Extraction of volatile organic compounds from leaves of Ambrosia artemisiifolia L. and Artemisia annua L. by headspace-solid phase micro extraction and simultaneous distillation extraction and analysis by gas chromatography/mass spectrometry

This study was designed to analyze the volatile organic compounds in the leaves of Ambrosia artemisiifolia L. and Artemisia annua L. from Korea. For extraction of volatile compounds, headspace-solid phase micro extraction (HS-SPME) and simultaneous distillation extraction (SDE) were applied and analyzed by gas chromatography/mass spectrometry (GC/MS). From the results, SDE extraction was found to give the highest concentration of volatile compounds with an average concentration of 1,237.79 mg/kg for A. annua L. leaves compared to 1,122.73 mg/kg by HS-SPME technique. A total of 116 volatile organic compounds were identified, including 76 similar volatile organic compounds detected by both the methods of extraction in leaves of subject species at varying concentrations. Among these 33 volatile organic compounds were reported for the first time from the subject plant species. Thus the present research findings extend the characterization of volatile organic compounds from leaves of A. annua L. and A. artemisiifolia L. species and reported some distinguishing compounds which may be used for their discrimination.     

Optimization of equilibrium headspace analysis of volatile flavor compounds of malaysian soursop (Annona muricata): Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS)

Headspace solid-phase microextraction (HS-SPME) coupled to comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS) was applied for equilibrium headspace analysis of Malaysian soursop (Annona muricata) volatile flavor compounds. A two-level fractional factorial design (2^5-1) was used to determine the effect of SPME variables, namely, SPME fibers, adsorption temperature, extraction time, amount of salt, sample amount and sample concentration on the extraction efficiency of volatile flavor compounds. A total of 37 volatile compounds were identified, comprising 21 esters, 6 alcohols, 3 terpenes, 2 acids, 2 ketones, 2 aldehydes and an aromatic with different hydrophobicities (log P) ranging between −0.14 and 4.83. Extraction using 10 g of diluted (5% w/w) blended soursop pulp with CAR/PDMS fiber at 25 °C for 30 min and 30% (w/w) of NaCl under stirring mode resulted in the highest extraction efficiency of volatile flavor compounds. The principal component analysis score discriminated the influence of SPME variables on the equilibrium headspace concentration of target volatile compounds.     

Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder

Delipidation was studied as a way to dearomatise a non-conventional protein powder obtained from Eisenia foetida earthworms. In the first step, we studied the impact of several factors such as solvent type, extraction method and particle size on the yield of extracted lipids. Lipid extraction from samples was considerably improved using an ultrasound method with a chloroform/methanol mixture and small particle size. In the second step, the volatile compounds were extracted from the delipidated protein powder by the SAFE extraction method and by the HS-SPME method, and were further analysed by GC–MS. The chloroform/methanol mixture and the ultrasound method extracted a wide range of volatile compounds very efficiently. Moreover, whatever method was used to extract the lipids, the volatile compounds detected in the headspace of the delipidated powder represented less than ¼ of the volatile compounds detected in the headspace of the regular powder.     

Changes in volatile flavor compounds in steam-dried <Emphasis Type="Italic">Allium hookeri</Emphasis> root

This study was carried out to identify volatile flavor compounds in Allium hookeri root (AHR) and steam-dried AHR. The volatile compounds were extracted using a simultaneous steam distillation and extraction (SDE) method and identified by gas chromatography/mass spectrometry (GC/MS) analysis. Forty volatile compounds, present at a concentration of 76.10 mg/kg, were identified in AHR, with sulfur-containing compounds (96.8%) as the major volatile compounds. On the other hand, in two and four times steam-dried AHR, 34 volatile compounds present at 5.96 mg/kg and 28 compounds present at 4.23mg/kg were identified, respectively. This two and four times steam-dried AHR respectively contained sulfur-containing compounds (64.1 and 37.4%) and aldehydes (19.3 and 45.4%) as the dominant compounds. The sulfur-containing compounds decreased, whereas the aldehydes increased relative to levels in AHR with increased steam-drying time. This is the first report on volatile flavor compounds in AHR and steam-dried AHR.     

Analysis of volatile compounds of Antrodia camphorata in submerged culture using headspace solid-phase microextraction

In this work a headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) and GC–olfactometry (GC–O) was developed to evaluate the profile of the volatile compounds that contribute to the aroma of Antrodia camphorata in submerged culture. For this purpose, the HS-SPME sampling method for the volatile compounds of A. camphorata in submerged culture was optimised by a D-optimal design. A HS extraction of the culture broth of A. camphorata followed by incubation on a carboxen/polydimethylsiloxane (CAR/PDMS) fibre during 31.8 min at 54.6 °C gave the most effective and accurate extraction of the volatile compounds. By the optimised method, a total of 49 volatile compounds were identified in culture broth of A. camphorata, while a total of 55 volatile compounds were identified in the mycelia. A series of C₈ aliphatic compounds (mushroom-like odour), several lactones (fruity odour) and l-linalool (citrus-like odour) were the most potent key odourant in both the mycelia and culture broth. This combined technique is fast, simple, sensitive, inexpensive and useful to monitor volatile compounds associated to A. camphorata.     

Optimization of a HS-SPME-GC-MS Procedure for Beer Volatile Profiling Using Response Surface Methodology: Application to Follow Aroma Stability of Beers Under Different Storage Conditions

The optimization of the main experimental variables, such as extraction temperature, volume of sample and the extraction time of an HS-SPME/GC-MS procedure, for profiling beer volatile analysis was evaluated using response surface methodology. A central composite circumscribed design was employed to study the effect of the experimental variables on the extraction of 28 representative volatile compounds of beer flavour profile. The parameters of the models were estimated by multiple linear regressions. The strongest influence in the volatile extraction yield was the volume of the sample (V) and the extraction temperature (T), with a positive and a negative effect, respectively. The performance characteristics of the optimised method were also determined, showing adequate linear ranges, repeatability, detection and quantification limits. The optimised methodology was applied to the same beer sample stored during 5?months at three different temperature conditions (4, 20 and 40?°C). Sampling was performed monthly, and the results showed that the concentration of most volatile compounds decreased during beer storage, although the rate of decrease was clearly higher at room temperature (20?°C) compared with refrigeration conditions (4?°C). Accelerated ageing conditions (40?°C) showed the most different volatile profile. Sensory analysis also revealed large differences in the overall quality of the samples, showing that even at room temperature the aroma profile of beer is greatly modified during its shelf life.     

Headspace In-Tube Microextraction Coupled with Capillary Electrophoresis for Detection of Bromophenols in Water and <Emphasis Type="Italic">Trachypenaeus curvirostris</Emphasis>

A rapid, simple, and sensitive method has been developed for the analysis of bromophenols in tap water and Trachypenaeus curvirostris by using headspace in-tube microextraction (HS-ITME) coupled with capillary electrophoresis (CE). In the newly developed method, simply by placing a capillary filled with a basic run buffer in the HS above an acidic donor solution, volatile acidic analytes were extracted into the acceptor phase in the capillary. After extraction, electrophoresis of the extracts in the capillary was carried out. Extraction parameters such as the extraction temperature, extraction time, pH of the sample solution, ionic strength, and volume of the sample solution were systematically investigated. Under the optimized conditions, enrichment factors for three bromophenols were 812, 685, and 568, respectively. The proposed method provided a good linearity, low limits of detection (below 5.25 ng/mL), and good repeatability of the extractions (RSDs below 7.8 %, n?=?6). The tap water and T. curvirostris samples were analyzed by the proposed method, and the obtained results indicated that the proposed method provides acceptable recoveries and precisions.     

Characterisation of the volatile profile of orange juice contaminated with Alicyclobacillus acidoterrestris

A rapid and reliable analytical method, based on the characterisation of the volatile profile by dynamic headspace extraction followed by gas chromatography mass–spectrometry, was developed in order to early detect Alicyclobacillus acidoterrestris spoilage in orange juice. Gas chromatographic peak areas were submitted to multivariate statistical analysis (principal component and linear discriminant analysis) in order to visualise clusters within samples and to detect the volatile compounds able to differentiate contaminated from not-contaminated samples. Significant differences in the volatile profile of the analysed samples were found, assessing the reliability of the proposed method to detect the A. acidoterrestris contamination in orange juice.     

Ascending bubble extraction of terpenes from freshly squeezed orange juice

Terpene hydrocarbons are volatile compounds that cause aromatic deterioration of orange juice during prolonged storage. In this study, we attempted to remove terpene hydrocarbons from the freshly squeezed orange juice using an ascending bubble extraction that allowed the bubbles of nitrogen at atmospheric pressure to pass through the juice. Remaining percentages of volatile concentrations were determined by gas chromatography. d-Limonene was used as a representative of terpene hydrocarbons because of its abundance. Linalool, octanal and decanal which are necessary volatiles for orange juice were also determined the remaining percentages. The ascending bubble extraction was the effective method for removing terpene hydrocarbons from the orange juice. The concentration of d-limonene was reduced as the increases of treatment time and temperature. After the extraction at 40 °C for 60 min, d-limonene was thoroughly removed from the orange juice while linalool and decanal remained approximately 80% and 45%, respectively.     

Optimization of summer truffle aroma analysis by SPME: Comparison of extraction with different polarity fibres

The objective of the present investigation was the optimization of the extraction of volatile compounds of the summer truffle aroma (Tuber aestivum) by headspace solid-phase microextraction (HS-SPME) using fibres of different polarity able to provide complementary information. A response surface experimental design was applied considering three factors such as extraction temperature, equilibrium time and extraction time. Optimization was carried out using two fibres of different polarity (PDMS and CW/DVB) in order to obtain data about the profile of summer truffle aroma. The extracted compounds were analysed by gas chromatography with a flame ionization detector and by gas chromatography/mass spectrometry. The responses optimised were those related with the quality and intensity of the aroma such as the total area of the chromatogram. Results showed that the extraction temperature was statistically the most influential among the different factors studied; also, the polar fibre was able to extract higher amounts of total volatile compounds.     

Study of methods for the extraction of volatile compounds from fermented grape must

The main objective of the present study was to analyze the volatile compounds extracted from fermented grape musts by two extraction methods in order to characterize the samples. The purge and trap system provided the necessary sensitivity for the analysis of low-boiling point compounds, such as acetaldehyde and ethyl acetate, and the liquid–liquid extraction method allowed for the analysis of a great number of medium to high boiling point volatile compounds, such as phenylethyl alcohol, hexanoic and octanoic acids, ethyl hexanoate and ethyl octanoate. Ethyl propionate and propyl acetate, extracted by the liquid–liquid method, characterized the sample of grape must fermented by Kloeckera apiculata. The sample of grape must fermented by Pichia membranaefaciens was characterized by 2-propanol and 2-hexanone, extracted by the purge and trap system and liquid–liquid method, respectively. These results show that the purge and trap/dynamic headspace system and liquid–liquid extraction method are complementary in the determination of the aroma profiles of fermented grape musts and characterization of the samples.     

Volatile compounds of copoazú (Theobroma grandiflorum Schumann) fruit

Volatile compounds were isolated from copoazú (Theobroma grandiflorum Schumann) fruit by liquid–liquid extraction at two different pH values of 3.3 (natural) and 7. The volatile extracts were analyzed by capillary GC–FID and GC–MS. Among the 56 compounds identified at two pH values, many of them were only present in the lower pH extract, confirming the presence of bound compounds in copoazú. Ethyl butanoate, ethyl hexanoate and linalool were the major constituents found in copoazú fruit.     

Antioxidant Activities of the Supercritical and Conventional Satureja montana Extracts

ABSTRACT:  The antioxidant activities of the volatile and the nonvolatile fractions from  Satureja montana  obtained by supercritical fluid extraction (SFE) and by conventional techniques, hydrodistillation (HD) and soxhlet extraction (SE), were compared. A good agreement between DPPH and rancimat methods was obtained showing that the extracts were able to scavenge free radicals and to inhibit lipid oxidation. The volatile oil (obtained by SFE at 90 bar/40 °C) was the most effective extract, presenting the lowest EC₅₀ (0.06 g/L) and the highest protector factor (PF = 2.03). These results demonstrated the advantages of SFE over conventional techniques by avoiding thermodegradation and hydrolysis reactions. Furthermore, volatile oil is 15 times richer in thymoquinone than the essential oil (HD). This compound is of great importance due to its antioxidant, neuroprotective, and anti-cancer activities. The combination of carvacrol + thymol + thymoquinone in volatile oil may be responsible for the increase in the antioxidant activity when compared to HD, which demonstrates that, in this case, SFE improves value to the final product.     

Comparison of Two Extraction Techniques,Solid‐Phase Microextraction Versus Continuous Liquid–Liquid Extraction/Solvent‐Assisted Flavor Evaporation,for the Analysis of Flavor Compounds in Gueuze Lambic Beer

Lambic is a beer style that undergoes spontaneous fermentation and is traditionally produced in the Payottenland region of Belgium, a valley on the Senne River west of Brussels. This region appears to have the perfect combination of airborne microorganisms required for lambic's spontaneous fermentation. Gueuze lambic is a substyle of lambic that is made by mixing young (approximately 1 year) and old (approximately 2 to 3 years) lambics with subsequent bottle conditioning. We compared 2 extraction techniques, solid‐phase microextraction (SPME) and continuous liquid–liquid extraction/solvent‐assisted flavor evaporation (CCLE/SAFE), for the isolation of volatile compounds in commercially produced gueuze lambic beer. Fifty‐four volatile compounds were identified and could be divided into acids (14), alcohols (12), aldehydes (3), esters (20), phenols (3), and miscellaneous (2). SPME extracted a total of 40 volatile compounds, whereas CLLE/SAFE extracted 36 volatile compounds. CLLE/SAFE extracted a greater number of acids than SPME, whereas SPME was able to isolate a greater number of esters. Neither extraction technique proved to be clearly superior and both extraction methods can be utilized for the isolation of volatile compounds found in gueuze lambic beer.     

HS‐SPME/GC‐MS and chemometrics for volatile composition of Chinese traditional aromatic vinegar in the Zhenjiang region

The main purpose of this study was to determine the volatile composition of Zhenjiang aromatic vinegar, one of the four famous China‐style cereal vinegars, by using headspace solid‐phase microextraction (HS‐SPME)/gas chromatography‐mass spectrum (GC‐MS) and chemometrics. For this purpose, the HS‐SPME sampling method for the volatile compounds of Zhenjiang aromatic vinegar was optimized by a second‐order rotatable central composite experimental design (CCD). A HS extraction of the volatile compounds by incubation on a 65 µm thickness polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre during 44.2 min at 69.5°C with 1.9 g NaCl add gave the most effective and accurate extraction. By the optimized method, a total of 58 volatile compounds, including 9 alcohols, 13 acids, 16 esters, 5 aldehydes, 4 ketones and 8 heterocycle compounds, were identified from 13 aromatic vinegar samples manufactured in Zhenjiang region. By principal components analysis (PCA), the thirteen vinegar samples were classified into 3 groups, and 10 volatile compounds were chosen as characteristic compounds of Zhenjiang aromatic vinegars. Copyright © 2012 The Institute of Brewing & Distilling     

Volatile Constituents of Jambolan (<Emphasis Type="Italic">Syzygium cumini</Emphasis> L.) Fruits at Three Maturation Stages and Optimization of HS-SPME GC-MS Method Using a Central Composite Design

The volatile compounds of jambolan (Syzygium cumini L.) fruit were determined at three different maturity stages (unripe, half-ripe, and ripe) by headspace solid-phase microextraction (HS-SPME)–gas chromatography-mass spectrometry (GC-MS) technique using five different fibers (Fused silica PDMS/DVB, DVB/CAR/PDMS, PEG, Stable flex PDMS/DVB, and PDMS). The optimal extraction conditions were evaluated using different variables such as adsorption temperature (minimum 25 °C, maximum 55 °C), salt quantity (minimum 0, maximum 30.0%), and extraction time (min 10, max 30 min). The major classes of compounds identified were ester, terpene, alcohol, aldehyde, and carboxylic acid. Ninety volatile compounds with characteristics aroma attributes were identified, and the primary compounds linked with development of characteristics aroma of ripe jambolan fruit pulp were trans-β-ocimene, β-ocimene, caryophyllene, humulene, D-α-pinene, L-β-pinene, β-pinene, D-limonene, α-terpineol, neo-allo-ocimene, 2-hexenal (E), δ-cadinene, 3-hexen-1-ol, (Z) β-linalool, terpinolene, eremophilene, valencene, 1-hexanol, longipinene, γ-terpinene, γ-muurolene, endo-borneol, o-cymene, nonanal, terpinen-4-ol, β-terpineol, α-muurolene, fenchol, α-fenchene, β-thujene, benzaldehyde, (E)-2-hexenal, β-cadinene, and decanal.     

HS-SPME coupled to GC/MS for quality control of Juniperus communis L. berries used for gin aromatization

HS-SPME coupled to GC/MS was applied to the analysis of the volatile fraction of Juniperus communis L. berries, which are the principal ingredient used for gin aromatization. Seventy seven compounds were identified by comparison with reference compounds or tentatively identified by comparing their mass spectra and retention index with those reported in mass spectra libraries and literature, respectively. Seventy four were detected by SPME and sixty eight were detected by solvent distillation extraction (SDE). These were mainly mono- and sesquiterpenic compounds that represented more than the 80% of the gin’s volatile composition. A high percent content was due to monoterpenoids, whose analysis could be important for the assessment of sensory quality control of juniper due to their impact on gin aroma. The main monoterpenoids detected in the headspace of the juniper berries from two periods of collection were terpinen-4-ol, p-cymene, β-myrcene, γ-terpinene, α-pinene and limonene. These represented more than the 70% of the sample’s volatile fraction. The proposed SPME method required short times and the low cost of analysis and enabled to detect a number of compounds comparable with SDE or much higher than the number of compounds reported by other extraction techniques. The results suggested the suitability of this technique for the assessment of the volatile composition of juniper berries intended for gin flavouring.     

Comparative study of free and glycoconjugated volatile compounds of three banana cultivars from French West Indies: Cavendish,Frayssinette and Plantain

Free and glycoconjugated volatile composition of three bananas from cultivars of Musa sp. grown in the French West Indies (FWI): Cavendish, Frayssinette and Plantain were investigated. They were extracted from the pulp of bananas thanks to an accelerated solvent extraction method for the free volatile compounds. Glycosides were isolated from aqueous extracts then aglycons were obtained after enzymatic hydrolysis of glycosidic extracts. Free volatile compounds and aglycons were analysed by GC–MS. The main volatile compounds found in Cavendish banana were (E)-2-hexenal and acetoin, in Plantain: (E)-2-hexenal and hexanal, and in Frayssinette: 2,3-butanediol and two diastereomer solerols. The most abundant of aglycons were 3-methyl-butanol, 3-methyl-butanoic acid, solerol (two disatereoisomers) and acetovanillone. This compound, rarely identified in fruits, is detected for the first time in glycoconjugated volatile compounds of fruits. The abundance of these two isomers in the extracts of Frayssinette seemed to be characteristic of this variety of banana.     

Establishment of Monstera deliciosa fruit volatile metabolomic profile at different ripening stages using solid-phase microextraction combined with gas chromatography–mass spectrometry

The volatile metabolomic profile of Monstera deliciosa fruits (M. deliciosa, ceriman) at three ripening stages, ripe, half-ripe and unripe, was established using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography–quadrupole mass spectrometry detection (GC–qMS). To obtain the optimal HS-SPME conditions, the main experimental parameters that influence the extraction efficiency and experimental response were analyzed. The highest extraction efficiency was achieved with 1 g of ceriman sample, using a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber for 60 min at 40 °C with 15% NaCl (w/w). After optimization, all ceriman samples were analyzed with the best extraction conditions that allowed to identify 80 volatile metabolites (VOMs), belonging to different chemical groups namely ethyl esters (88.61–77.94%), terpenoids (18.08–9.83%), carbonyl compounds (3.41–1.05%), higher alcohols (1.41–0.51%) and lactones (0.14–0.03%). Thirty-eight of the identified volatile metabolites (47.50%) have not been reported in M. deliciosa, so far, providing a more complete characterization of its volatile composition. The predominant VOMs identified in M. deliciosa fruits were ethyl butanoate, linalool, ethyl hexanoate, ethyl 2-methyl butanoate, butanoic acid, ethyl benzoate and propyl butanoate. Remarkable differences were found in both the quantitative and qualitative composition of M. deliciosa fruits at different ripening stages.Principal component analysis (PCA) provided a suitable tool to differentiate the volatile profile of target fruits among three ripening stages.     

Volatile profile and potential of inactive dry yeast‐based winemaking additives to modify the volatile composition of wines

BACKGROUND: With the objective of determining the potential of winemaking additives based on inactive dry yeast (IDY) to modify the volatile composition of wines, gas chromatography coupled to mass spectrometry was employed to characterize the volatile profile of a widely used IDY preparation. To have the most accurate picture of the volatile compounds, pressurized liquid extraction technique (PLE) was used with different solvents and extraction temperatures. Complementary headspace solid‐phase microextraction was applied to gain insight into the volatile composition. In addition, the ability of some target volatile (pyrazines) to be released into model wines was investigated. RESULTS: The PLE technique was mainly suitable for the extraction of volatile compounds with a low to medium molecular weight and the best extraction yields were obtained by using apolar solvents (hexane) and high temperatures (150 °C). PLE in combination with solid‐phase microextraction allowed the identification of 35 volatile compounds, most of them heterocyclic‐containing nitrogen compounds formed during the processing of IDY that could be released into the wines: the signal of four target masses corresponding to 2,5‐dimethylpyrazine, trimethylpyrazine, methylbutylpyrazine and 2‐ethyl‐3,5‐dimethylpyrazine increased in the synthetic wines after 13 days when IDY was left in the model wines. CONCLUSION: The study confirmed that some volatile compounds identified in IDY which were formed during processing could be released into the wines which might modify wine aroma composition. Copyright © 2009 Society of Chemical Industry