Furthermore, because of a 1964 Act of Congress that designated bourbon "America’s Native Spirit," by law, bourbon can only be produced in the United States.
Bourbon’s history is muddled. Early settlers were certainly adept at making their own whiskeys with rye and barley to drink right off the still, both as moonshine and for "medicinal" purposes.
In Kentucky, corn was added to the mix, and somewhere down the line, barrels proved useful for both aging and easy transport to far-flung places.
Distilleries in the state were widespread by the 1800s. Buffalo Trace is the oldest continually operating distillery in America, in business for over 200 years, including during Prohibition.
Today, bourbon’s journey from grain to drink is ruled by strict regulations. It must be made from at least 51% corn, which bestows sweetness, mouth feel and a robust flavor.
Together with barley and rye or wheat, the milled grains are cooked to create a mash, which is then fermented so yeast can convert sugars to alcohol.
AJ Hochhalter, a music composer living in Kentucky and producer of "Neat: The Story of Bourbon."
It must be distilled at less than 160 proof; higher than that and you strip out the corn flavor, in which case it might as well be vodka.
Bourbon coming off the still goes into a barrel at a strictly controlled 125 proof. But it’s not just any old barrel; bourbon must be aged in brand new oak barrels that have been seasoned and charred.
Kentucky’s extreme weather is vital to bourbon’s maturation, too. Hot summers cause the wood to expand and soak in the bourbon, while cold winters force the wood to contract and expel the liquid.
This is when that patient part of the equation comes into play. The longer the aging, the more flavorful bourbon becomes, whether it’s seven years, 10 years, or longer.
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