Varietal characterization of hop (Humulus lupulus L.) by GC–MS analysis of hop cone extracts

Abstract

An approach is described for use in the varietal characterization of hop (Humulus lupulus L.) varieties. The study focuses on commercial hop varieties and was timed to coincide with the 2008 commercial hop harvest in Tasmania, Australia. Analysis of hop extracts was performed using GC-MS. A 60 m capillary column was employed to increase efficiency to permit the use of a quadrupole mass spectrometer in place of a time of flight mass spectrometer that is more commonly used for this type of analysis. A set of characterization functions were derived from discriminant analysis which were highly suitable for varietal characterization of the eight commercial varieties included in the study, namely Willamette, Victoria, Pride of Ringwood, Cascade, Southern Hallertau, Millennium, Southern Saaz, and Super Pride.

Characterisation of four popular Polish hop cultivars

“…The highest value was obtained from the cones of Marynka (2.22% v/w), while the lowest in Lubelski (0.86%). This result is in agreement with the classification proposed above (De Cooman et al ., ; Shellie et al ., ) where the EO yield is generally lower in aroma than in bitter cultivars. The variability in the chemical composition of the four EOs regarded the relative percentages of both the main constituents and their chemical classes.…”

“…Since it was established that the chemical composition of EOs and the amounts of bitter alpha/beta acids depend only from the hop cultivar (Likens & Nickerson, 1967), the investigations and identification of the leading compounds with positive and negative influence on the aroma grade based on gas chromatography/mass spectrometry (GC/MS) and the alpha acid concentrations are used for the elucidation and classification of classical and new hop cultivars (Kralj et al, 1991). For the needs of the brewing industry, hop cultivars are classified into three main groups: aroma, bitter (dual purpose) and high alpha (De Cooman et al, 1998;Shellie et al, 2009). The aroma cultivars are divided into two subgroups: fine-aroma and aroma.…”

Chemometric Profile of Root Extracts of Rhodiola imbricata Edgew. with Hyphenated Gas Chromatography Mass Spectrometric Technique

“…Profiling of metabolites in plant extracts permits the complete phenotyping of genetically or environmentally adapted plant systems and such investigations draw on simple extraction procedures that have been shown to be very robust and have permitted broad range of high-throughput applications in plant metabolomics. [25]–[27].…”

Determination of the botanical origin of hops (Humulus lupulusL.) using different analytical techniques in combination with statistical methods

“…Hop essential oils can be used to identify hop varieties based on identification with gas chromatography (GC), using standard steam distillation for isolation of oils. Much research work has been conducted to identify hop varieties . With GC using capillary columns, around 400 components of hop essential oils have been found and around half of them have also been identified .…”