The history of Bourbon, that quintessential American whiskey, is a matter of some debate. In simple terms, we know settlers from the east brought well-known distilling practices to the western frontier of America in the mid-late 1700’s. The region, soon to become Kentucky, was suitable for whiskey production by virtue of its tracts of available farmland (for growing corn), reserves of limestone filtered water, and abundant oak trees. By the 1840’s Bourbon was the name given to almost all corn-based whiskey distilled west of the Alleghenies. This moniker distinguished it from the rye-based whiskey found in the east.
Although the name Bourbon was commonly used, it was not until May 4, 1964 that Congress granted Bourbon official recognition as a ?distinctive product of the United States? and enacted laws regarding production and quality standards. The regulations state that ?Bourbon? be produced from a fermented mash made with a minimum 51% corn. The original flavor and color of the spirit cannot be altered or filtered in any way before bottling. This differs from other whiskies that are filtered through charcoal to mellow or smooth out the taste). A key point of the federal regulations requires Bourbon be stored and aged in new, charred white oak barrels for a minimum of two years. The distinctive flavors, aroma and character of Bourbon are a direct result of aging in these barrels.
Oak is utilized because of its distinct chemical and physical properties. It is a strong wood, and stands up to the heat, bending and shaping of the barrel construction process. Also, oak contains no resins that might add strong or unpleasant flavors to the spirit, and thus is considered a ?pure? wood. Perhaps most importantly, the heat used in the barrel making process chemically transforms the wood and allows it to impart flavors and color to the stored spirit.
Barrels used in producing ?Straight Bourbon Whiskey? are used only once. After construction, the white oak barrels are subjected to two heat treatments. In the first treatment, called ?toasting?, new barrels are held over a low fire for approximately 12 minutes. Toasting gives the barrel its distinctive red/brown color and also caramelizes natural sugars in the wood.
The second heat or seasoning treatment subjects the interior of the barrel to intense flame for a brief time (1 minute or so).
This process leaves a layer of black char (carbon) on the inside of the barrel. There are various degrees of charring, rated one to four. The amount of charring affects the types of flavors and aromas the barrel will impart to the stored whiskey as it ages. Most Bourbon is aged in barrels charred to level three or four.
A charred barrel has dramatic influence on the maturing whiskey. The black surface char or carbon removes sulphur compounds from the aging spirit. The charring process also continues the caramelizing of natural wood sugars, which are absorbed by the whiskey.
As Bourbon ages it ?breathes? in the barrel. This means the spirit expands into the wood in warm temperatures and contracts out of it in cooler temperatures.Color and flavor are transferred to the whiskey (new whiskey is colorless before barrel aging) while it is in the wood, making the warm summer months critical in the aging process. This ?breathing? continues until the whiskey is removed from the barrel and bottled. For Bourbon, more time in the barrel results in more flavor.
During the aging process, a small amount of whiskey is lost to evaporation and leakage. Distillers refer to this loss as the ?angels’ share?. The angels must be very happy.
No comments:
Post a Comment