Formulated by German surgeon Johann Gottlieb Benjamin Siegert, who served under Marshall von Blücher at the battle of Waterloo, angostura bitters are the most widely known bitters today. Dr. Siegert created the bitter elixir (based on angostura bark, gentian root, rum and other ingredients) as a tonic to stimulate the troops' lagging appetites and improve their health. Although bitters are still taken as a digestif, angostura bitters are often used today as a flavoring in foods and drinks and are essential in many cocktails such as the manhattan and old fashioned. At 90 proof, angostura bitters are the most potent among this genre.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.