Hop Essential Oil Research Articles

Antioxidant effectiveness between mechanisms of “Chain breaking antioxidant” and “Termination enhancing antioxidant” in a lipid model with essential oils

Lipid oxidation in foods is delayed through the use of antioxidants. The aim was to determine the oxidative stability of high oleic peanut oil and the effect of adding oregano and hop essential oils, with phenolic and no-phenolic terpenes, under 150 °C. The peanut oil was enriched with oregano and hop essential oils (0.02%). These treatments were compared with sunflower oil, high oleic peanut oil, and high oleic peanut oil with BHT (0.02%). Treatments were exposed at 150 °C for 8 h. Peroxide value (PV), conjugated dienes, and volatile oxidation compounds were measured. High oleic peanut oil was more stable than sunflower oil. Peanut oil obtained 61.9% less PV than sunflower oil. Oregano and hop essential oils protected the peanut oil; the peroxide values were 14.9 ± 0.4 and 14.6 ± 0.2 meq O2 kg−1 at 8 h, respectively. Both “Chain Breaking Antioxidant” And “Termination Enhancing Antioxidant” had similar antioxidant effects.

Variability and stability of essential oil composition in Ukrainian hop varieties

The aim of the study was to evaluate the variation in essential oil content and composition within nine distinct Ukrainian hop varieties, with a particular focus on their genetic stability and suitability for brewing applications over 11 years of their cultivation. The hydrodistillation method (Analytica-EBC 7.10) was used to evaluate hop essential oil content and gas-liquid capillary chromatography (Analytica-EBC 7.12) to discern its qualitative composition. Variability was evaluated using statistical parameters. The essential oil content across the studied varieties spanned from 0.51 to 2.58 ml/100 g of dry hop cones. The highest content was measured in the bitter-aroma variety with a special aroma – Ruslan. The predominant essential oil components, including myrcene, caryophyllene, humulene, and farnesene, collectively constituted 70.0–84.2% of the total amount. The aroma varieties displayed myrcene content typical for European varieties (with the level up to 56.2% in the Ruslan variety). Farnesene content exhibited significant variation ranging from 0.3 to 17.6% with the highest content in Saaz-type varieties (Klon 18, Zlato Polissya, and National) and the bitter type Promin variety. Humulene content ranged from 13.2 to 32.6%. Among all studied varieties, Alta displayed the least variability for all parameters evaluated (Cv = 15.2%). This study underscores the genetic basis of essential oil composition in hops, emphasizing its potential as a biochemical criterion for identifying hop breeding varieties. The study revealed, that despite annual fluctuations, the essential oil content and composition remained within passport data declared for the variety. The findings provide valuable insight into a sustainable cultivation and optimal utilization of hops in the brewing industry.

Comparative Analysis of the Essential Oil Contents of Azadrichta indica and Humulus lulpulus: Could Azadrichta indica Substitute Humulus lulpulus in Beer Brewing?

Hops (Humulus lulpulus) give beer its brewing qualities (iso-alpha acid and essential oil). Hop acid is responsible for bitterness while hop essential oil is responsible for aroma and palate fullness. The aim of the study is to investigate the potentiality of substituting hop oil with neem (Azadrichta indica) oil in beer brewing. The oils were analyzed using Fourier-Transform Infrared (FTIR) spectroscopic technique after extracting the oil by solvent extraction. Hydrocarbon and Sulphur contents were also investigated using their standard methods. FTIR results show that both oils contain similar functional groups. It was observed that some hydrocarbons (myrcene, ocimene and α and β-pinene) present in essential oil of hop were also present in neem leaf oil. Volatile sulphur compounds such as dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide present in hop oil were also found in neem oil. This study revealed that neem oil could be used as a substitute for hop oil in aroma enhancement in beer.

Effects of Dry-Hopping on Beer Chemistry and Sensory Properties-A Review.

Dry-hopping is the addition of hops to the wort on the cold side of the brewing process. Unlike standard hop additions, its main purpose is not to produce a characteristic bitterness but to extract as much of the hop essential oils as possible, which are largely lost in the standard hopping process. When dry-hopped, it is possible to obtain a beer with an aroma that is difficult to achieve when hops are used on the hot side of the brewing process. As a result, this process has become very popular in recent years, particularly in beers that belong to the 'craft beer revolution' trend. In addition, the usefulness of this process is increasing with the development of new hop varieties with unique aromas. This article presents the main components of hops, focusing on those extracted during the process. Changes in the composition of beer bittering compounds and essential oils resulting from this process are discussed. This paper presents the current state of the knowledge on the factors affecting the degree of extraction, such as hop dosage, the time, and temperature of the process. Issues such as process-related physicochemical changes, hop creep, low flavor stability, haze formation, and green flavor are also discussed.

Antioxidant-efficient indicator determinate by the relationship between β-myrcene/caryophyllene (α, β) on Hop (Humulus lupulus) essential oils under an accelerated oxidation test

The hop essential oil (Humulus lupulus) can be used as a natural additive in food to prevent lipid oxidation, replacing synthetic ones. The aim was to study the antioxidant activity of hop essential oil under accelerated oxidation conditions and determine the relationship between β-myrcene/caryophyllene (α, β) (M/Cs) as an antioxidant-efficient indicator. Sunflower oil was used as a lipid model. Five treatments were carried out (control, BHT, Chinook (CH), Cryo Citra (CYT), and Falconers Flight (F) at 0.02 %). The antioxidant efficacy was measured through free radical-scavenging activity, peroxide value, conjugated dienes, and oxidation volatile compounds. Cryo Citra essential oil showed the highest antioxidant activity, comparable with BHT, and M/Cs of 3.14 and F (0.91) and CH (0.57) showed good performance in the accelerated oxidation test while Chinook showed the best free radical-scavenging activity. The M/Cs relationship can be used as an antioxidant-efficient indicator with values biggest than 0.90.

Effect of treatment of Fusarium head blight infected barley grains with hop essential oil nanoemulsion on the quality and safety of malted barley.

Fusarium mycotoxin contamination of malting barley has been a persistent food safety issue for malting companies. In this study, the effect of hop essential oil (HEO) nanoemulsion on fungal biomass and mycotoxin production during the malting process was evaluated. Furthermore, the localization of fungal hyphae on the surface and inside the tissue of barley and malts was observed. The application of HEO nanoemulsion reduced fungal biomass and deoxynivalenol (DON) contents at each stage of the malting process as compared to control. During malting process, the fungal hyphae on kernel surfaces was reduced appreciably after steeping. However, the increment of hyphae was observed between the husk and testa layer of barley after germination than raw barley grains. In addition to its antifungal activity, the antioxidant activity of HEO in the treated malts suppressed the formation of aldehydes. This study lays the foundation for the utilization of HEO in the malting industry.

How maturation time affects the chemical and sensory profile of pale lager beer

The maturation of beer is an important production step with an impact on its quality. Changes in the chemical and sensory profile between 2 and 6 weeks of cold maturation were evaluated in pilot brews (200 l) of a pale lager of 11% and 15% original gravity. In addition to the basic analytical parameters and shelf life, volatiles, hop essential oils, fatty acids, amino acids and stale flavour aldehydes were monitored. The sensory quality of the beers was evaluated using descriptive method. The dynamics of changes in the monitored groups of analytes during maturation of the tested variants was different, but without substantial influence on the overall impression and shelf life of the beer. Under the experimental conditions, it was possible to reduce the maturation time of a common Czech-style lager to 2 weeks of cold lagering. The gradual slight improvement in the overall impression of beers brewed at original gravity indicates the need for a long maturation period to fine-tune the sensory profile of premium lagers. A short maturation period of 2 weeks appears to be beneficial for beers brewed using a high gravity brewing protocol. The findings obtained can be a useful guide for optimising the maturation of Czech-style lager in practice, although the dynamics of changes in the monitored substances and their influence on the sensory characteristics of the beer may be to some degree different when scaled up to operational practice.

Effect of Extraction Time on the Yield, Chemical Composition, and Antibacterial Activity of Hop Essential Oil Against Lactic Acid Bacteria (Lactobacillus brevis and Lactobacillus casei) Beer Spoilage.

Hop essential oil (EO) generates interest for its antioxidant and antimicrobial properties, in addition to the volatile compounds that are responsible for the hop aroma in beer. Thus, the objective of this study was to evaluate the chemical composition, EO yield, and antibacterial activity of hop essential oil from hops of the Chinook variety against lactic acid bacteria (Lactobacillus brevis and Lactobacillus casei) at different times of extraction. EO extraction was performed by hydrodistillation at different times. By analyzing the chemical composition by gas chromatography and mass spectrometry, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. The major compounds of hop EO were α-humulene, β-myrcene, and β-caryophyllene, and the extraction yields were 0.67, 0.78, and 0.85% mass of EO per mass of hops pelletized hops (m/m), for extractions of 90, 180, and 300min, respectively. The EO obtained in 90min was efficient against L. casei at 2.5mg/mL (MIC) and 5.0mg/mL (MBC), and the 300min one against L. brevis at 2.5mg/mL (MIC) and 25mg/mL (MBC). The antibacterial activity was affected by the chemical makeup of the oil, revealing that the hop EO extracted in 300min was the most efficient among the other extraction times.

The Fungicidal Effect of Essential Oils of Fennel and Hops against Fusarium Disease of Pea

Modern integrated farming systems encourage the search for alternative (non-chemical), highly effective methods of plant protection. In this study, the fungistatic effect of fennel essential oil (FEO) and hop essential oil (HEO) on fungal growth and their ability to treat Fusarium wilt was investigated. The study was conducted in vitro and in pot experiments. The severity of infection was assessed by disease index (DI), presence of Fusarium culmorum gDNA (qPCR) and anatomical analyses of infected plant tissue using an optical (OM) and scanning electron microscope (SEM). Laboratory analyses showed that FEO inhibits mycelial growth of Fusarium fungi (F. avenaceum, F. culmorum, F. equiseti, F. oxysporum, F. poae, F. solani, F. sporotrichioides, F. tricinctum), Botrytis cinerea and Cylindrocarpon destructans more effectively than HEO. FEO at a concentration of 2000 ppm completely inhibited the growth of F. culmorum, F. poae and B. cinerea. Both essential oils reduced the severity of Fusarium wilt caused by F. culmorum in pea plants (DI, OM, SEM). The qPCR shows that both essential oils are also able to reduce the synthesis of trichothecenes in the tissues of infected pea plants. The results of the study suggest that FEO and HEO represent a broad spectrum bio-fungicidal agent that can be applied directly to plants at a concentration of 500 ppm, greatly reducing the level of infection.

Extraction of hops pelletized (Humulus lupulus) with subcritical CO2 and hydrodistillation: Chemical composition identification, kinetic model, and evaluation of antioxidant and antimicrobial activity

Hop essential oil and hop extract using carbon dioxide (CO2) are products with high added value because they have bioactive and sensory properties. In this context, the objective of this study was to obtain and characterize essential oil and extracts from pelleted hops of El Dorado, Polaris, Hallertau Blanc and Callista varieties using hydrodistillation and subcritical CO2 extraction methods. Extraction yield ranged from 0.38 % to 1.97 % (m/m) for essential oils and from 8.76 % to 15.35 % (m/m) for extracts using subcritical CO2. The chemical compositions of the essential oils were mainly monoterpene (18.14 % to 29.91 %) and sesquiterpene (46.01 % to 59.03 %) hydrocarbons and for the extracts were sesquiterpene hydrocarbons (33.05 % to 71.90 %) and oxygenated sesquiterpenes (14.80 % to 34.89 %). The extracts showed better antioxidant activity than essential oils due to the presence of phenolic compounds and flavonoids. Hop extracts showed some antimicrobial activity, but essential oils did not demonstrate antimicrobial potential. Hop extracts obtained with subCO2 have the potential to be used in the brewing industry as a flavoring and as natural antioxidants.

Encapsulation of hop (Humulus lupulus L.) essential oil for controlled release in the non-alcoholic beverage application

In order to increase the stability of hop ( Humulus lupulus L.) essential oil (HEO) and diversify its application into hot beverages, CAPSUL®, modified food starch, was used as the wall material to encapsulate HEO at the mass ratio of 2:1 through spray drying under 180 °C. The resultant microcapsules were applied to the non-alcoholic hop tea for the first time and their release kinetics in this matrix were analyzed by gas chromatography-mass spectrometry (GC-MS). Results showed that the reconstituted HEO emulsion possessed fine droplet size (3.295 μm) and high zeta potential (−22.50 mV). The resultant HEO microcapsules exhibited low moisture content (1.249%), suitable bulk density (0.2934 g/mL), good swelling capacity (2.235 g/g dry solids), low color difference (6.310), desirable morphological characteristics, high encapsulation efficiency (92.02–95.45%) and high flavor retention (57.13–71.15%). Each target aroma compound had its specific release behavior and mechanism from HEO microcapsules, among which β -myrcene and methyl octanoate showed the highest and lowest cumulative release respectively. This might be associated with their different volatilities, polarities, function groups and molecular sizes, or their varying hydrogen-bond formation capability at the entrance of starch helix. Most importantly, HEO microcapsules showed significant aroma increasing and stabilizing effects on the hop tea product during storage. These ideal characteristics of HEO microcapsules demonstrated the great potential of diverse essential oil microcapsules as the promising flavoring agent in a variety of hot beverage matrices. • Overall desirable physicochemical properties were observed in HEO microcapsules. • HEO microcapsule showed satisfactory encapsulation efficiency and flavor retention. • Each target aroma compound had a specific release mechanism during 40 °C of storage. • HEO microcapsule was an effective flavoring agent in the hot beverage matrix.

Hydrolats from Humulus lupulus and Their Potential Activity as an Organic Control for Varroa destructor

Varroa destructor is a parasitic mite, which is considered a severe pest for honey bees causing serious losses to beekeeping. Residual hydrolats from steam extraction of hop essential oils, generally considered as a waste product, were tested for their potential use as acaricides on V. destructor. Four hop varieties, namely Cascade, Spalt, Victoria, and Mapuche, showed an interesting performance as feasible products to be used in the beekeeping industry. Some volatile oxidized terpenoids were found in the hydrolats, mainly β-caryophyllene oxide, β-linalool, and isogeraniol. These compounds, together with the presence of polyphenols, flavonoids, and saponins, were probably responsible for the promissory LC50 values obtained for mites after hydrolat exposition. Victoria hydrolat was the most toxic for mites (LC50: 16.1 µL/mL), followed by Mapuche (LC50 value equal to 30.1 µL/mL), Spalt (LC50 value equal to 114.3 µL/mL), and finally Cascade (LC50: 117.9 µL/mL). Likewise, Spalt had the highest larval survival, followed by Victoria and Mapuche. Cascade was the variety with the highest larval mortality. In addition, none of the extracts showed mortality higher than 20% in adult bees. The Victoria hydrolat presented the best results, which makes it a good compound with the prospect of an acaricide treatment against V. destructor.

Changes in Hop (Humulus lupulus L.) Oil Content and Composition during Long-Term Storage under Different Conditions.

Hop essential oil, in addition to alpha-acids, is one of the most valuable parameters for brewers, since it is responsible for beer aroma. The hop oil content and hop oil chemical composition deliver various aromas to beer. During storage, the hop chemical composition undergoes many physical and chemical changes that impact its quality. The main purpose of our study was to evaluate the changes occurring in hop oil content and its chemical composition during two years of storage under four different conditions (anaerobic, aerobic, cold room (4 °C), and room temperature) in the form of cones and pellets, supplied by local suppliers in Slovenia. Hop oil content and composition were determined by steam distillation and GC-FID. The greatest decrease in hop essential oil content occurred when the hops were stored under aerobic conditions and at room temperature. Monitoring of eight hop oil compounds under various conditions revealed different behaviors of the changes. The best storage conditions were anaerobic at low temperatures. Oxygen resistance was lower for pellets than for hop cones, whereas high temperature was more devastating for hop cones. In addition to the storage conditions, the hop variety and form were important factors regulating the extent of changes in hop oil content and chemical composition.

Antifungal activity, mycotoxin inhibitory efficacy, and mode of action of hop essential oil nanoemulsion against Fusarium graminearum

This work aims to investigate antifungal, mycotoxin inhibitory efficacy of the hop essential oil (HEO) nanoemulsion and their mode of action (MOA) against Fusarium graminearum isolate, a fungal pathogen causing Fusarium Head Blight (FHB) in cereal crops. The HEO, primarily consisting of terpenes and terpenoids, was encapsulated in nanoemulsion droplets. Physically stable HEO-in-water nanoemulsion was fabricated using 0.5 wt% of tween 80 and 5 wt% oil phase comprising 30 % of Ostwald ripening inhibitor and 70 % of HEO. In terms of antifungal effect, HEO nanoemulsion could not only effectively inhibit mycelial growth and spore germination of F. graminearum isolates, but also remarkably suppress the production of deoxynivalenol (DON) and its derivatives in rice culture by applying 750 μg of HEO/g rice. Our studies on the MOA showed that HEO nanoemulsion could alter the contents of total lipid and chitin in outer cell membrane as well as damaging cytoplasmic membrane.

Study on the Composition of Hop Terpenes and Terpenoids by Steam Distillation and Effects on Beer Flavor by an Ale Yeast

Model systems of adding three distillates (hop oil, water-soluble aqueous, and residual aqueous) in model wort (buffer) and wort were used to produce model beers and special beers, respectively (with an ale yeast and fermentation at 18 °C). The attributes of hoppy flavor and organoleptic quality were comprised of sustained, surged, generated, or diminished oxygenated compounds and hydrocarbons by yeast biosynthesis in hop essential oil and non-volatile precursors. The matrix of content and instrumental composition of oxygenated terpenoids and hydrocarbons (terpenes and sesquiterpenes) and sensorial profile of model systems was directionally correlated to the matrix and sensory of the early hopped, late hopped, and dry hopped beers. The occurrence of hop aroma profile of the residual aqueous is reminiscent to traditional early kettle hopped beer. The water-soluble volatile components added beer were remarkably close to the distinctive odor profile of late hopped beer. However, dry hopped beer was seemingly a coupling of the hop oil and the water soluble aqueous added beers, but its perception was closer to the latter. The mechanism of the growth of nerol, citronellol, and methyl geranate via a reversed biosynthesis of free linalool by ale yeast and fermentation at 18 °C is contrary to a pathway via geraniol from the hop oil or the water-soluble aqueous. Free linalool was sustained after yeast hydrolysis of linalyl glycoside and related to metabolites in the residual aqueous due to sluggish yeast activity in the model wort (buffer) but not in the wort.

Hemp (Cannabis sativa L., Kompolti cv.) and Hop (Humulus lupulus L., Chinook cv.) Essential Oil and Hydrolate: HS-GC-MS Chemical Investigation and Apoptotic Activity Evaluation.

In this study, essential oils (EOs) and hydrolates (Hys) from Italian hemp (Cannabis sativa L. Kompolti cv.) and hop (Humulus Lupulus L., Chinook cv.) supply chains were chemically characterized and tested to investigate their apoptotic potential for the first time. Headspace–Gas Chromatography–Mass Spectrometry (HS-GC-MS) techniques were performed to describe their volatile chemical profile, highlighting a composition rich in terpene derivatives such as monoterpenes and sesquiterpenes among which β-myrcene, limonene, β-caryophyllene and α-humulene were the main constituents of EOs; in contrast, linalool, cis-p-menth-2,8-dien-1-ol, terpinen-4-ol, α-terpineol, caryophyllene oxide, and τ-cadinol were found in the Hys. The cytotoxicity activity on human leukemia cells (HL60), human neuroblastoma cells (SH-SY5Y), human metastatic adenocarcinoma breast cells (MCF7), human adenocarcinoma breast cells (MDA), and normal breast epithelial cell (MCF10A) for the EOs and Hys was studied by MTT assay and cytofluorimetric analysis and scanning and transmission electron microscopy were performed to define ultrastructural changes and the mechanism of cells death for HL 60 cells. An induction of the apoptotic mechanism was evidenced for hemp and hop EOs after treatment with the corresponding EC50 dose. In addition, TEM and SEM investigations revealed typical characteristics induced by the apoptotic pathway. Therefore, thanks to the integration of the applied methodologies with the used techniques, this work provides an overview on the metabolomic profile and the apoptotic potential of hemp and hop EOs and, for the first time, also of Hys. The findings of this preliminary study confirm that the EOs and Hys from Cannabis and Humulus species are sources of bioactive molecules with multiple biological effects yet to be explored.

Hops components and oral health

• Hop may have positive effect on oral health, considering its role in systemic health. • Antimicrobial and antioxidant activities of hops may be beneficial to oral health. • Hops have potential against oral diseases such as dental caries and periodontitis. • Xanthohumol has potential against oral pathogens; Streptococcus and Porphyromonas . Hops ( Humulus lupulus L.), a major constituent of beer, is composed of resins, polyphenols, hop essential oils, various proteins, cellulose, and water. Hops and hop components are well-known for their antimicrobial effects on bacterial growth. Hop components contribute to human health, and numerous studies have shown hops as potent antimicrobial, anti-inflammatory, and anticancer agents. Most health benefits are derived from three main hop components: polyphenols, bitter acids, and essential oil. The effect of hop components on oral health cannot be ignored, considering their role in systemic health. Hop components may have potential uses in treating oral diseases, such as dental caries, periodontal diseases, oral lichen planus, oral candidiasis, and others. However, few studies have focused on the effects of hops on oral health. This review discusses the beneficial effects of hop components on systemic health and potential applications in oral diseases.

Hop (Humulus lupulus L.) Essential Oils and Xanthohumol Derived from Extraction Process Using Solvents of Different Polarity

This study evaluates the content of essential oils (EOs) and prenylated flavonoid Xanthohumol (XN) in extracts of Slovenian hops, cultivar Aurora, obtained by using fluids of different polarity. It is a continuation of our previous work, investigating the extraction of bitter acids from hops. Extraction was conducted semi-continuously, using sub- and supercritical fluids of different polarity, i.e., carbon dioxide (CO2) and propane as non-polar and dimethyl ether (DME) as the polar solvent. The experiments explored a temperature range between 20 °C and 80 °C and pressures ranging from 50 bar to 150 bar. The content of XN in extracts was analysed using high-performance liquid chromatography and experiments demonstrated the largest concentration of XN was obtained using DME. In order to analyse the EO components in extracts, connected with a distinct odour, the steam distillation of extracts was performed and GC analysis was employed. Hop oil derived from CO2 extracts at specific conditions, had the highest relative concentration of linalool, β-caryophyllene and α-humulene, and oil derived from propane extracts had the highest content of all other five selected components (myrcene, geraniol, farnesene, α-selinene and δ-cadinene). The relative content of the investigated EO components in DME extracts was similar to that in propane extracts.

On the synergy/antagonism of selected terpenes in the effect on lipid membranes studied in model systems

In this work the influence of the mixtures of four terpenes on the lipid monolayers and bilayers imitating bacteria membrane was analyzed. The aim of these investigations was to verify possible synergistic/antagonistic effects occurring between terpenes and affecting their influence on membranes. The studies were performed for major and minor components of the hop essential oil, namely: β-myrcene, α-humulene, E-β-Farnesene and limonene. The experiments on monolayers were based on the studies on penetration of terpenes and their mixtures into model systems, on the surface pressure-area measurements, and Brewster angle microscopy studies, while for bilayers they involved the hydrodynamic diameter, zeta potential and steady-state fluorescence anisotropy measurements of liposomes. Based on the collected results it was concluded that the synergy occurring between selected terpenes increases the effect of their mixtures on monolayers and bilayers as compared to particular components. Among the studied mixed terpene systems the equimolar myrcene/humulene/farnesene/limonene system was found to penetrate the most strongly into the monolayer and change its morphology as well as to make the bilayer more fluid. Additionally, from the comparison of these results with those published for the hop oil it was summarized that neither the studied mixtures nor the individual studied terpenes change the properties of the model membranes as effectively as the total extract. Thus, the action of the hop oil on membrane is not determined by its major components but it is rather the result of the interactions and synergy between major and minor components.

Evaluation and Optimization of APGC Parameters for the Analysis of Selected Hop Essential Oil Volatiles.

Hop essential oil is a mixture of several hundred volatile metabolites that quantitatively and qualitatively distinguish hop varieties. Given the commercial relevance of hops in the brewing industry and the complexity of hop oil, analytical tools enabling a comprehensive characterization of oil constituents are required. At this, atmospheric pressure chemical ionization interfaced to gas chromatography and high-resolution mass spectrometry (APGC–MS) is a promising option that combines soft ionization, high sensitivity, and high resolution. While high sensitivity is required to detect minor or trace-level volatile metabolites, soft ionization and high resolution enable the reliable identification of unknowns based on exact masses of the molecular ion or the protonated molecule. Twenty-two volatile metabolites typically found in hop oil were studied in respect to their APGC ionization behavior. For 15 compounds, APGC–MS did not yield high molecular ion or protonated molecule intensities and considerable in-source fragmentation was observed. APGC–MS parameter optimization (cone gas flow and cone voltage) was able to yield the maximum absolute intensity for the base peak. However, in-source fragmentation could not be prevented, leading to spectra with either the protonated molecule or a characteristic fragment ion as the base peak. APGC–MS operated under optimized parameters was applied to a hop essential oil sample to verify the effect of optimization. By estimating the limit of quantification for the 22 compounds, it is concluded that APGC–MS is well suited to analyze major, minor, and trace-level volatiles from hops.