The American whiskey boom of recent years has prompted a good deal of experimentation. Lincoln Henderson, who spent 40 years as Brown-Forman’s master distiller, placed himself at the forefront of this movement with the 2011 introduction of his Angel’s Envy label, whose inaugural release was a bourbon finished in port barrels. With Angel’s Envy Rye, Henderson has again ventured into new territory. Distilled from 95 percent rye grain, the whiskey ages for at least six years in new, charred American oak barrels b…