Vertical beer tastings offer a sensory experience that uncovers the changes beer undergoes with age. These beers are the same base beer recipe (in this case, Tractor’s Russian Imperial Stout aka Luna de los Muertos) but showcase yearly changes of ingredients, storage, and brewing methods. Basically, as beer ages, bitterness and alcohol perception fades whilst sweetness increases. The 2015 is the most mellow and easy drinking of the later mentioned flavors (ABV 8.2, IBU 80, og 1.077- fg 1.022).The 2016 has more alcohol warmth, higher bitterness and has pronounced barrel character (ABV 8.2, IBU 80, og 1.077 fg 1.022). 2017 is hot off the presses and in you face Russian Imperial Stout with strong wood, chocolate and alcohol (ABV 11, IBU 80, og 1.105 fg 1.032).