Characterisation of Swiss wild hops (Humulus lupulus): agronomic, genetic, phytochemical and aromatic diversity compared with commercial varieties

Abstract

Why was the work done: Wild hop populations represent an underexplored resource for the development of new hop varieties with distinctive flavour profiles and improved agronomic performance. This study evaluated the potential of Swiss wild hops as both breeding material and as candidates for use in brewing. How was the work done: Wild hop accessions (62) from diverse biogeographical regions of Switzerland were characterised and compared with 14 commercial hop cultivars. Genetic diversity, agronomic performance, and chemical composition, including essential oils and bittering compounds, were analysed. What are the main findings: Swiss wild hops exhibited high genetic diversity and were differentiated from commercial cultivars. On average, wild accessions showed higher yields than commercial varieties. Although essential oil content was generally lower in wild hops, some selected accessions displayed promising aromatic profiles, with several genotypes surpassing commercial cultivars in specific compounds. However, commercial cultivars typically contained higher levels of bittering compounds, but several wild genotypes achieved a comparable concentration. Why is the work important: These findings highlight the potential of Swiss wild hops as a resource for breeding and for diversifying the raw materials used in brewing. The identified variability in agronomic and chemical traits supports the development of more sustainable hop varieties with novel flavour characteristics, contributing to innovation in the brewing industry.