It was the Irish and Scottish distillers who brought the wonderful libation to America. Often, American whisky possesses a rustic quality, a sort of tangy top note too. This is down to the widespread use of virgin oak for the majority of their whiskeys. Tennessee whiskey differs only slightly from bourbon. It is a sour mash whiskey that is filtered through sugar maple charcoal prior to aging. This technique is known as the Lincoln County Process. There are only two brands that produce Tennessee whiskey: George Dickel and, of course, Jack Daniel's.