Exploring the multisensory perception of terpene alcohol and sesquiterpene rich hop extracts in lager style beer.

Understanding the contribution of hop essential oil to the multisensory profile of beer is known to be challenging because of its chemical and sensory complexity. Limited research has been conducted investigating hop-derived volatiles' role in the modulation of taste and mouthfeel sensations. Supercritical CO₂ can be used to extract specific fractions from hop oil, thereby enabling the localisation of compounds responsible for different sensory impressions. Terpene alcohol and sesquiterpene fractions were extracted from a Magnum hop oil and further fractionated into seven sub-fractions and individual compounds. All extracts were evaluated in lager (4.5% v/v) by a trained panel (n = 10) using a newly developed attribute lexicon and following a sensory descriptive analysis approach. The sensory data was analysed using ANOVA, followed by Tukey's test (HSD) and correlated with chemical profile data obtained by gas chromatography-mass spectrometry (GC-MS) by Principal Component Analysis. The study revealed evidence for hop extracts to impart multisensory characteristics to beer due to sensory interactions within and across modalities. The monoterpene alcohols-rich fractions and particularly geraniol, added fruity- and floral aromas and flavours, modified the sweetness and induced a smooth bitterness in the beer matrix. Flavouring the beer with sesquiterpene fractions resulted in a harsh bitterness sensation. Contrary to previous findings, the humulene epoxides fraction appeared to have limited effects on lingering bitterness and astringency, illustrating the need for temporal sensory assessments in future studies. This research shows that splitting hop oil into fractions and sub-fractions provides a source of natural, sustainable flavouring preparations with distinct sensory characteristics.