Trans-humulinones – Synthesis, Structural Characterization and Comparison to Cis-humulinones

Thursday, August 14, 2025

11:10am - 11:35am PDT

Location: Springs Ballroom F

Presenting Author(s)

HJ

Hershel Jude, PhD

Lead Scientist II - Hops
Kalsec Inc
Kalamazoo, MI, USA

Co-Author(s)

DK

Daniel C. King (he/him/his)

R&D Brewer
Kalsec Inc
Kalamazoo, MI, USA
MJ

Matt Jones

Director of Hops Innovation
Kalsec Inc
Kalamazoo, Michigan, United States
JS

John Scholten

Scientist I - Hops
Kalsec Inc
Kalamazoo, Michigan, United States

Abstract: cis-Humulinones, formed by the oxidation of hop alpha acids (Humulones), are an important source of bitterness in dry hopped beers. This presentation will provide an overview of cis- and trans-n-Humulinone synthesis and structural characterization. Unlike isohumulone, which is found as a nearly racemic mixture in beer, cis-Humulinones are the major enantiomer produced when humulones are oxidized to humulinones. cis-Humulinones are isomerized to trans-humulinones under alkaline conditions in a 10:1 trans- to cis-Humulinone ratio. The structure has been confirmed using NMR Spectroscopy, Mass spectrometry, and X-ray Crystallography. The light stability, oxidative stability, and organoleptic profile of Humulinones and beers brewed with cis- and trans-Humulinones will be described.