bourbon aging in 7,000 white-oak barrels at the A. Smith Bowman Distillery in Fredericksburg
Source: Thomas Cizauskas, A. Smith Bowman Distillery (November 8, 2014)
bourbon aging in 7,000 white-oak barrels at the A. Smith Bowman Distillery in Fredericksburg
Source: Thomas Cizauskas, A. Smith Bowman Distillery (November 8, 2014)
The Virginia Alcoholic Beverage Control Authority calls bourbon "America's Native Spirit." Europeans were distilling various grains before 1492, but were unaware of corn until they discovered Native Americans growing maize.
People living in the Andes had been making chicha for thousands of years by chewing kernels of corn and parts of other plants and spitting the material from their mouths into a pot with water, followed by heating over a fire. Enzymes in the saliva broke up the carbohydrate starch molecules and exposed sugars, which wild yeasts could then ferment to produce a low-alcohol equivalent to "small beer" brewed by the first English colonists in Virginia.1
In what became Virginia, Native Americans did not produce alcohol. They created an altered mind state through other techniques including sleep deprivation, drumming, pain, fasting, and the "black drink" made from the caffeine in leaves of the yaupon holly (Ilex vomitoria).2
The English colonists brought their traditions with them, but growing large fields of rye or barley for making whiskey was difficult in Virginia. Corn was widely available and Rev. George Thorpe, who managed the land and indentured servants at the College at Henricus, created the first batch of whiskey using corn in 1620. The word "whiskey" was derived from the Gaelic term for "water of life" - uisgebeatha (whiskybae).
The corn-based liquor was distilled at what is now at Berkeley Plantation. After Rev. Thorpe was killed in the 1622 uprising, his estate included an old copper still. On December 19, 1620, before his death, he wrote about starting to distill corn:3
Cider and beer could be produced from local ingredients in colonial Virginia. Efforts to make wine from local grapes were unsuccessful, but wine was imported from Europe. For distilled spirits, Virginia colonists drank primarily peach and apple brandies and rum (often mixed with other ingredients) prior to the American Revolution. Rum was imported from Barbados and other Caribbean islands.
Efforts by New England distillers to import molasses from French colonies and make rum were frustrated by the Navigation Acts in the 1650's and the 1733 Molasses Act, spurring smuggling. Access from English colonies in the Caribbean was restricted more successfully after the American Revolution, but American drinkers switched to whiskey in part because rum was associated with Great Britain.
Rye was the preferred grain; it was more productive than barley in the Mid-Atlantic latitudes. At the urging of his overseer, former President George Washington began distilling his rye and corn, plus grain he purchased, into whiskey in 1798.
When he died one year later, Washington owned one of the largest distillery operations in the United States. His rye whiskey - not bourbon - is the official "state spirit" of Virginia.4
The whiskey produced by Rev. George Thorpe and George Washington was not bourbon. To earn that title, distilled spirits must be aged in white oak barrels which have been charred inside by fire, and at least 51% of the grain used in the distilling must be corn.
Rev. Elijah Craig is often cited as the first distiller to store whiskey in charred white oak barrels. He may have used barrels affected by an accidental fire, or barrels that had previously been used to transport sugar.
He was a Baptist minister born in Orange County, and who relocated to Fayette County in 1782. He is also known as the founder of the town of Georgetown there, in what became Scott County in 1792.
Craig was wealthy enough to have enslaved people make the bourbon, and the distillery producing Elijah Craig has begun research their history as well. Heaven Hill Distillery markets premium bourbons under the Elijah Craig trademark, and ensures he is well known as the "father of bourbon."
However, Craig and his enslaved workers were not the only distillers in the area. Several others had migrated from western Pennsylvania down the Ohio River, moving away from the region which triggered the Whiskey Rebellion. Daniel Shawhan Jr. may have been the first to choose to use charred white oak barrels, creating the distinctive taste of bourbon.5
Today bourbon must be aged for at least two years in the charred white oak barrel. The ageing process is designed to flavor the bourbon, and is both complex science and art. Barrels made from white oak trees harvested in Missouri and Arkansas create a different taste than barrels made from French oak trees. The staves used to make a barrel can be exposed to the air for different lengths of time, and ultimately steamed in different ways in order to be formed into a barrel. Different processes produce different aromatic compounds in the wood.
Temperature management while distillate is in the barrel is a key part of the ageing process. In the Bardstown Kentucky area, now the center of bourbon distilling, barrels are stored in massive rickhouses seven stories high. Rickhouses are not temperature controlled, on purpose. Distilleries intend for the distillate (future bourbon) to expand into the oak when temperatures are hot, and to retreat back into the barrel when temperatures cool. The 53-gallon barrels are moved among the different levels during the aging process to control how the oak and bourbon interact.
At the start of the ageing process, distillate penetrates the inner charred layer. Carbon in the charred wood sequesters sulfur and other molecules that might taint the smooth flavor of the final product. The depth of the charring can vary between different brands.
Adjacent to the charred layer, wood in the barrel was thermal degraded by the heat when the inside of the barrel was briefly burned for 15-45 seconds. The distillate penetrates that layer and interacts with the cell wall polysaccharides (cellulose and hemicellulose) and monosaccharides (xylose and glucose) or "wood sugars," plus the lignin in the oak.
Distillers create different tasting bourbons in large part by managing the diffusion of the sweet polysaccharides into the distillate. Oak staves which have been toasted in different ways may be inserted into a barrel for weeks or months in order to impart a specific taste.
The longer the time in the barrel, the greater the impact of the interaction between wood and distillate. Ageing can be too long, however, creating "wood water" with too strong of an oak-related taste.6
rickhouse under construction near Bardstown, Kentucky
Barrels for aging bourbon are made from just white oak trees. Today 75% of white oaks are mature trees; natural regeneration may not be sufficient to sustain the population and provide a steady flow of barrel staves.
Fear of a future shortage led a pair of US Senators from Virginia and Kentucky to introduce the White Oak Resilience Act of 2025. The bill called for establishing a White Oak Restoration Initiative Coalition to share information and organize research regarding the health, resiliency, and natural regeneration of white oak trees:7
American Bourbon/Tennessee Whiskey sales by volume (2002-2019)
Source: Distilled Spirits Council, On America’s Whiskey Trail