Whirlpool Hop Additions and Added Bitterness

 There is no doubt that the explosion in popularity of IPA has changed the landscape for craft beer producers and consumers, as well as homebrewers.  Between the evolution of the style to fit the wants of the drinking public, the many stylistic offshoots of IPA that have become commonly available, and the increasing quality of flavor and aromatics that many brewers seem to be achieving, it is no wonder that exploration of ingredients and techniques for brewing IPA is at an all-time high.
 Many of the best IPAs are made with generous additions of hops both late in the boil and post-boil, or in the whirlpool.  There is even a technique that has spawned off of this thinking called hop bursting, where massive additions of flavor and aroma hops are used to obtain bitterness, in addition to huge amounts of hop character in both flavor and aromatics.
 Mitch Steele, formerly of Stone Brewing Company, has been one of the foremost experts on this technique, and has discussed it in numerous forums, including his book, IPA: Brewing Techniques, Recipes and the Evolution of India Pale Ale, presentations at the National Homebrewers Conference and in an article in the November/December 2013 edition of Zymurgy magazine.  In that article, in reference to whirlpool hop additions, Steele stated, “Many brewers neglect to consider the bitterness obtained from this addition, but it can be substantial, depending on the volume of hops added.”
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