Analysis and characterization of aroma‐active compounds of Schizandra chinensis (omija) leaves

Volatile components from leaves of Schizandra chinensis (omija), a native plant of Korea, were extracted by simultaneous distillation–extraction (SDE) and analyzed by gas chromatography–mass spectrometry (GC‐MS) using two types of capillary column with different polarities (DB‐5MS and DB‐Wax). The GC‐MS analysis of volatile compounds obtained by SDE revealed that germacrene D is the most abundant compound (22.6%) in omija leaves, followed by β‐elemene (17.4%), (E)‐2‐hexenal (8.7%), and (E)‐β‐ocimene (7.2%). Aroma‐active compounds were determined by gas chromatography–olfactometry (GC‐O) using the aroma‐extract‐dilution analysis method. (E,Z)‐2,6‐Nonadienal (cucumber) was the most intense aroma‐active compound due to its higher flavor‐dilution factor (243–729) than any other compound. (Z)‐3‐Hexenal (green/apple), (E)‐2‐hexenal (green/fruity), and (E)‐β‐ocimene (wither green/grass) were also identified as important aroma‐active compounds by GC‐O. In addition, the volatile compounds were extracted by solid‐phase microextraction (SPME), and the quantitative analysis of the SPME samples gave slightly different results, depending on the type of SPME fiber, compared with those from SDE, However, the aroma‐active compounds identified in SPME were similar to those in SDE. Copyright © 2004 Society of Chemical Industry     

Enhancement of volatile aromatic compounds in black raspberry wines via enzymatic treatment

Robus coreanus Miquel is widely used in the production of Korean black raspberry (KBR) wine owing to its health benefits and commercial value. The effects of three different commercially available glycosidase enzymes on the volatile compounds in KBR wines were investigated with large‐scale fermentation to develop a high‐flavour‐quality wine. Volatile aroma compounds from the wines were analysed using headspace‐solid phase micro‐extraction‐gas chromatography–mass spectrometry (HS‐SPME‐GC–MS) and sensory evaluations were performed to evaluate the flavour characteristics. KBR wines treated with commercial enzymes yielded high concentrations of terpenes and esters compared with the control wine because the odourless non‐volatile glycosides in KBR wines were converted to their corresponding free forms by the enzymes. HS‐SPME‐GC–MS‐SIM analysis showed that the primary monoterpene compounds in KBR wines treated by the enzymes were myrtenol, linalool, citronellol and a significant quantity of compounds such as 2‐phenyl ethanol and ethyl benzoate, which contributed to the flavour of KBR wine, as determined by GC‐FID. KBR wines treated with the enzymes exhibited different sensory characteristics from the control wine owing to higher intensity of floral and fruity aromas. KBR wine treated with CYTOLASE PCL5 on a large scale exhibited the highest sensory preference. Copyright © 2017 The Institute of Brewing & Distilling     

Chemotaxonomical analysis of the essential oil aroma compounds of four different<Emphasis Type="Italic"> Ocimum</Emphasis> species from southern India

The essential oil aroma compounds of four different Ocimum species ( O. americanum, O. basilicum, O. gratissimum and O. sanctum) from southern India were analysed by solid phase microextraction (SPME)/gas chromatography (GC)/flame ionization detection (FID), SPME/GC/mass spectrometry (MS) and olfactoric evaluations. The essential oil of the whole plant of O. americanum is rich in ( E)-methyl cinnamate (72.05%), ( Z)-methyl cinnamate (9.11%), camphor (5.95%) and ß-selinene (3.43%); the essential leaf oil of O. basilicum contains ( E)-methyl cinnamate (34.49%), linalool (28.44%), camphor (13.08%), ( Z)-methyl cinnamate (6.90%) and geraniol (3.84%), whereas the essential leaf oil of O. gratissimum comprises eugenol (63.36%), ( Z)-ß-ocimene (9.11%), germacrene D (8.84%) and ß-caryophyllene (3.89%). Finally, the essential leaf oil of O. sanctum shows methyl eugenol (56.18%), ß-caryophyllene (16.60%) and germacrene D (5.10%) as main constituents. Therefore, the following chemotypes can be attributed to the analysed Ocimum samples: O. americanum, methyl cinnamate-type; O. basilicum, methyl cinnamate/linalool-type; O. gratissimum, eugenol-type; and O. sanctum, methyl eugenol-type. The character impact compounds of the essential oils of the four investigated Ocimum samples, as well as a discussion of their possible use in food products, is also given.     

Determination of volatile compounds to characterize fish spoilage using headspace/mass spectrometry and solid‐phase microextraction/gas chromatography/mass spectrometry

Changes in volatile compounds were monitored in whiting (Merlangius merlangus), cod (Gadus morhua) and mackerel (Scomber scombrus) and related to spoilage. Data are presented from headspace/mass spectrometric (HS/MS) analysis and solid‐phase microextraction/gas chromatographic/mass spectrometric (SPME/GC/MS) analysis at two time points (day 0 and day 10) during storage at 4 °C. HS/MS revealed 24 ions that could be used as markers of spoilage. SPME/GC/MS identified 86 compounds, 20 of which could perhaps be used to characterize freshness: principally alcohols, ketones, aldehydes and C₂–C₁₁ esters. Compounds common to the three species studied appear to be generated by microbial degradation. Copyright © 2005 Society of Chemical Industry     

Odour gradients and patterns in volatile emission of different plant parts and developing fruits of grapefruit (Citrus paradisi L.)

The volatiles spontaneously emitted in vivo by different plant parts of grapefruit (Citrus paradisi Macf., Rutaceae) were collected by solid phase micro-extraction (SPME) during the whole vegetative cycle of the plant and characterised by GC–MS to verify their involvement in entomophilous pollination, a controversial topic in the biology of this species. Furthermore, the essential oils obtained by expression of the pericarp from unripe and ripe fruits were studied. Altogether 127 compounds were identified, accounting from 82.1% to 99.9% of the whole volatiles. The main constituents detected were mono- and sesquiterpenes, with limonene (0.5–95.2%), linalool (0.2–52.5%), sabinene (0.5–42.5%), myrcene (0.2–15.4%), and β-caryophyllene (0.3–41.0%) as the most represented ones.     

Characterization of Aroma Compounds in Chinese Bayberry (Myrica rubra Sieb. et Zucc.) by Gas Chromatography Mass Spectrometry (GC‐MS) and Olfactometry (GC‐O)

Abstract: The aroma‐active compounds in Chinese bayberry were identified using gas chromatography‐olfactometry (GC‐O) and GC‐mass spectrometry techniques. The volatile compounds were extracted using Liquid–liquid extraction, solvent‐assisted flavor evaporation and headspace solid‐phase microextraction (HS‐SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4‐terpineol, linalool oxide, linalool, benzyl alcohol, α‐methylbenzyl alcohol, β‐phenylethanol, 3‐methylbutanoic acid and acetic acid, and so on. Moreover, HS‐SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, β‐caryophyllene) was predominant and its concentration represented over 89.9% of the overall compounds, and alcohols, aldehydes, ketones, esters, acids, and others were typically present in lesser amounts. Finally, principal component analysis revealed that there was also significant difference between immature and mature waxberry fruits     

The sesquiterpene composition of leaf cuticular neutral lipids of ten Polish varieties of Solanum tuberosum

The sesquiterpene composition of leaf cuticular neutral lipids of potato (Solanum tuberosum) varieties was investigated by GC, GC-MS and HPLC. The distribution of sesquiterpenes varied between varieties with the major components being β-caryophyllene, trans-β-farnesene, germacrene D, β-sesquiphellandrene and germacrene D-4-ol. cis-β-Farnesene and bicyclogermacrene were identified in potato for the first time. The amount of sesquiterpenes was 10–60% of the cuticular neutral lipids depending on variety. The sesquiterpenes and alkanes were the major groups of components in the waxes investigated. © 1998 SCI.     

Characterization of volatile compounds in Criollo,Forastero, and Trinitario cocoa seeds (Theobroma cacao L.) in China

The volatile composition of cocoa from 16 accessions covering three different morphogenetic groups, namely, Criollo, Forastero, and Trinitario, was investigated. Fifty-three compounds were profiled using HS-SPME-GC-MS, and the number of volatiles per accession was found to be significantly associated with the morphogenetic groups. Volatile assemblages differed significantly among Criollo, Forastero, and Trinitario groups (ANOSIM, R = 0.715, p = 0.001). The differences in the volatile compounds of the three morphogenetic groups were essentially quantitative, and only a few compounds were found exclusively specific to a certain group, mainly in Trinitario. Moreover, the volatile compounds differed from these morphogenetic groups, which revealed complex interactions between them, including participation in the same biosynthetic pathways. Principal component analysis revealed that Trinitario cocoa had high contents of furfuryl alcohol, 3-carene, 2-pentanol, 1-pentanol, 2,3-butanediol, 2-heptanol, and benzyl acetate. Criollo cocoa contained high amounts of α-limonene, β-caryophyllene, β-myrcene, α-phellandrene, β-linalool, and acetic acid. Forastero cocoa also exhibited high contents of 3-methylbutanoic acid, 2-(2-butoxyethoxy) ethanol, anethole, and 2,4-pentanediol. However, the volatile compound pattern detected in Forastero cocoa was inconsistent. Volatile profiling of cocoa by HS-SPME-GC-MS and the interrelationship detected among the volatiles can be used as a roadmap for future breeding or biotechnological applications.     

我国主要金柑品种果皮中挥发性成分比较

基于顶空固相微萃取-气相色谱-质谱联用技术,比较我国15 个金柑品种果皮中主要挥发性物质的种类和含量差异。15 个金柑品种累计检出195 种挥发性物质,各品种果皮检出组分数变幅为45～78;总含量变化幅度为791.69～27 405.95 μg/g,变异系数为46.46%;包括烃类、醇类、醛类、酮类和酯类;主要成分为柠檬烯、月桂烯、松油烯、萜品烯、异柠檬烯、异松油烯、左旋-α-蒎烯、γ-榄香烯、丁香烯、吉马烯、α-紫穗槐烯、芳樟醇等物质,不同金柑品种间累计特有成分55 种。利用R软件数据统计结合主成分分析,基于挥发性物质对金柑品种进行了统计学分析,结果显示我国金柑挥发性物质种类和含量丰富,差异显著,可以作为区分不同金柑的辅助工具。     

Changes in volatile aroma compounds of pineapple (Ananas comosus) during freezing and thawing

Changes in the volatile aroma compounds of pineapple (Ananas comosus) during freezing and thawing were compared against fresh samples to determine the effect of freezing on pineapple flavour. An HS‐SPME–GC–MS analysis showed that the Smooth Cayenne pineapple variety had nineteen volatile compounds, in four classes of compounds including fourteen esters, two hydrocarbons, two sulphur‐containing compounds and one lactone. The main characteristic volatile compounds of the fresh pineapple were methyl hexanoate, ethyl hexanoate, ethyl 3‐methylthiopropanoate and 1‐(E,Z)‐3,5‐undecatriene. Freeze–thaw cycles were associated with the loss of some volatile aroma compounds, particularly the esters which were found to be the main characteristic of fresh pineapples. The freezing and thawing process was found to cause damage to the pineapple tissues due to ice recrystallisation and dehydration which lead to the reduction of volatile aroma compounds.     

Characterization of volatile compounds in Fen‐Daqu – a traditional Chinese liquor fermentation starter

Fen‐Daqu is a saccharifying agent and fermentation starter for the production of Chinese liquor Fen (alcoholic spirit) and Fen traditional vinegar. The volatile compounds produced at seven incubation steps were analysed by HS‐SPME‐GC‐MS. A total of 83 major volatile compounds were identified, including 23 esters, 8 acids, 24 alcohols, 18 ketones and aldehydes, 6 pyrazines and 4 acetals. Data obtained by HS‐SPME‐GC‐MS were subjected to principal component analysis. The trajectory plots of volatile compounds in Fen‐Daqu samples obtained during successive steps of incubation were revealed. The major compounds that contributed to discrimination were hexanal, (E)‐2‐octenal, (Z)‐2‐octen‐1‐ol, nonanoic acid, 1‐octanol, 2‐decen‐1‐ol, hexyl acetate, (E)‐2‐octen‐1‐ol, acetic acid, ethyl acetate, phenylethyl alcohol, ethyl alcohol, octanoic acid, 1‐octanol, 3‐methyl‐2‐buten‐1‐ol and pyrazines. Copyright © 2012 The Institute of Brewing & Distilling     

Changes in the hop-derived volatile profile upon lab scale boiling

Hop terpenes might be oxidized during kettle boiling into more water soluble compounds that could contribute to ‘hoppy’ aroma of kettle hopped lager beers. Our current research proves that the boiling process induces significant changes in the hop oil volatile profile. The discrimination between volatile profiles of unboiled and boiled hop essential oil was evaluated via principal component and cluster analysis (PCA and CA). HS–SPME–GC–MS analysis revealed quantitative changes (e.g. increases in the levels of oxygenated α-humulene and β-caryophyllene derivatives) as well as qualitative changes (i.e. detection of compounds, not found in unboiled hop essential oil) in the hop oil volatile profile upon boiling. Many of these compounds were previously found in lager beer and may therefore contribute to beer flavor. Interestingly, the analytical difference between unboiled and boiled hop essential oil proved to be more pronounced as the initial hop essential oil concentration used for boiling was increased. In addition, lager beers spiked with boiled hop oil were described as ‘hoppy/spicy’ during sensory evaluations. Therefore, the newly formed products and hop oil constituents that are characterized by an increased recovery after boiling, are candidate compounds for ‘hoppy’ aroma in real brewing practice.     

Essential oil of Teucrium scorodonia L. ssp. scorodonia from Italy

The essential oil of the flowering aerial parts of Teucrium scorodonia L. ssp. scorodonia growing in Italy on Verrucano, was analyzed by GC and GC–MS. All the identified compounds were sesquiterpene hydrocarbons. The main ones were germacrene B (26.2%) and β-caryophyllene (25.2%).     

COMPARISON OF HEADSPACE SOLID PHASE MICROEXTRACTION AND XAD-2 METHODS TO EXTRACT VOLATILE COMPOUNDS PRODUCED BY SACCHAROMYCES DURING WINE FERMENTATIONS

A modified headspace solid phase microextraction (HS‐SPME) method was compared with Amberlite® XAD‐2 resin for the extraction of volatile compounds. In the HS‐SPME method, volatiles were extracted using an 85 μm polyacrylate fiber from wines that contained a standardized amount of ethanol (10% v/v), NaCl (0.325 g/mL) and internal standards (dodecanol and nonanoic acid). Both extraction procedures yielded high relative recoveries (>92%) and reproducibilities (coefficient of variations ≤ 11%) for the different higher alcohols, esters and medium‐chain fatty acids. Overall, limits of detection for the HS‐SPME and XAD‐2 methods were below sensory threshold concentrations. HS‐SPME and XAD‐2 performed similarly in the analysis of a Riesling wine; however, the HS‐SPME method did not require organic solvents and was generally quicker to perform. In applying the HS‐SPME method, differences in concentrations of volatile compounds produced in Riesling and Chenin blanc wines by 11 different yeast strains were noted.     

Effects of different deodorising processes on the off‐odour compounds and gel properties of common carp surimi

In order to improve the utilisation of the common carp (Cyprinus carpio), the effects of deodorising agents [NaCl, β‐CD, malic acid (MA) and hawthorn extract (HE)] on the volatile compounds of common carp mince and its surimi gel properties were investigated. In total, thirty‐two volatile compounds were identified, seven of which were considered the main compounds of off‐odour, using HS‐SPME‐GC‐MS and OVA analyses. HS‐SPME‐GC‐MS analysis showed that MA and HE removed 84.51% and 77.18% off‐odour compounds, respectively. Three relaxation components (T₂₁, T₂₂, T₂₃) were found in surimi, and their amounts were not affected by deodorising; however, the relaxation time of major component T₂₂ was significantly increased. Surimi deodorised by HE had the highest gel strength because of its increased breaking displacement; however, a slight decrease in whiteness was observed. Thus, appropriate levels of HE could improve the palatability of surimi.     

Odour‐active compounds in mango (Mangifera indica L. cv. Corazón)

Simultaneous distillation–extraction combined with GC‐FID and GC‐MS were used to analyse volatile compounds from mango (Mangifera indica L. cv. Corazón) and to estimate the most odour‐active compounds in the fruit. The analyses led to the identification of 167 components, from which 128 were positively identified. The aroma‐active areas in the gas chromatogram were screened by the application of the aroma extract dilution analysis and by odour activity values. Eighteen odorants were considered as the most odour‐active compounds: (E)‐β‐damascenone, ethyl butanoate, (E,Z)‐nonadienal, ethyl 2‐methylpropanoate, (E)‐2‐nonenal, (E)‐β‐ionone, terpinolene, δ‐3‐carene, β‐caryophyllene, ethyl 2‐methylbutanoate, limonene, myrcene, linalool, γ‐octalactone, nonanal, methyl benzoate, 2,5‐dimethyl‐4‐methoxy‐3(2H)‐furanone and hexanal.     

In vitro degradation by mixed rumen bacteria of 17 mono‐ and sesquiterpenes typical of winter and spring diets of goats on Basilitica rangelands (southern Italy)

BACKGROUND: Nine monoterpenes (δ‐3‐carene, p‐cymene, limonene, β‐myrcene, (E)‐ and (Z)‐β‐ocimene, α‐phellandrene, α‐terpinene, γ‐terpinene), seven oxygenated monoterpenes (1,8‐cineole, linalool, (E)‐ and (Z)‐linalool oxide, 4‐terpinenol, α‐terpineol, α‐terpinolene) and one sesquiterpene (β‐cedrene) were investigated for their degradability in the rumen microbial ecosystem. These molecules were identified as dominant terpenes in the winter and spring diets of milking goats in Basilicata (southern Italy). RESULTS: All terpenes were tested at 3.33 µL L^?1 for 24 h using in vitro incubation with mixed rumen bacteria from dairy goats. Oxygen‐containing compounds were those recovered at the highest levels (89% of (E)‐linalool oxide, 93% of (Z)‐linalool oxide, 91% of 1,8‐cineole, 82% of terpineol and 72% of 4‐terpinenol), except linalool. The linear alkenes β‐myrcene and β‐ocimene almost completely disappeared. Results were more variable among cyclic alkenes, with recovery rates ranging from 50% in the case of limonene to less than 1% for α‐phellandrene. 17% of the only sesquiterpene of the group, β‐cedrene, was recovered. CONCLUSION: Recovery rates differed markedly among terpenes, partly in relation to the presence of oxygen and rings in the molecules. These observations should contribute to a better understanding of the changes in composition between the diet and milk terpenes. Copyright © 2008 Society of Chemical Industry     

Determination of flavour compounds in beer using stir‐bar sorptive extraction and solid‐phase microextraction

The analysis of volatile compounds in beer is important for quality control in the brewing industry. In this study, stir‐bar sorptive extraction (SBSE) and solid‐phase microextraction (SPME), two solvent‐less enrichment techniques, were applied in combination with gas chromatography flame ionization detection (GC/FID) for the determination of four flavour compounds (isoamyl acetate, ethyl hexanoate, benzaldehyde, myrcene) in beer. Limits of detection, linearity and repeatability of both methods were determined using standard ethanol solutions, while accuracy was determined by conducting recovery tests on commercial beer samples. Both methods were characterized by high linearity (r > 0.996) and repeatability (RSD = 1.76–10.66%). When both methods were compared, higher recoveries were obtained by SBSE, with limits of detection 1.8–2.8 times lower compared with SPME. In the analysis of commercial beer samples using both methods, SBSE analysis resulted in higher recoveries, therefore demonstrating promise for the analysis of beer volatiles. Copyright © 2015 The Institute of Brewing & Distilling     

Antifungal property of the essential oils and their constituents from Cinnamomum osmophloeum leaf against tree pathogenic fungi

This study compares the chemical constituents of leaf essential oils from various geographical provenances of Cinnamomum osmophloeum and investigates their antifungal activities against six tree pathogenic fungi. According to GC‐MS and cluster analyses, the leaf essential oils obtained from different geographical provenances and their relative contents were classified into six chemotypes: cinnamaldehyde type, cinnamaldehyde–cinnamyl acetate type, cinnamyl acetate type, linalool type, camphor type, and mixed type. Results from the antifungal tests show that the leaf essential oils of cinnamaldehyde type and cinnamaldehyde–cinnamyl acetate type have excellent inhibitory effect against Rhizoctonia solani, Collectotrichum gloeosporioides, Ganoderma australe and Fusarium solani. Furthermore, among the fourteen constituents of C osmophloeum leaf essential oils, Z‐cinnamaldehyde, eugenol, geraniol and citral display the best antifungal properties. Comparisons of the antifungal properties of Z‐cinnamaldehyde congeners reveal that Z‐cinnamaldehyde exhibits the best antifungal property of this group. Copyright © 2005 Society of Chemical Industry     

两种生产工艺藤椒油产品挥发性成分对比分析

采用顶空-气相色谱-质谱法对两种生产工艺藤椒油产品的挥发性成分进行分析,并结合NIST14质谱数据库检索定性,峰面积归一法定量。结果显示:传统油浸法和超临界CO₂萃取法藤椒油产品中共鉴定出33种挥发性成分,共有的挥发性成分有16种,主要的挥发性成分(相对含量≥4.5%)有4种(右旋萜二烯、芳樟醇、桧烯和月桂烯);传统油浸法特有的挥发性成分有6种(β-榄香烯、1-石竹烯、大根香叶烯、α-石竹烯、辛醛和癸醛),超临界CO₂萃取法特有的挥发性成分有11种(3-甲基-2-丁烯腈、5-氰基-1-戊烯、左旋-β-蒎烯、α-松油烯、反式-β-罗勒烯、3,3-二甲基己醇、乙酸-4-松油烯醇酯、苯乙酸甲酯、(E,E)-2,4-己二烯醛、(+)-香茅醛和1-甲基-异己酸)。烯类和醇类化合物是藤椒油产品挥发性成分的主要种类,但其相对含量存在差异;超临界CO₂萃取法藤椒油产品的挥发性成分中含有微量的酸类化合物(1-甲基-异己酸)。该研究结果可为改善生产加工工艺和提高藤椒油产品品质提供理论依据。