Lupulin glands from 139 plants (39 cultivars/advanced selections) were analysed by Raman and ¹H NMR spectroscopy, and head-space solid-phase microextraction (HS-SPME) GC-FID. The digital X,Y-data were subjected to principal component analysis (PCA) and the results compared with conventional analyses of extracts of whole hops from the same plants. Quantitative ¹H NMR analyses were also done for the bitter acids.

Raman spectroscopy rapidly identified hops cultivars with high xanthohumol concentrations and high a:ß bitter acid ratios. ¹H NMR spectroscopy was slower, requiring a solvent extraction, but distinguished cultivars by cohumulone content as well as a:ß acid ratios. HS-SPME-GC rapidly distinguished aroma hops with high myrcene and farnesene contents, and pinpointed a novel selection with unusual sesquiterpenes. The quantitative NMR analyses showed correlations between bitter acid concentrations related to biosynthetic pathways.