can be done somewhere else if you have the right geology and water.

[Kent Wang]

Does terroir really matter for any of the grains?

Could you just import the limestone water, or make it yourself by adding calcium and other stuff to distilled water?

[thirtyoneknots]

Does terroir really matter for any of the grains?

Could you just import the limestone water, or make it yourself by adding calcium and other stuff to distilled water?

I'd imagine that any 'terroir' expressed in grain would be negligible compared to the character of the water itself. And given the tremendous amounts of water needed to make distilled spirits, transporting it would likely add prohibitvely to the cost. If you wanted to make whiskey elsewhere why not just let it express its own local character?

[TAPrice]

Does any bourbon maker actually use local grains?

My sense was that distillers were just buying grain on the commodity market.

[thirtyoneknots]

Does any bourbon maker actually use local grains?

My sense was that distillers were just buying grain on the commodity market.

I would expect that that is almost certainly the case. And as I noted above I'd be willing to bet it doesn't matter at any rate anyway.

[haresfur]

Does any bourbon maker actually use local grains?

My sense was that distillers were just buying grain on the commodity market.

I would expect that that is almost certainly the case. And as I noted above I'd be willing to bet it doesn't matter at any rate anyway.

I agree, but the grain was produced more locally when the industry was developing. Not bourbon, but Dry Fly here in Washington State uses "local" ingredients which means mostly wheat for their whiskey. I think there's another year to go before the first batch will be out, though.

The abstract focuses on the water, but my reading is even more that the taste of the water on how the water and the soils affected the settlement patterns and production. Importantly, the steady water temperature springs was important for the condensers.

As was noted above, Kentucky isn't the only whiskey producer. There is limestone terrain (karst) in Pennsylvania. and plenty in Tennessee, Alabama, and Georgia so that can't be the only factor in developing bourbon as a distinct product.

[TAPrice]

I wonder if water plays a greater role in the taste of whiskey now that distillers add more of it to a bottle?