scholarly journals Design of the Extraction Process for Characterization of Volatile Profile of Stem Wood by Solid-Phase Microextraction

2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1984272 ◽  
Author(s):  
Tomáš Bajer ◽  
Jakub Šulc ◽  
Karel Ventura ◽  
Petra Bajerová

A method for isolation of volatile compounds from samples of stem wood by solid-phase microextraction was developed. The extraction method was optimized using a central composite design approach. Extraction temperature and extraction time were optimized in the ranges of 40°C to 120°C and 10 to 90 minutes, respectively. Final extraction method was combined with GC-MS for separation and identification of volatile components of wood samples of seven tree species, commonly occurring in Central Europe. All of them were deciduous (acacia, alder, beech, elm, larch, maple, and oak). In total 185 organic compounds were identified in volatile profiles of all the samples by the developed method. To facilitate the evaluation of the suitability of the proposed method for extraction of different compound types, all identified compounds were categorized into 16 groups. Percentage of compound groups in volatile profiles of individual wood samples shows that the developed method is suitable for evaluation of a wide range of volatile components from stem wood.

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1166
Author(s):  
Veronica Lolli ◽  
Animesh Acharjee ◽  
Donato Angelino ◽  
Michele Tassotti ◽  
Daniele Del Rio ◽  
...  

Coffee capsules market is on the rise as it allows access to a wide selection of coffee, differing in taste and brand. However, few data about the chemical characterization of the capsule-brewed coffee aroma are available. In this work, an untargeted approach using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS) and combined to chemometrics was performed to study and compare aroma profile from 65 capsule-brewed espresso coffees (ECs) commercialized by five of the most representative brands in Italy. Volatile profiles obtained from ECs were subjected to multivariate statistical analysis, which generally did not show a significant variability among coffees belonging to the same brand, except for those modified after the addition of specific flavor additives or aromatic substances (such as caramel, chocolate, etc.). Similarities may be related to the starting coffee brew or the processing method, which is likely the same for each individual brand. Additionally, partial least squares discriminant analysis (PLS-DA) showed that capsules from a specific brand contain the highest concentration of pyrazines, thus characterized by an intense and characteristic aroma, and a stronger note than those from the other brands. This study supports that the chemical analysis in conjunction with chemometric tools is a useful approach for assessing flavor quality, even if the need remains to identify volatile markers of high-quality beverages.


2020 ◽  
Vol 14 (3) ◽  
pp. 359-368
Author(s):  
Ruyi Sha ◽  
Haoan Fan ◽  
Zhenzhen Wang ◽  
Gaojian Wang ◽  
Yanli Cui ◽  
...  

A method based on solid phase microextraction coupled with gas chromatography mass spectrometry was developed for volatile profiling fermented perilla leaves jiaosu (PFJ) during fermentation. Five fibers were firstly evaluated by the total peak areas and the number of volatile compounds. Secondly, a Plackett-Burman design was applied to screen for seven independent variables selected in literature. Three significant variables (extraction time, extraction temperature and equilibrium time) were therefore selected for the following optimization studies. A Box-Behnken design combined with a steepest ascent was then used to optimize the significant factors. Under optimal conditions, the changes of volatile profiles of PFJ at 7, 14, 21, 28, 91 and 140 d were analyzed. A total of fifty-one volatile compounds were identified, and alcohols (68.12–78.94%) were the main volatile components in PFJ, followed by methoxy-phenolic compounds (4.67–5.48%). Perilla alcohol and trans-Shisool were the major constituents during spontaneous fermentation, which accounted for 16.14–30.66% and 19.95–24.52%, respectively. The results showed that PFJ fermented into a health probiotic product with characteristic flavour and functional volatile compounds.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1000
Author(s):  
Theano Mikrou ◽  
Katerina Kasimati ◽  
Ioanna Doufexi ◽  
Maria Kapsokefalou ◽  
Chrysavgi Gardeli ◽  
...  

Table olives represent one of the most important fermented products in Greece. Their highly appreciated flavor is directly associated with the volatile composition. However, extensive data on the volatile profile of table olives from Greek cultivars are scarce in the literature. For this reason, the volatile components of industrially fermented table olives from Kalamata, Conservolea and Halkidiki cultivars grown in different geographical areas within Greece were determined using headspace solid-phase microextraction combined with gas chromatography–mass spectrometry. More than 100 volatile compounds were identified and distributed over different chemical classes. All samples were rich in esters, alcohols and acids, whereas the samples of cv. Halkidiki were also characterized by increased levels of volatile phenols. Both qualitative and quantitative differences were observed, which resulted in the discrimination of the table olives according to olive cultivar and growing location. To the best of our knowledge, this is the first systematic study on the volatile profiles of table olives from Greek cultivars that also highlights the pronounced effect of olives’ growing location.


2003 ◽  
Vol 58 (11-12) ◽  
pp. 797-803 ◽  
Author(s):  
Deniz Tasdemir ◽  
Betül Demirci ◽  
Fatih Demirci ◽  
Ali A. Dönmez ◽  
K. Hüsnü Can Baser ◽  
...  

Abstract Volatile constituents of various solvent extracts (n-hexane, CH2Cl2, H2O) of 15 different organs (leaves, flowers, fruits) of five Rhododendron species (Ericaceae) growing in Turkey were trapped with headspace solid-phase microextraction (HS-SPME) technique and analyzed by GC-MS. A total of 200 compounds were detected and identified from organic extracts, while the water extracts contained only traces of few volatiles. The CH2Cl2 extract of the R. luteum flowers was found to exhibit the most diverse composition: 34 compounds were identified, with benzyl alcohol (16.6%), limonene (14.6%) and p-cymene (8.4%) being the major compounds. The CH2Cl2-solubles of R. x sochadzeae leaves contained only phenyl ethyl alcohol. This study indicated appreciable intra-specific variations in volatile compositions within the genus. Different anatomical parts also showed altered volatile profiles. This is the first application of HS-SPME-GC-MS on the volatiles of Rhododendron species.


Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 115 ◽  
Author(s):  
Xian-kui Ma ◽  
Xiao-fei Li ◽  
Jian-yong Zhang ◽  
Jie Lei ◽  
Wei-wei Li ◽  
...  

Selaginella doederleinii (SD) is a perennial medicinal herb widely distributed in China. In this study, the volatile components of SD from two regions (24 batches), namely Zhejiang and Guizhou, were determined by combining headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME/GC-MS). After investigating different influence factors, the optimal conditions for extraction were as follows: The sample amount of 1 g, the polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber of 65 µm, the extraction time of 20 min, and the extraction temperature of 100 °C. Based on the above optimum conditions, 58 volatiles compounds, including 20 terpenes, 11 alkanes, 3 alcohols, 6 ketones, 3 esters, 11 aldehydes, 1 ether, 1 aromatic, 1 phenol, and 1 furan, were found and identified in SD. Furthermore, hierarchical cluster analysis and principal component analysis were successfully applied to distinguish the chemical constituents of SD from two regions. Additionally, anethol, zingerone, 2,4-di-tert-butylphenol, ledene, hexyl hexanoate, α-cadinol, phytone, hinesol, decanal, octadecene, cedren, 7-tetradecene, copaene, β-humulene, 2-butyl-2-octenal, tetradecane, cedrol, calacorene, 6-dodecanone, β-caryophyllene, 4-oxoisophorone, γ-nonanolactone, 2-pentylfuran, 1,2-epoxyhexadecane, carvacrol, n-pentadecane, diisobutyl phthalate, farnesene, n-heptadecane, linalool, 1-octen-3-ol, phytane, and β-asarone were selected as the potential markers for discriminating SD from 24 habitats in Zhejiang and Guizhou by partial least squares discrimination analysis (PLS-DA). This study revealed the differences in the components of SD from different regions, which could provide a reference for the future quality evaluation.


Separations ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 75
Author(s):  
Natalia Manousi ◽  
Erwin Rosenberg ◽  
George A. Zachariadis

A novel sample preparation method based on the use of the Arrow solid-phase microextraction device was used to extract and preconcentrate volatile organic compounds (VOCs) from milk samples prior to their determination by gas chromatography–mass spectrometry (GC-MS). The experimental parameters of the solid-phase microextraction (SPME) Arrow method were evaluated in terms of fiber type, sample volume, extraction temperature, extraction time, stirring rate and salt addition. Under the optimum extraction conditions, the SPME Arrow was compared with conventional SPME fibers to evaluate the effectiveness of the SPME Arrow method. Evaluation of the conventional SPME procedure was also performed under optimized conditions, for appropriate method comparison. Due to the larger sorption phase volume of SPME Arrow, a higher sensitivity and reproducibility were observed for the determined chromatographic peaks in comparison with conventional SPME fibers. The use of Carbon wide range (WR) SPME Arrow/polydimethylsiloxane (CAR/PDMS) SPME Arrow fibers leads to a compound-dependent improvement of a factor of 4–5x over the classical SPME setup. Moreover, the relative standard deviation (RSD) of the total volatiles for a conventional SPME procedure was 12.5%, while for SPME Arrow it was 6.2%. Finally, the novel method was successfully employed for the analysis of commercially available milk samples. The findings of this study indicate that SPME Arrow can be effectively used for the determination of volatile organic compounds in complex food matrixes.


Author(s):  
Pannipa Janta ◽  
Chadin Kulsing ◽  
Thumnoon Nhujak

Gas chromatography-olfactometry/mass spectrometry coupled with headspace-solid phase microextraction (HS-SPME/GC-O/MS) was applied for the characterization of volatile compounds in Tom Yum soup and its individual ingredients. Using HS-SPME with a 50/30 µm DVB/CAR/PDMS fiber and an extraction temperature of 40 °C for 50 min along with an HP-5MS capillary column, 101 peaks in the HS-SPME/GC-MS chromatogram of Tom Yum soup were detected, and 96 compounds were identified including alcohols, aldehydes, esters, ethers, and terpenes. These findings are based on the comparison of MS spectra with the NIST library as well as experimental and literature retention index data. In comparison with the compound profiles of each individual ingredient of Tom Yum soup (both before and after cooking), five extra volatile compounds in Tom Yum soup were found after the cooking process. Furthermore, odor descriptions of the eighteen aroma compounds in Tom Yum soup, along with the odor ingredient sources, were also obtained.


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