THE AROMA OF HOPS I. ORIGIN AND IDENTIFICATION OF HOP AROMA SUBSTANCES

Abstract

Gas chromatography of the head space was used to follow the evolution of hop aroma under different conditions of storage. Aroma from fresh hops contains mainly myrcene, which disappears as the hops get older. Meanwhile new, more volatile substances are formed, especially by degradation of the well‐known α‐ and β‐acids; when hops are kept in closed storage the aroma therefore soon takes a composite character. When the formed volatiles are allowed to escape, the aroma of hops becomes poorer with age, to disappear almost completely in the end. Twenty‐five compounds have been identified in the more volatile fraction of hop extracts. 1968 The Institute of Brewing & Distilling