100 Years of Hop Chemistry and Its Relevance to Brewing

Chemical research has shown that the α-acids are the main quality factors of hops and that the bitter taste of hopped beer derives from the iso-α-acids. This has provided the basis for improvements in hop breeding, conditioning, extraction, use, analysis etc. Structural chemical development of hop constituents was completed about ten years ago. At the present moment the accent of chemical research is on analytical aspects, mainly using High Performance Liquid Chromatography. From the standpoint of the brewery the situation of chemical research is not completely satisfactory, since a clear understanding of the more subtle chemical quality factors of hops and their impact on beer quality is still lacking. Hops are much more important for beer than is generally estimated, even in brewery circles.