American Imperial Stouts are barrel aged, mostly in bourbon and whiskey barrels, while some are infused with coffee or chocolate. The Alcohol content ranges vary, but tend to be quite high,usually over 9%. The beer style is full-bodied with rich roasted flavors far surpassing normal stouts. It has a strong flavor, takes longer to spoil than other beers, increased in alcohol content with age, was significantly cheaper than other beers, and was not easily affected by heat. Most of beers tend to have cleaner alcohol flavors, higher hop levels, and more residual sweetness.