Peter Fowler, 58, who has been brewing since 1975 and runs Pitstop Brewery created the eight per cent beer The Hop, rated for its bitterness at 323 International Bittering Units - setting the new world record for the Bitterest beer. The previous Guinness world record for the Bitterest beer was about 200, for an American beer Devil Dance Triple IPA. Two independent laboratories in Sunderland and Kalamazoo, Michigan, have confirmed The Hop is more bitter than any other beer on sale that has been tested. To claim the world record, Mr. Fowler used powerful hop varieties of Simcoe, Centennial and Chinnok, and added hop extract Isolone to preserve the extreme bitterness. American laboratory Kalsec Inc rated its bitterness at 323 International Bittering Units (IBUs); the highest previously recorded is around 200, for an American beer Devil Dance Triple IPA.