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Chuntonov, K. A., V. G. Postovalov y A. G. Kesarev. "Evaporation of volatile component from intermetallic granule with non-volatile component shell". Vacuum 55, n.º 2 (noviembre de 1999): 101–7. http://dx.doi.org/10.1016/s0042-207x(99)00134-7.
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Yu, T., H. Yao, S. Qi y J. Wang. "GC-MS analysis of volatiles in cinnamon essential oil extracted by different methods". Grasas y Aceites 71, n.º 3 (26 de agosto de 2020): 372. http://dx.doi.org/10.3989/gya.0462191.
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Cinnamon essential oil (CEO) was extracted by three different methods: steam distillation (SD), ultrasound-assisted steam distillation (UASD) and microwave-assisted steam distillation (MASD). The volatiles in CEO were separated and identified by gas chromatography–mass spectrometry (GC-MS), and the differences in volatiles among the three different methods were further analyzed through principal component analysis. The results showed that 36 individual volatile components were present in the CEO from the three different methods. In general, the numbers of aldehydes, esters, alcohols, terpenes, aromatics and ketones were 6, 3, 7, 17, 2, and 1, respectively. The most abundant volatile component was determined to be cinnamic aldehyde. The content of total cinnamic aldehydes, which determines the price of CEO, was the highest among the three methods in the UASD sample (85.633%). Moreover, the highest yield (8.33‰) of essential oil was extracted by the UASD method. Therefore, UASD was the best way for CEO extraction in this research and was recommended for future industrial applications.
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Zhao, Yongqi, Zhenling Zhang, Hongwei Zhang, Yanbang Shi y Yiming Wang. "Gas Chromatographic-Ion Mobility Spectrometry Combined with Chemometrics to Study the Changes in Characteristic Odor Components of Galli gigerii Endothelium Corneum in Different Processing Methods". Journal of Analytical Methods in Chemistry 2023 (7 de agosto de 2023): 1–11. http://dx.doi.org/10.1155/2023/2259280.
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Galli gigerii endothelium corneum (GGEC) is a traditional Chinese medicine commonly used in clinical practice to treat various conditions such as indigestion, vomiting, spermatorrhea, and enuresis. In this study, the volatile components of different concoctions of GGEC were examined by gas chromatography-ion mobility spectrometry (GC-IMS), and the changes of the components were compared by fingerprinting, combined with principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) to analyze the main volatile components and find out the different markers that can distinguish the different concoctions of GGEC. In the result, the GC-IMS fingerprints of GGEC and its different concoctions showed differences in their volatile components, of which 49 volatiles were clearly characterized, with some components including monomers and dimers. The characteristic volatile components of raw GGEC (SP) were n-nonanal, (E)-2-octenal, beta-ocimene, 2-ethyl-1-hexanol, etc. The characteristic volatile components of stir-fried GGEC (QC) are heptanal, 2-octanol, (E)-2-heptenal, etc. The characteristic volatile components of sand ironing GGEC (ST) are isoamyl acetate, decanal, cyclohexanone, 2-ethyl pyrazine, etc. The characteristic volatile components of stir-fried GGEC with vinegar (CZ) are thiazole, linalool, 2,3,5-trimethylpyrazine, etc. The characteristic volatile components of stir-fried GGEC with milk (FH) are 2-methylbutanoic acid, ethyl acetate, ethyl 2-hydroxypropanoate, butyl acetate, etc. By chemometric analysis, components such as n-nonanal, (E)-2-octenal, 2-pentyl-furan, butanal, 1,4-dioxane, and 2-methylpropanoic acid could be used as difference markers to distinguish different concoction products of GGEC. Furthermore, by analyzing different volatile compounds, we can examine the changes in volatile components during processing of GGEC, which can provide experimental data for the identification and establishment of quality standards.
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Xiang, Nan, Yihan Zhao, Bing Zhang, Qiuming Gu, Weiling Chen y Xinbo Guo. "Volatiles Accumulation during Young Pomelo (Citrus maxima (Burm.) Merr.) Fruits Development". International Journal of Molecular Sciences 23, n.º 10 (18 de mayo de 2022): 5665. http://dx.doi.org/10.3390/ijms23105665.
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As widely planted fruits with high nutritional and medical values, pomelos are managed systematically to achieve the largest economic benefits. But the annual shedding of young pomelos, which could be applied as feedstocks for essential oil extraction with their abundant volatiles, leads to a waste of source. The present study selected two commonly planted pomelo (Citrus maxima (Burm.) Merr.) varieties in Southern China, to investigate the volatile profiles during young pomelo fruits development. Combing transcriptomic analysis, this study aimed at identifying the prominent volatile components in young pomelo fruits in order to preferably extract profitable volatiles, as well, increasing the knowledge concerning regulatory roles of transcription factors (TFs) on volatiles accumulation in young pomelos. Totally 29 volatiles were identified, including 14 monoterpenoids and 13 sesquiterpenoids. Diprene was the principal component with the highest amount. Volatiles were generally decreased during fruits development but preferable stages were figured out for volatile collections. 12 and 17 TFs were related to developing time while ERF003 and MYC2 were highly correlated to monoterpenoids. These findings put forward the comprehensive usages of young pomelos and enriched the regulatory roles of TFs on both fruit development and volatiles metabolism.
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Aschariyaphotha, Wattana, Chalermchai Wongs-Aree, Kitti Bodhipadma y Sompoch Noichinda. "Fruit Volatile Fingerprints Characterized among Four Commercial Cultivars of Thai Durian (Durio zibethinus)". Journal of Food Quality 2021 (4 de septiembre de 2021): 1–12. http://dx.doi.org/10.1155/2021/1383927.
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Ripe durian fruits produce unique volatiles of pungent odor comprising esters, alcohols, ketones, and sulfur-containing compounds. Recently, “Chanthaburi 1” hybrid bred from 2 famous commercial cultivars of “Chanee” and “Monthong” claimed to be less fragrant during ripening, but there was no report. The present study compared the volatile profiles from 3 Thai commercial cultivars of “Kanyao,” “Chanee,” and “Monthong” compared to “Chanthaburi 1”, and the relationships of the cultivars were organized using the volatile fingerprints. Out of 41 volatile compounds detected by SPME/GC-MS in ripe durian flesh, 33 compounds were esters, but only 14 esters were found in “Chanthaburi 1.” Ripe flesh of most durian cultivars contains ethyl-2-methyl butanoate and ethyl hexanoate as the active volatiles. “Chanthaburi 1” contained fewer components with low odor activity value (OAV) of the volatiles. “Chanee” ripe flesh exhibited the strongest durian smell among the four varieties, whereas “Monthong” exhibited a strong apple-like fruity odor and “Kanyao” was more green fruity. Diethyl disulfide and 3, 5 dimethyl-1, 2, 4-trithiolane contributing pungent smells of garlic or onion were found only in “Chanthaburi 1” and “Monthong.” In terms of detected volatiles, “Kanyao” and “Chanee” were highly close when “Monthong” was apart. PCA analysis revealed that “Chanthaburi 1” contained ester compounds ancestrally related to the parents, “Chanee” in the component I and “Monthong” in the component II. These data could be beneficial for managing the status of Thai durians in global markets.
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Zatolokina, K. I., A. A. Tomilenko, T. A. Bul’bak y G. G. Lepezin. "Volatile Components in Cordierite and Coexisting Tourmaline and Quartz from Pegmatites of the Kuhilal Deposit (Pamir, Tajikistan)". Russian Geology and Geophysics 62, n.º 10 (1 de octubre de 2021): 1157–74. http://dx.doi.org/10.2113/rgg20204224.
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Abstract —The compositions of volatile components in cordierite, tourmaline, and quartz from pegmatites of the Kuhilal deposit were studied by pyrolysis-free gas chromatography–mass spectrometry (GC–MS), IR and Raman spectroscopy, and microthermometry, and their comparative analysis was performed. Capillary GC–MS was applied to determine the component composition and relative contents (rel.%) of volatiles from different zones of crystals and fractions of cordierite. It has been established that water and carbon dioxide prevail among them. Among hydrocarbons, aliphatic, cyclic, and oxygenated ones are predominant. Heterocyclic, nitrogenated, and sulfonated compounds have also been found. In tourmaline and quartz, volatile components are present in gas–liquid inclusions; in cordierites, they are localized both in structural cavities and in nonstructural positions.
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Xi, Jiapei, Ping Zhan, Honglei Tian y Peng Wang. "Effect of Spices on the Formation of VOCs in Roasted Mutton Based on GC-MS and Principal Component Analysis". Journal of Food Quality 2019 (10 de septiembre de 2019): 1–11. http://dx.doi.org/10.1155/2019/8568920.
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Peppertree prickly ash, Amomum tsao-ko, cumin, and ginger have long been used in Asian countries to modify the flavor and to partially neutralize any unpleasant odors present in roast lamb. The purpose of this study was to evaluate the change in the amount of volatile components present in roast lamb compared to meat added with peppertree prickly ash, Amomum tsao-ko, cumin, and ginger. Principal component analysis was carried out on the 27 initially selected from 88 volatile substances, and 15 substances with a projection of more than 0.25 in the load matrix were used as indicators to study the different contents in roasted mutton and lamb prepared by adding peppertree prickly ash, Amomum tsao-ko, cumin, and ginger. The types of VOCs (volatile organic compounds) detected in roast meat without adding spices were the least. Roast meat with the addition of cumin leads to the strongest content of aldehydes, followed by the addition of Amomum tsao-ko. Additionally, roast meat with the addition of Chinese prickly ash leads to the strongest content of terpenes, followed by the addition of ginger. Moreover, with the addition of spices, the content of volatiles responsible for the presence of a mutton odor (such as hexanal, heptanal, pentanal, (z)-4-decenal, benzaldehyde, p-propyl-anisole, and dimethyl ether) was not significantly decreased, and in fact some volatiles increased in amount such as pentanal, hexanal, octanal, and (z)-4-decenal. In conclusion, the effect of addition of spices on the volatile profile of roasted mutton and lamb can be attributed to the generation of flavor volatiles mainly derived from raw spices’ hot action, with few additional volatiles formed during boiling.
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Bruce, Toby J. A., Charles A. O. Midega, Michael A. Birkett, John A. Pickett y Zeyaur R. Khan. "Is quality more important than quantity? Insect behavioural responses to changes in a volatile blend after stemborer oviposition on an African grass". Biology Letters 6, n.º 3 (23 de diciembre de 2009): 314–17. http://dx.doi.org/10.1098/rsbl.2009.0953.
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Plants subjected to insect attack usually increase volatile emission which attracts natural enemies and repels further herbivore colonization. Less is known about the capacity of herbivores to suppress volatiles and the multitrophic consequences thereof. In our study, the African forage grass, Brachiaria brizantha , was exposed to ovipositing spotted stemborer, Chilo partellus , moths. A marked reduction in emission of the main volatile, ( Z )-3-hexenyl acetate ( Z 3HA), occurred following oviposition but the ratio of certain other minor component volatiles to Z 3HA was increased. While further herbivore colonization was reduced on plants after oviposition, the new volatile profile caused increased attraction of an adapted parasitoid, Cotesia sesamiae . Our results show that insect responses are dependent on the quality of volatile emission rather than merely the quantity in this multitrophic interaction.
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Zhang, Wei y Xianrui Liang. "Headspace Gas Chromatography-Mass Spectrometry for Volatile Components Analysis in Ipomoea Cairica (L.) Sweet Leaves: Natural Deep Eutectic Solvents as Green Extraction and Dilution Matrix". Foods 8, n.º 6 (11 de junio de 2019): 205. http://dx.doi.org/10.3390/foods8060205.
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In this study, natural deep eutectic solvents (NADESs) were used as both the extraction and dilution matrix in static headspace gas chromatography-mass spectrometry (SHS-GC-MS) for the analysis of volatile components in Ipomoea cairica (L). Sweet (ICS) leaves. Six NADESs were prepared and the NADESs composed of choline chloride and glucose with a 1:1 molar ratio containing 15% water were preferred due to the better peak responses. A total of 77 volatiles in ICS leaves were detected and tentatively identified by mass spectral matching with the US National Institute of Standards and Technology (NIST, 2014) Mass Spectral Library and the retention index-assisted qualitative method. These 77 volatile components were mainly terpenoids, aromatics, and aliphatics. Among them, β-elemene, β-caryophyllene, α-humulene, and 2, 4-di-tert-butylphenol were found to be the main components. This investigation verified that the use of NADESs is an efficient green extraction and dilution matrix of the SHS-GC-MS method for direct volatile component analysis of plant materials without extra extraction work.
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Kostic, Emilija, Dusanka Kitic, Maja Vujovic, Marija Markovic, Aleksandra Pavlovic y Gordana Stojanovic. "A chemometric approach to the headspace sampled volatiles of selected Salvia species from Southeastern Serbia". Botanica Serbica 46, n.º 2 (2022): 285–94. http://dx.doi.org/10.2298/botserb2202285k.
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Headspace sampling is a fast, simple and economical way to prepare plant samples for analysis by gas chromatography. For the first time, the composition of the head space volatiles (HSV) of six Salvia species (S. verticillata, S. glutinosa, S. nemorosa, S. aethiopis, S. amplexicaulis and S. officinalis) in the flowering stage and two (S. glutinosa and S. sclarea) in the fruiting stage from Southeastern Serbia was analysed using the GC-FID-MS technique after headspace sampling. The chemical composition of the highly volatile compounds of the analysed species varies considerably. Monoterpene hydrocarbons represented the dominant class of volatile compounds in all the Salvia species, except for S. sclarea and S. aethiopis. The content of sesquiterpenes was the highest in S. aethiopis (96.9%) and S. glutinosa in the flowering phase (29.5%), while in all the other samples that percentage was below 10%. Oxygenated monoterpenes were the most abundant in S. sclarea, where the main component was oxygenated monoterpene linalyl acetate (97.7%). The main component of S. verticillata was ?-phellandrene, and its content varied depending on the plant location and sampling time. The main component of S. glutinosa in the flowering phase was limonene (16.6%), and in the fruiting phase sabinene (87.1%). Headspace analysis of the volatile components of S. aethiopis was carried out for the first time and the most abundant detected components were sesquiterpenes: (E)- caryophyllene (36.8%), ?-copaene (33.4%) and ?-elemene (7.3%). The analysis of the principal components was performed to interpret the grouping patterns, as well as to analyse the similarities and differences between the samples in terms of the composition of the volatile components. The samples were grouped into three clusters. The first cluster consisted of samples of S. verticillata (S1, S4 and S5) from different locations, the second comprised samples of S. glutinosa (S3), S. aethiopis (S8), S. amplexicaulis (S9) and S. officinalis (S10), while samples of S. nemorosa (S7) made up the third cluster. The HS-GC-FID-MS technique can be successfully used for the qualitative and quantitative analysis of volatile compounds of different Salvia species. The obtained results are important for evaluating the possibility of using different types of sage.
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Sakurai, Kazutoshi, Kenichi Tomiyama, Yukihiko Kawakami, Nozomi Ochiai, Shigeki Yabe, Tomomi Nakagawa y Yoshinori Asakawa. "Volatile Components Emitted from the Liverwort Marchantia Paleacea Subsp. Diptera". Natural Product Communications 11, n.º 2 (febrero de 2016): 1934578X1601100. http://dx.doi.org/10.1177/1934578x1601100232.
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The volatile components from the thalloid liverwort, Marchantia paleacea subsp. diptera were investigated by HS-SPME-GC-MS analysis. The monocyclic monoterpene aldehyde, perillaldehyde was identified for the first time as the major component and its content was about 50% of the volatiles, along with β-pinene, limonene, β-caryophyllene, α-selinene and β-selinene as minor volatiles. Using MD (Multi-dimensional) GC-MS analysis equipped with a chiral column as the second column, the chirality was determined of both perillaldehyde and limonene, which was considered as the precursor of perillaldehyde,. Both compounds were ( S)-(-)-enantiomers (over 99.0 %) and ( R)-enantiomers (less than 0.5 %). This is the first report of the existence of perillaldehyde in liverworts.
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Hernowo, Pandit, Carolus B. Rasrendra, Yogi W. Budhi, Jenny Rizkiana, Anton Irawan, Septhian Marno, Yana Meliana, Oki Muraza y Yazid Bindar. "Volatile State Mathematical Models for Predicting Components in Biomass Pyrolysis Products". Journal of Engineering and Technological Sciences 54, n.º 1 (2 de febrero de 2022): 220108. http://dx.doi.org/10.5614/j.eng.technol.sci.2022.54.1.8.
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Volatile state mathematical models for quantifying the chemical components in volatile biomass pyrolysis products were developed. The component mass yield Yi rate depends linearly on its pseudo kinetic constant and the remaining mass yield. The mass fraction rate of each component was modeled from the derivation of its mass yield rate equation. A new mathematical model equation was successfully developed. The involved variables are: biomass number, temperature, heating rate, pre-exponential factor, and pseudo activation energy related to each component. The component mass fraction yi and the mass yield were predicted using this model within a temperature range. Available experimental pyrolysis data for beechwood and rice husk biomass were used to confirm the developed model. The volatile products were separated into bio-pyrolysis gas (BPG) and a bio-pyrolysis oil (BPO). Five components in the BPG and forty in the BPO were quantified. The pseudo activation energy for each pseudo chemical reaction for a specific component was modeled as a polynomial function of temperature. The component mass fraction and yield are quantifiable using this developed mathematical model equation within a temperature range. The predicted component mass fractions and yields agreed excellently with the available experimental data.
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Osman, Che Puteh, Noraini Kasim, Nur Syamimi Amirah Mohamed Salim y Nuralina Abdul Aziz. "Discrimination of 11 Malaysian Durian Cultivars Based on Sulfur-Containing Volatiles and Esters Using Multivariate Data Analysis". Natural Product Communications 17, n.º 1 (enero de 2022): 1934578X2110692. http://dx.doi.org/10.1177/1934578x211069235.
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There are reports documenting the volatile oils of several durian cultivars in Malaysia. However, there is limited information on the rapid discrimination of the durian cultivars based on the composition of the total volatiles and individual volatile compounds. Thus, the present work aims to discriminate 11 Malaysian durian cultivars based on their volatile compositions using multivariate data analysis. Sulfur-containing volatiles are the major volatiles in D175 (Udang Merah), D88 (Darling), D13 (Golden Bun), DXO (D24 Special), D17 (Green Bamboo), D2 (Dato Nina), and D168 (Hajah Hasmah) durian cultivars, while esters are predominant in D99 (Kop Kecil), D24 (Bukit Merah), and D160 (Musang Queen) durian cultivars. D197 (Musang King) cultivar has an almost equal composition of sulfur-containing volatiles and esters. In the ester predominated volatile durian oil, ethyl 2-methylbutanoate and propyl 2-methylbutanoate are the major volatile compounds, while the durian cultivars with predominant sulfur-containing volatiles mainly contain diethyl disulfide, diethyl trisulfide, and 3,5-dimethyl-1,2,4-trithiolane. The durian cultivars were clustered into 8 clusters using principal component analysis, with 3 clusters consisting of 2 cultivars, and with the remaining cultivars clustered individually. The highly sought-after durian cultivars, D160 and D197, were clustered into one. Hierarchal clustering analysis identified the distinct compounds which discriminate every durian cultivar.
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Wang, Kai, Bowen Ma, Tao Feng, Da Chen, Linyun Yao, Jun Lu y Min Sun. "Quantitative analysis of volatile compounds of four Chinese traditional liquors by SPME-GC-MS and determination of total phenolic contents and antioxidant activities". Open Chemistry 19, n.º 1 (1 de enero de 2021): 518–29. http://dx.doi.org/10.1515/chem-2021-0039.
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Abstract The aim of this work was to investigate the volatile compositions of four Chinese functional liquors. For this purpose, volatile compounds of four liquors were extracted with head-space solid-phase microextraction (HS-SPME) and analyzed with gas chromatography-mass spectrometry (GC-MS) along with the determination of odor activity value (OAV) and relative odor contribution (ROC). Sixty volatiles were tentatively identified and categorized into the following seven groups: alcohols, esters, fatty acids, carbonyl compound, hydrocarbons, phenols, and other components. The differences in chemical composition of volatile compounds were visualized with heat maps. Odorants were compared with different samples using a statistical analysis of Venn diagrams and a multivariate principal component analysis, and ethyl hexanoate, ethyl acetate, and ethyl octanoate were found to be the key odorants. Besides, abundant phenolic contents and high antioxidant ability of four Chinese functional liquors could potentially bring better health-boosting effects.
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Zhang, Li, Si Mi, Ruobing Liu, Yaxin Sang y Xianghong Wang. "Evaluation of Volatile Compounds in Milks Fermented Using Traditional Starter Cultures and Probiotics Based on Odor Activity Value and Chemometric Techniques". Molecules 25, n.º 5 (3 de marzo de 2020): 1129. http://dx.doi.org/10.3390/molecules25051129.
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The volatile components of milks fermented using traditional starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricus) and probiotics (Lactobacillus lactis, Lactobacillus bifidus, Lactobacillus casei, and Lactobacillus plantarum) were investigated by means of gas chromatography-mass spectrometry (GC-MS) combined with simultaneous distillation extraction (SDE). A total of 53 volatile compounds were detected, being 10 aldehydes, 11 ketones, 10 acids, 11 hydrocarbons, 7 benzene derivatives, and 4 other compounds. The starter culture was found to significantly affect the composition of volatile components in the fermented milks. Ketones and hydrocarbons were the dominant compounds in milk before fermentation, while acids were dominant compounds in the fermented samples. Compared with probiotics, there was greater abundance of volatile components in fermented milks with traditional strains. The importance of each volatile compound was assessed on the basis of odor, thresholds, and odor activity values (OAVs). Of the volatile compounds, 31 of them were found to be odor-active compounds (OAV > 1). The component with the highest OAVs in most samples was (E,E)-2,4-decadienal. Heatmap analysis and principal component analysis were employed to characterize the volatile profiles of milks fermented by different starter cultures. The results could help to better understand the influence of starter cultures on the odor quality of milks.
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Mahan, Brandon, Frédéric Moynier, Julien Siebert, Bleuenn Gueguen, Arnaud Agranier, Emily A. Pringle, Jean Bollard, James N. Connelly y Martin Bizzarro. "Volatile element evolution of chondrules through time". Proceedings of the National Academy of Sciences 115, n.º 34 (6 de agosto de 2018): 8547–52. http://dx.doi.org/10.1073/pnas.1807263115.
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Chondrites and their main components, chondrules, are our guides into the evolution of the Solar System. Investigating the history of chondrules, including their volatile element history and the prevailing conditions of their formation, has implications not only for the understanding of chondrule formation and evolution but for that of larger bodies such as the terrestrial planets. Here we have determined the bulk chemical composition—rare earth, refractory, main group, and volatile element contents—of a suite of chondrules previously dated using the Pb−Pb system. The volatile element contents of chondrules increase with time from ∼1 My after Solar System formation, likely the result of mixing with a volatile-enriched component during chondrule recycling. Variations in the Mn/Na ratios signify changes in redox conditions over time, suggestive of decoupled oxygen and volatile element fugacities, and indicating a decrease in oxygen fugacity and a relative increase in the fugacities of in-fluxing volatiles with time. Within the context of terrestrial planet formation via pebble accretion, these observations corroborate the early formation of Mars under relatively oxidizing conditions and the protracted growth of Earth under more reducing conditions, and further suggest that water and volatile elements in the inner Solar System may not have arrived pairwise.
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Yang, Lvzhu, Jie Liu, Xinyu Wang, Rongrong Wang, Fang Ren, Qun Zhang, Yang Shan y Shenghua Ding. "Characterization of Volatile Component Changes in Jujube Fruits during Cold Storage by Using Headspace-Gas Chromatography-Ion Mobility Spectrometry". Molecules 24, n.º 21 (30 de octubre de 2019): 3904. http://dx.doi.org/10.3390/molecules24213904.
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Volatile components in jujube fruits from Zizyphus jujuba Mill. cv. Dongzao (DZ) and Zizyphus jujuba Mill. cv. Jinsixiaozao (JS) were analyzed under different cold storage periods via headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). Results identified 53 peaks that corresponded to 47 compounds and were mostly alcohols, aldehydes, esters, and ketones. Differences in the volatile components of jujube fruits were revealed in topographic plots and fingerprints. For DZ, 3-pentanone was the characteristic component of fresh fruits. After storage for 15 days, dipropyl disulfide became the most special substance. Moreover, when stored for 30 and 45 days, the fruits had some same volatile components, like 2-pentyl furan and diallyl sulfide. However, for DZ stored for 60 days, esters were the prominent constituent of the volatile components, simultaneously, some new alcohols appeared. For JS, 2-ethyl furan was the representative of fresh fruits, and 2-butoxyethanol content was the most abundant after 15 and 30 days of storage. Different from that in DZ, the content of ester in JS increased after storage for 45 days. Substances such as amyl acetate dimer, methyl salicylate, and linalool greatly contributed to the jujube flavor during the late storage period. Principal component analysis (PCA) showed that fresh samples and refrigerated fruits were effectively distinguished. Heat map clustering analysis displayed the similarity of volatile components in different samples and was in accordance with PCA results. Hence, the volatile components of jujube fruits can be readily identified via HS-GC-IMS, and jujube fruits can be classified at different periods based on the difference of volatile components.
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Zhou, Qi, Man Shi, Huihui Zhang y Zunling Zhu. "Comparative Study of the Petal Structure and Fragrance Components of the Nymphaea hybrid, a Precious Water Lily". Molecules 27, n.º 2 (9 de enero de 2022): 408. http://dx.doi.org/10.3390/molecules27020408.
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Nymphaea hybrid, a precious water lily, is a widely-cultivated aquatic flower with high ornamental, economic, medicinal, and ecological value; it blooms recurrently and emits a strong fragrance. In the present study, in order to understand the volatile components of N. hybrid and its relationship with petals structure characteristics, the morphologies and anatomical structures of the flower petals of N. hybrid were investigated, and volatile compounds emitted from the petals were identified. Scanning and transmission electron microscopy were used to describe petal structures, and the volatile constituents were collected using headspace solid-phase microextraction (HS-SPME) fibers and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). The results indicated that the density and degree of protrusion and the number of plastids and osmiophilic matrix granules in the petals play key roles in emitting the fragrance. There were distinct differences in the components and relative contents of volatile compounds among the different strains of N. hybrid. In total, 29, 34, 39, and 43 volatile compounds were detected in the cut flower petals of the blue-purple type (Nh-1), pink type (Nh-2), yellow type (Nh-3) and white type (Nh-4) of N. hybrid at the flowering stage, with total relative contents of 96.78%, 97.64%, 98.56%, and 96.15%, respectively. Analyses of these volatile components indicated that alkenes, alcohols, and alkanes were the three major types of volatile components in the flower petals of N. hybrid. The predominant volatile compounds were benzyl alcohol, pentadecane, trans-α-bergamotene, (E)-β-farnesene, and (6E,9E)-6,9-heptadecadiene, and some of these volatile compounds were terpenes, which varied among the different strains. Moreover, on the basis of hierarchical cluster analysis (HCA) and principal component analysis (PCA), the N. hybrid samples were divided into four groups: alcohols were the most important volatile compounds for Nh-4 samples; esters and aldehydes were the predominant volatiles in Nh-3 samples; and ketones and alkenes were important for Nh-2 samples. These compounds contribute to the unique flavors and aromas of the four strains of N. hybrid.
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Huopalahti, Rainer, Eila Kesälahti y Reino Linko. "Effect of hot air and freeze drying on the volatile compounds of dill (Anethum graveolens L.) herb". Agricultural and Food Science 57, n.º 2 (1 de mayo de 1985): 133–38. http://dx.doi.org/10.23986/afsci.72194.
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Volatile compounds of fresh, hot air dried and freeze dried dill (Anethum graveolens L.) herb were studied by gas chromatography-mass spectrometry. Of the 25 volatile components identified, 16 the most abundant compounds were analysed quantitatively. The major primary aroma compounds were α-phellandrene, 3,6-dimethyl-2,3,3a,4,5,7a-hexahydrobenzofuran,β-phellandrene, limonene, α-pinene, p-cymene and myristicin. Severe loss of these components occured during the drying of dill. E.g. the retention of the benzofuranoid, the most important aroma component of the dill herb, was from trace to 1.3 % in hot air dried samples and 3.5—20 % in freeze dried samples. During the drying secondary aroma compounds are formed consisting over 50 % of the total volatiles. Among these phytadienes, especially neophytadiene, were the major components. The best result was obtained by freeze drying, but the product contained only one quarter of the total aroma compounds of the fresh dill herb.
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Yang, Long Hui, Ping Xian, Hong Bin Yang, Xiao Ping Li, Ming Tang y Xi Liu. "Characteristics Analysis of Blending Combustion Component of the Guangxi Urban Sludge". Applied Mechanics and Materials 295-298 (febrero de 2013): 1669–74. http://dx.doi.org/10.4028/www.scientific.net/amm.295-298.1669.
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The research was the character of the urban sludge burning with coal by using the elemental anaylsis, component analysis, proximate analysis and thermogravimetric analysis. There is a big different elemental composition between the urban sludge and coal. For example, the carbon content (20.64%) in the sludge is only 31.3% of the coal. SiO2 in sludge incineration ash contain up to 15%, the same as SiO2 in Siliceous clinker. The sludge ash content (56.46%) is 2 times of in coal ash, anSubscript textd the volatile of sludge (34.6377%)is higher than the volatile of coal (25.089%), the sludge incineration can be divided into three stages: moisture volatilizing stage (30°C to 160°C), devolatilization combustion stage (160°C to 500°C) and fixed carbon and residual combustibles burning stage (510°C to 950°C). The heating rate increased, the volatiles volatilized advance about 50°C. Therefore, the sludge is a high value fuel, which can be used in the burning with coal or building materials.
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YALÇINKAYA, Zeki y Hasan CEYLAN. "Adsorption and Desorption of Major Gases on Some Clays Obtained by Heating Tobacco at Certain Temperatures". MAS Journal Of Applied Sciences 7, n.º 11 (10 de marzo de 2022): 262–76. http://dx.doi.org/10.52520/masjaps.230.
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The tobacco roasting-process was carried out and a study was carried out on the composition of the gases released during this process. It has been determined that the amounts of substances obtained from the studied tobacco are generally less than the amounts of substances obtained in the literature. The volatile gases formed during this roasting were passed over some clay minerals and adsorbed on them. The adsorbed components were desorbed by diethyl ether extraction. Adsorption and desorption analyzes were investigated by GC and TG techniques. The components released during the tobacco-roasting process were first directly obtained and analyzed by gas chromatography. Then, the adsorbing efficiency to clay for each of the components in the vapors from tobacco was calculated by comparing the amount of the component retained in the absence of adsorbent with the amount retained after the component was passed over the adsorbent. The structure of the clay samples used as adsorbent was investigated by chemical analysis and DTA techniques. The adsorption efficiencies are discussed with the physical properties of the clays, the affinities of the volatile components, and their adsorption efficiency. Most of the volatiles adsorbed on the adsorbents were recovered by diethyl ether extraction. Especially benzaldehyde, propionic acid, furfuryl alcohol, 3-methylbutanoic acid and nicotine were recovered with good yield.
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He, Ye, Lu Yin, Wei Zhou, Hongyan Wan, Chang Lei, Shunxiang Li y Dan Huang. "Evaluation of 60Co Irradiation on Volatile Components of Turmeric (Curcumae Longae Rhizoma) Volatile Oil with GC–IMS". Foods 12, n.º 13 (26 de junio de 2023): 2489. http://dx.doi.org/10.3390/foods12132489.
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60Co irradiation is an efficient and rapid sterilization method. The aim of this work is to determine the changes in essential-oil composition under different irradiation intensities of 60Co and to select an appropriate irradiation dose with GC–IMS. Dosages of 0, 5, and 10 kGy of 60Co were used to analyze turmeric (Curcumae Longae Rhizoma) volatile oil after 60Co irradiation (named JH-1, JH-2, and JH-3). The odor fingerprints of volatile organic compounds in different turmeric volatile oil samples were constructed by headspace solid-phase microextraction and gas chromatography–ion mobility spectrometry (GC–IMS) after irradiation. The differences in odor fingerprints of volatile organic compounds (VOCs) were compared by principal component analysis (PCA). The results showed that 97 volatile components were detected in the volatile oil of Curcuma longa, and 64 components were identified by database retrieval. With the change in irradiation intensity, the volatile compounds in the three turmeric volatile oil samples were similar, but the peak intensity was significantly different, which was attributed to the change in compound composition and content caused by different irradiation doses. In addition, the principal component analysis showed that JH-2 and JH-3 were relatively correlated, while JH-1 and JH-3 were far from each other. In general, different doses of 60Co irradiation can affect the content of volatile substances in turmeric volatile oil. With the increase in irradiation dose, the peak area decreased, and so the irradiation dose of 5 kGy/min was better. It is shown that irradiation technology has good application prospects in the sterilization of foods with volatile components. However, we must pay attention to the changes in radiation dose and chemical composition.
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Pestoni, B., K. Altwegg, H. Balsiger, N. Hänni, M. Rubin, I. Schroeder, M. Schuhmann y S. Wampfler. "Detection of volatiles undergoing sublimation from 67P/Churyumov-Gerasimenko coma particles using ROSINA/COPS". Astronomy & Astrophysics 645 (enero de 2021): A38. http://dx.doi.org/10.1051/0004-6361/202039130.
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Context. The ESA Rosetta mission has allowed for an extensive in situ study of the comet 67P/Churyumov-Gerasimenko. In measurements performed by the ram gauge of the COmet Pressure Sensor (COPS), observed features are seen to deviate from the nominal ram gauge signal. This effect is attributable to the sublimation of the volatile fraction of cometary icy particles containing volatiles and refractories. Aims. The objective of this work is to investigate the volatile content of icy particles that enter the COPS ram gauge. Methods. We inspected the ram gauge measurements to search for features associated with the sublimation of the volatile component of cometary particles impacting the instrument. All the sublimation features with a high-enough signal-to-noise ratio were modelled by fitting one or more exponential decay functions. The parameters of these fits were used to categorise different compositions of the sublimating component. Results. Based on features that are attributable to ice sublimation, we infer the detection of 73 icy particles containing volatiles. Of these, 25 detections have enough volatile content for an in-depth study. From the values of the exponential decay constants, we classified the 25 inferred icy particles into three types, interpreted as different volatile compositions, which are possibly further complicated by their differing morphologies. The available data do not give any indication as to which molecules compose the different types. Nevertheless, we can estimate the total volume of volatiles, which is expressed as the diameter of an equivalent sphere of water (density of 1 g cm−3). This result was found to be on the order of hundreds of nanometres.
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Thames, S. F. y K. G. Panjnani. "Organosilanes in low volatile organic component coatings". Progress in Organic Coatings 26, n.º 1 (agosto de 1995): 63–71. http://dx.doi.org/10.1016/0300-9440(95)00590-0.
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Pu, Zhi Jun, Yu Hong Liu, Xu Kai, Fei Fei Wang, Ting Ting Song y Cheng Yi Zhang. "Ultrasonic Extraction and Component Analysis of Volatile Oil from Prunus Tomentosa Thunb Core". Applied Mechanics and Materials 675-677 (octubre de 2014): 1650–53. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.1650.
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AIIM To explore the optimal ultrasonic extraction process of volatile oil from prunus tomentosa and analyze the component. METHODS The orthogonal test was carried out with volatile oil rate t as the index,the grinding degree of material, solvent, ratio of material to liquid, ultrasonic time as factors by ultrasonic extraction method,the components were analyzed by GC-MS. RESULTS The main factors that affect the extraction of volatile oil from Prunus tomentosa thunb is extraction, followed by ultrasonic time and.grinding degree. A3B2C1D3 was the best extraction condition: Selection of ethyl ether as extraction agent, the particle size is 30 mesh, the 1:10 ratio of material to liquid, ultrasonic time for 40 min. GC-MS techniques were applied to analyze the chemical constituents of volatile oil, six kinds of main components were isolated and identified ,accumulating for 92.82% of the total volatile oil content . CONCLUSION The Ultrasonic extraction time is short, easy operation, high yield, experiment verified that the extraction rate is 0.6270% under the optimum extraction conditions and identified six main components.
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Chen, Jing y Neng Zhu. "Identification of Non-Volatile Components and Volatile Organic Compounds in Wet Building Materials". Applied Mechanics and Materials 253-255 (diciembre de 2012): 825–28. http://dx.doi.org/10.4028/www.scientific.net/amm.253-255.825.
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The major volatile components in two solvent-based paints, two thinners, and four adhesives have been identified by a method involving pre-treatment by solvent dilution, filtration, and gas chromatography-mass spectrometry. The non-volatile components in these wet building materials have been determined by infrared spectroscopy. The results have shown the major volatile organic compounds in one-component polyurethane varnish and alkyd paint thinner to be nonane, decane, undecane, xylene, ethylbenzene and ethyltoluene. The main film-forming matter in cement floor paint has been identified as styrenated acrylic emulsion, with the volatile components being mainly butyl acetate, decane and benzene series. The basic substances in these adhesives were polychloroprene, styrene butadiene carboxylated latex, or polyvinyl acetate emulsion. The primary volatile compounds in two adhesives were methyl acetate, and many branched-chain and normal alkanes, while those in the other two adhesives were toluene and benzene.
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Gregson, F. K. A., M. Ordoubadi, R. E. H. Miles, A. E. Haddrell, D. Barona, D. Lewis, T. Church, R. Vehring y J. P. Reid. "Studies of competing evaporation rates of multiple volatile components from a single binary-component aerosol droplet". Physical Chemistry Chemical Physics 21, n.º 19 (2019): 9709–19. http://dx.doi.org/10.1039/c9cp01158g.
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Buleandra, Mihaela, Zenovia Moldovan, Irinel Adriana Badea, Iulia Gabriela David, Dana Elena Popa, Eliza Oprea, Tugce Ayca Tekiner Caglar y Selma Huveyda Basaga. "Comparative Assessment of the Volatile Profile, Antioxidant Capacity and Cytotoxic Potential of Different Preparation of Millefolli Herba Samples". Revista de Chimie 71, n.º 3 (1 de enero de 2001): 69–78. http://dx.doi.org/10.37358/rc.20.3.7975.
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Millefolii herba is an available product on the Romanian market as mixture of stems, leaves and flowers of Achillea millefolium L. There were established its volatile compounds profile, total polyphenolic content (TPC), antioxidant capacity and effects on HCT 116 cell viability and programmed cell death. The infusion, hydroalcoholic extract and hydrodistillated essential oil were studied. A comparative analysis using static headspace (HS) and hydro-distillation (HD) GC/MS of the volatile components from Millefolii herba was realized: the essential oil contains chamazulene as the principal component (37.1%), while 1,8-cineole (46.8%) is the main constituent of headspace volatiles. The highest antioxidant capacity was found in essential oil, compared with hydroalcoholic extract, infusion and ascorbic acid. Yarrow hydroalcoholic extract reduced the HCT 116 cell viability and induced the apoptotic cell death in a dose and time dependent manner.
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Ren, Qin, Ling-Zhen Cao, Jian-wei Su, Ming-hui Xie, Qing-wen Zhang y Xiao-xia Liu. "Volatile Emissions from the Invasive Weed Eupatorium adenophorum Induced by Aphis gossypii Feeding and Methyl Jasmonate Treatment". Weed Science 58, n.º 3 (septiembre de 2010): 252–57. http://dx.doi.org/10.1614/ws-d-09-00002.1.
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The volatile compounds of crofton weed infested by cotton aphids and sprayed with MeJA were collected and analyzed by the TCT-GC/MS technique. The healthy weeds were controls. Seventeen volatiles identified from crofton weed included green leaf odors, monoterpenes and sequiterpenes, and oxo-compounds. Camphene, 2-carene, α-phellandrene, ρ-cymene, and caryophyllene were the major volatiles and constituted about 77% of the total volatile emissions from the control. In the aphid-infested weeds, no new induced component was found. Among the terpenes, ρ-cymene increased markedly in the infested weeds compared with the control, whereas all sesquiterpenes decreased markedly. Levels of endogenous JA in leaves and young stems of the aphid-infested weeds were markedly higher than in the control, whereas both endogenous SA level and ABA level were not significantly different. MeJA sprayed on crofton weed with the aphid infestation had a similar effect on volatile emissions. It is suggested that JA was one of the most important signals in crofton weed and could regulate the emission of volatile compounds.
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Zelinkova, Zuzana y Thomas Wenzl. "Identification of Cigarette Brands by Soft Independent Modeling of Class Analogy of Volatile Substances". Nicotine & Tobacco Research 22, n.º 6 (6 de mayo de 2019): 997–1003. http://dx.doi.org/10.1093/ntr/ntz066.
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Abstract Introduction This study aimed to develop a method for discriminating cigarette brands based on the profiles of volatile components extracted from the tobacco fraction of the finished cigarettes to authenticate branded cigarettes of unknown origin. Methods An analytical method comprising direct thermal desorption coupled with gas chromatography-quadrupole time-of-flight mass spectrometry was developed for acquiring volatile profiles of cigarettes. About 290 samples of commercially available cigarettes were analyzed. Within this batch, 123 samples represented four popular cigarette brands. They were selected for in-depth characterization. Multivariate analysis was used to investigate the interrelations among volatile compounds of cigarettes and to identify characteristic markers for the cigarette discrimination. Supervised pattern recognition techniques were used for designing classification models. Results Principal component analysis covering all detected volatiles allowed the differentiation of cigarettes based on the brand. A number of 56 volatile components were identified as markers with high discrimination power. These compounds were used for establishing classification models. A method of soft independent modeling of class analogy developed for the four studied cigarette brands proved to be efficient in the classification of unknown cigarettes, with accuracy between 95.9% and 100%. Conclusions The data evaluation by soft independent modeling of class analogy was highly accurate in classification of unknown cigarettes with a low rate of false positives and false negatives. The developed models can be used for discrimination of genuine from non-genuine products with high level of probability. Implications Profiling of volatiles, which is commonly used for authentication of different food commodities, was applied for the characterization of cigarette tobacco for the purpose of authentication a cigarette brand. Volatile components with a high discrimination power were identified by means of multivariate statistical methods and used for establishing of a classification model. The classification model was able to discriminate genuine from non-genuine cigarettes with a high level of prediction accuracy. This model could be a powerful tool for tobacco control to judge the authenticity of cigarettes.
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Özel, Abdulhabip, İslim Koşar, Tuncay Demirbilek y Kaan Erden. "Changes in yields and volatile oil composition of fennel (Foeniculum vulgare Mill.) in high plant populations". Italian Journal of Agronomy 14, n.º 3 (22 de julio de 2019): 147–52. http://dx.doi.org/10.4081/ija.2019.1347.
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This research was managed to identify the effects of the different seed quantity (5, 10, 15 and 20 kg.ha–1) and row interval (15 and 30 cm) on the yields and the volatile oil components of fennel (Foeniculum vulgare Mill.) under the Harran Plain conditions, during 2013 and 2014 years. The study was established according to the split plot in randomised complete block design. Seed and volatile oil yields, volatile oil ratio and volatile oil components were importantly affected seed quantity and row interval. The transaction of 15 cm × 10 kg.ha–1, the highest seed and volatile oil yield were taken, was determined to be the most suitable. The trans-anethole was taken the primary component under all transactions and it was changed to depend on the row interval and seed quantities.
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Wieczorek, Martyna y Henryk Jeleń. "Volatile Compounds of Selected Raw and Cooked Brassica Vegetables". Molecules 24, n.º 3 (22 de enero de 2019): 391. http://dx.doi.org/10.3390/molecules24030391.
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Brassica vegetables are a significant component of the human diet and their popularity is systematically increasing. The interest in plants from this group is growing because of numerous reports focused on their pro-health properties. However, some consumers are not enthusiastic about these vegetables because of their specific bitter taste and sharp, sulfurous aroma. In this study, the volatile composition of 15 Brassica cultivars (five Brussels sprouts, four kohlrabi, three cauliflower and three broccoli), both raw and cooked, was analyzed by solid phase microextraction and comprehensive two-dimensional gas chromatography with time of flight mass spectrometry (SPME-GC×GC-ToFMS). Differences were found between the analyzed vegetables, as well as different cultivars of the same vegetable. Moreover, the influence of cooking on the composition of volatile compounds was evaluated. All the vegetables were frozen before analyses, which is why the impact of this process on the volatile organic compounds (VOCs) was included. The most abundant groups of compounds were sulfur components (including bioactive isothiocyanates), nitriles, aldehydes and alcohols. Cooking in general caused a decrease in the abundance of main volatiles. However, the amount of bioactive isothiocyanates increased in most cultivars after cooking. The effect of freezing on the volatile fraction was presented based on the Brussels sprout cultivars. Most of the changes were closely related to the activity of the lipoxygenase (LOX) pathway enzymes. These are characterized by a marked reduction in alcohol contents and an increment in aldehyde contents. Moreover, important changes were noted in the concentrations of bioactive components, e.g., isothiocyanates. This research included a large set of samples consisting of many cultivars of each analyzed vegetable, which is why it provides a considerable body of general information concerning volatiles in Brassica vegetables.
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Staszek, Dorota, Marta Orłowska, Józef Rzepa, Michał S. Wróbel, Teresa Kowalska, Grażyna Szymczak y Monika Waksmundzka-Hajnos. "Fingerprinting of the Volatile Fraction from Selected Thyme Species by Means of Headspace Gas Chromatography with Mass Spectrometric Detection". Journal of AOAC INTERNATIONAL 97, n.º 5 (1 de septiembre de 2014): 1250–58. http://dx.doi.org/10.5740/jaoacint.sgestaszek.
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Abstract The Thymus genus has a firm position in Mediterranean folk medicine and culinary tradition, and yet certain confusion is observed in its botanical taxonomy. Therefore, chemical analysis of secondary metabolites and selection of reliable chemotaxonomic markers can prove helpful. In this study, the volatile fraction derived from 20 different thyme specimens was analyzed by means of headspace GC with MS detection. From the obtained chromatographic fingerprints, the diversity of the volatile fraction originating from the different thyme species clearly emerged. Identification of volatile components was based on a software library of mass spectra. There was only one common component derived from all 20 investigated thyme species, i.e., ß-linalool. For three different Thymus species, a comparison was made of the performance of the headspace extraction and hydrodistillation. Characteristic differences in composition of the volatile fraction obtained with use of these two techniques were discussed. Finally, the obtained chromatographic fingerprints of the volatile fraction were analyzed by means of a chemometric approach (principal component analysis), in order to trace similarities in their chemical composition.
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Trebukhov, S. A., V. N. Volodin, O. V. Ulanova, A. V. Nitsenko y N. M. Burabaeva. "Thermodynamics of formation and evaporation of lead-tin alloys". Kompleksnoe ispolʹzovanie mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik shikisattardy Keshendi Paidalanu 316, n.º 1 (15 de marzo de 2021): 82–90. http://dx.doi.org/10.31643/2021/6445.10.
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Only a few works have been devoted to thermodynamic studies of the lead-tin system by methods including the volatile components evaporation process. When the binary system is separated into metals by distillation, the volatile component is removed from the alloy and the low-volatile component accumulates in the bottom products, that is, there are alloy composition changes over the entire concentration range. It is necessary to know the boundaries position of the melt and vapor coexistence fields on the state diagram, especially for solutions beneficiated with non-volatile metal to assess the quality of the vapor phase by the content of the low-volatile component. In this regard, the study has been completed with the purpose to clarify the values of the thermodynamic functions of the formation and evaporation of lead-tin melts required to calculate the boundaries of the liquid and vapor coexistence fields on the state diagram that enables us to judge the amount of a low-volatile component in the vapor phase under equilibrium conditions. The thermodynamic activity of lead was calculated, as well as the numerical integration of the Gibbs-Duhem equation using the substitution proposed by Darken is the thermodynamic activity and pressure of saturated tin vapor Based on the values of the saturated lead vapor pressure, determined by the boiling point method (isothermal version) for alloys predominantly of the lead edge of the phase diagram. The thermodynamic constants thus obtained will add to the base of physicochemical data and will be used to calculate the boundaries of the vapor-liquid equilibrium fields on the phase diagram, allowing to determine the possibility and completeness of the distillation separation of metals.
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Ho, Chia-Hsun, Man-Hsia Yang y Huey-Ling Lin. "Temperature and Different Organs Create Volatile Profile Differences of Edible Gynura [Gynura bicolor (Roxb. ex Willd.) DC]". HortScience 56, n.º 8 (agosto de 2021): 954–60. http://dx.doi.org/10.21273/hortsci15851-21.
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The volatile profile of the edible vegetable Gynura bicolor [Gynura bicolor (Roxb. ex Willd.) DC] was analyzed using gas chromatography-mass spectrometry (GC-MS). Isocaryophyllene (23.2%), α-pinene (16.8%), α-humulene (9.1%), β-pinene (7.3%), and copaene (7.0%) were identified as the major compounds in the leaves. In the stems, α-pinene (27.1%), β-pinene (13.0%), isocaryophyllene (7.8%), β-myrceneb (7.8%), 1-undecene (5.7%), and copaene (5.3%) were the main components. G. bicolor grows best at 25 °C. When cultivated at different temperatures (20 to 35 °C in incements of 5 °C), the volatile profiles shifted. The proportion of isocaryophyllene was lower at 20 °C than at the other temperatures. The relative amounts of α-pinene and α-humulene were highest at 20 °C, whereas copaene was highest at 35 °C. Principal component analysis (PCA) was used to explore the correlation between volatile compounds identified from the vegetative tissues and temperature treatments. It reveals the same trend with the previous statements and the first principal component (PC1) and the second principal component (PC2) explains up to 90% of the variance. Experimental results revealed that both temperature and vegetative organ correlate with the volatile emission profile of G. bicolor.
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Cozzolino, Rosaria, Matteo Stocchero, Rosa Perestrelo y José S. Câmara. "Comprehensive Evaluation of the Volatomic Fingerprint of Saffron from Campania towards Its Authenticity and Quality". Foods 11, n.º 3 (27 de enero de 2022): 366. http://dx.doi.org/10.3390/foods11030366.
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The volatile profiles of eight saffron samples (seven cultivated and one spontaneous) grown in different geographical districts within the Campania region (southern Italy) were compared. Using headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS-SPME/GC-MS), overall, 80 volatiles were identified in the eight landraces. Among them, safranal and its isomers and other related compounds such as isophorones, which are not only key odorants but also pharmacologically active metabolites, have been detected in all the investigated samples. Principal Component Analysis performed on the volatiles’ compounds revealed that the spontaneous sample turned out to be an outlier. In particular, the volatile organic compounds (VOCs) profile of the spontaneous saffron presented four lilac aldehydes and four lilac alcohol isomers, which, to the authors’ knowledge, have never been identified in the volatile signature of this spice. The multivariate statistical analysis allowed the discrimination of the seven cultivate saffron ecotypes in four well-separated clusters according to variety. Moreover, 20 VOCs, able to differentiate the clusters in terms of single volatile metabolite, were discovered. Altogether, these results could contribute to identifying possible volatile signature metabolites (biomarkers) or patterns that discriminate saffron samples grown in Campania region on a molecular basis, encouraging future biodiversity programs to preserve saffron landraces revealing valuable genetic resources.
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Wang, Aixia, Songfeng Xie, Zengrun Xia, Fengzhong Wang y Litao Tong. "Further Interpretation of the Volatile, Microbial Community and Edible Quality of Fresh Fermented Rice Noodles with Different Selected Strains". Foods 12, n.º 5 (24 de febrero de 2023): 961. http://dx.doi.org/10.3390/foods12050961.
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Understanding bacteria and yeasts can reduce unpredictable changes in fresh fermented rice noodles (FFRN). The effects of selected strains (Limosilactobacillus fermentum, Lactoplantibacillus plantarum, Lactococcus lactis and Saccharomyces cerevisiae) on the edible quality, microbial community, and volatile component of FFRN were studied. The results indicated that the fermentation time could be shortened to 12 h when Limosilactobacillus fermentum, Lactoplantibacillus plantarum, and Lactococcus lactis were added, whereas it still required approximately 42 h after adding Saccharomyces cerevisiae. Only a steady bacterial composition was provided by adding Limosilactobacillus fermentum, Lactoplantibacillus plantarum, and Lactococcus lactis, and only a steady fungal composition was provided by adding Saccharomyces cerevisiae. Therefore, these microbial results indicated that the selected single strains cannot improve the safety of FFRN. However, the cooking loss was decreased from 3.11 ± 0.11 to 2.66 ± 0.13 and the hardness of FFRN was increased from 1186 ± 178 to 1980 ± 207 when it was fermented with single strains. Finally, a total of 42 volatile components were determined by Gas chromatography-ion Mobility Spectrometry and 8 aldehydes, 2 ketones, and 1 alcohol were added during the entire fermentation process. The main volatile components were different during fermentation depending on the added strain, and there was the greatest variety of volatiles in the group with added Saccharomyces cerevisiae.
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Nori-Shargh, D., H. Norouzi-Arasi, S. Mohammadi, M. Mirza y K. Jaimand. "Volatile Component ofMentha longifolia(L.) Huds. from Iran". Journal of Essential Oil Research 12, n.º 1 (enero de 2000): 111–12. http://dx.doi.org/10.1080/10412905.2000.9712056.
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Khukhryansky, Yu y V. Emelyanov. "Kinetics of volatile component evaporation from solution-melt". Heat and Mass Transfer 37, n.º 2-3 (27 de abril de 2001): 191–96. http://dx.doi.org/10.1007/s002310000183.
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Zhang, Qingquan, Xiaojun Liu, Dayu Liu y Hongwei Gai. "Ultra-small droplet generation via volatile component evaporation". Lab on a Chip 14, n.º 8 (2014): 1395. http://dx.doi.org/10.1039/c3lc51183a.
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Zhang, Haipeng, Huan Wen, Jiajing Chen, Zhaoxin Peng, Meiyan Shi, Mengjun Chen, Ziyu Yuan, Yuan Liu, Hongyan Zhang y Juan Xu. "Volatile Compounds in Fruit Peels as Novel Biomarkers for the Identification of Four Citrus Species". Molecules 24, n.º 24 (12 de diciembre de 2019): 4550. http://dx.doi.org/10.3390/molecules24244550.
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The aroma quality of citrus fruit is determined by volatile compounds, which bring about different notes to allow discrimination among different citrus species. However, the volatiles with various aromatic traits specific to different citrus species have not been identified. In this study, volatile profiles in the fruit peels of four citrus species collected from our previous studies were subjected to various analyses to mine volatile biomarkers. Principal component analysis results indicated that different citrus species could almost completely be separated. Thirty volatiles were identified as potential biomarkers in discriminating loose-skin mandarin, sweet orange, pomelo, and lemon, while 17 were identified as effective biomarkers in discriminating clementine mandarins from the other loose-skin mandarins and sweet oranges. Finally, 30 citrus germplasms were used to verify the classification based on β-elemene, valencene, nootkatone, and limettin as biomarkers. The accuracy values were 90.0%, 96.7%, 96.7%, and 100%, respectively. This research may provide a novel and effective alternative approach to identifying citrus genetic resources.
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Khokhlov, Yu S., I. A. Fedotova y O. M. Shevchuk. "Changes in the component composition of Thymus vulgaris L. essential oil depending on the method of distillation". Plant Biology and Horticulture: theory, innovation, n.º 154 (21 de octubre de 2020): 106–15. http://dx.doi.org/10.36305/2712-7788-2020-1-154-106-115.
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The objective of the work was to identify changes in the amount and component composition of essential oil in the raw material of Thymus vulgaris L. (common thyme) when using different distillation methods. The object of the study was two samples of thyme-thymol and linalool chemotypes. Essential oil was obtained from freshly harvested raw materials (inflorescences in the mass flowering phase) by the following methods: hydrodistillation method on Clevenger apparatuses and steam extraction method on the installation for the production of essential oil and intermediates "Alpha-Ether Compact". The component composition of volatile substances was determined by gas chromatography-mass spectrometry. In the composition of volatile compounds of plant essential oil, 29 components for the thymol chemotype were identified, and 18 components for the linalool chemotype were identified. It was found that the use of the hydrodistillation method allows extracting 40-50% more essential oil. Significant differences were found between the mass fraction of extracted essential oil components using different methods and the content of the mass fraction of essential oil in the raw material of Th. vulgaris and found that depending on the method of obtaining essential oil, the proportion of volatile terpene hydrocarbons and oxygen-containing compounds changes. The method of steam distillation leads to a deterioration of the component composition of the essential oil, reducing the content of the dominant components of both chemotypes (thymol and linalool).
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He, Shan, Bin Zhang, Xuan Dong, Yuqing Wei, Hongtu Li y Bo Tang. "Differentiation of Goat Meat Freshness Using Gas Chromatography with Ion Mobility Spectrometry". Molecules 28, n.º 9 (4 de mayo de 2023): 3874. http://dx.doi.org/10.3390/molecules28093874.
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To investigate the flavor changes in goat meat upon storage, the volatile components observed in goat meat after different storage periods were determined using gas chromatography–ion mobility spectrometry (GC–IMS). A total of 38 volatile organic compounds (VOCs) were determined from the goat meat samples, including alcohols, ketones, aldehydes, esters, hydrocarbons, ethers, and amine compounds. 1-Hexanol, 3-Hydroxy-2-butanone, and Ethyl Acetate were the main volatile substances in fresh goat meat, and they rapidly decreased with increasing storage time and can be used as biomarkers for identifying fresh meat. When combined with the contents of total volatile basic–nitrogen (TVB-N) and the total numbers of bacterial colonies observed in physical and chemical experiments, the characteristic volatile components of fresh, sub-fresh, and spoiled meat were determined by principal component analysis (PCA). This method will help with the detection of fraudulent production dates in goat meat sales.
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Qiao, Yening, Jinfeng Bi, Qinqin Chen, Xinye Wu, Min Gou, Haonan Hou, Xinwen Jin y Giorgia Purcaro. "Volatile Profile Characterization of Winter Jujube from Different Regions via HS-SPME-GC/MS and GC-IMS". Journal of Food Quality 2021 (30 de agosto de 2021): 1–15. http://dx.doi.org/10.1155/2021/9958414.
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A combined untargeted and targeted approach was established for fingerprinting volatile organic compounds in winter jujubes from eight regions of China. Volatiles, including alcohols, aldehydes, acids, esters, and alkenes, were identified by gas chromatography-ion mobility spectrometry (GC-IMS). Benzyl alcohol, octanoic acid, 2-hexenal, linalool, 2-nonenal, and ethyl decanoate were the most common compounds present in all jujubes. Principal component analysis (PCA) from GC-IMS and untargeted E-nose showed that the main volatile organic compounds (VOCs) of most jujubes were similar. The volatile organic compounds of winter jujubes from Yuncheng city, Shanxi province, and Aksu region, Xinjiang province, were significantly different from those from other regions. 1-Penten-3-ol, ethyl hexanoate, methyl laurate, and 2-formyltoluene were the markers of XJAKS with green and fruity aroma, and SXYC could be labeled by acetone and 2-methoxyphenol with woody and pungent aroma. GC-IMS was an effective method for volatile fingerprinting of jujubes with high sensitivity and accuracy.
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Yates, David I., Bonnie H. Ownley, Nicole Labbé, Joseph J. Bozell, William E. Klingeman, Emma K. Batson y Kimberly D. Gwinn. "Sciadopitys verticillata Resin: Volatile Components and Impact on Plant Pathogenic and Foodborne Bacteria". Molecules 24, n.º 20 (19 de octubre de 2019): 3767. http://dx.doi.org/10.3390/molecules24203767.
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Sciadopitys verticillata (Sv) produces a white, sticky, latex-like resin with antimicrobial properties. The aims of this research were to evaluate the effects of this resin (Sv resin) on bacterial populations and to determine the impact of its primary volatile components on bioactivity. The impact of sample treatment on chemical composition of Sv resin was analyzed using Fourier transform infrared spectroscopy (FTIR) coupled with principal component analysis. The presence and concentration of volatiles in lyophilized resin were determined using gas chromatography/mass spectrometry (GC/MS). Changes in bacterial population counts due to treatment with resin or its primary volatile components were monitored. Autoclaving of the samples did not affect the FTIR spectra of Sv resin; however, lyophilization altered spectra, mainly in the CH and C=O regions. Three primary bioactive compounds that constituted >90% of volatiles (1R-α-pinene, tricyclene, and β-pinene) were identified in Sv resin. Autoclaved resin impacted bacterial growth. The resin was stimulatory for some plant and foodborne pathogens (Pseudomonas fluorescens, P. syringae, and Xanthomonas perforans) and antimicrobial for others (Escherichia coli, Bacillus cereus, Agrobacterium tumefaciens, and Erwinia amylovora). Treatment with either 1R-α-pinene or β-pinene reduced B. cereus population growth less than did autoclaved resin. The complex resin likely contains additional antimicrobial compounds that act synergistically to inhibit bacterial growth.
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Al-Fatimi, Mohamed. "β-Caryophyllene: A Single Volatile Component of n-Hexane Extract of Dracaena cinnabari Resin". Molecules 25, n.º 21 (26 de octubre de 2020): 4939. http://dx.doi.org/10.3390/molecules25214939.
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The pure Soqotri resin of Dracaena cinnabari Balf.f. (Dracaenaceae) has no volatile smell due to its low content of volatile constituents. Although it is insoluble in n-Hexane, we found that the resin, when suspended in n-Hexane within five days at 5 °C, led to the extraction of a small portion of a single volatile liquid constituent, which was identified by GC-MS as sesquiterpene β-caryophyllene. This method of extracting the volatile constituents using hexane under cooling is very suitable for resins of the Dracaena species because these resins usually contain very few volatile terpenes and/or non-terpenes, and they may contain only one volatile terpene per resin as this study result. β-Caryophyllene was identified and separated for the first time from the Soqotri standard resin of Dracaena cinnabari. Therefore, β-caryophyllene, as a new chemical property, can support to evaluate the purity of the Soqotri resin. Moreover, a big mass of D. cinnabari resin can yield concentrated β-caryophyllene as a liquid extract for further pharmaceutical and nutraceutical applications.
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Cui, Bei, Tao Zheng, Ping Deng, Sheng Zhang y Zhong Zhao. "Chemotaxonomic Variation in Volatile Component Contents in Ancient Platycladus orientalis Leaves with Different Tree Ages in Huangdi Mausoleum". Molecules 28, n.º 5 (22 de febrero de 2023): 2043. http://dx.doi.org/10.3390/molecules28052043.
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To gain insight into the differences in the composition and volatile components content in ancient Platycladus orientalis leaves with different tree ages in Huangdi Mausoleum, the volatile components were identified by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS–SPME–GC–MS) method. The volatile components were statistically analyzed by orthogonal partial least squares discriminant analysis and hierarchical cluster analysis, and the characteristic volatile components were screened. The results exhibited that a total of 72 volatile components were isolated and identified in 19 ancient Platycladus orientalis leaves with different tree ages, and 14 common volatile components were screened. Among them, the contents of α-pinene (6.40–16.76%), sabinene (1.11–7.29%), 3-carene (1.14–15.12%), terpinolene (2.17–4.95%), caryophyllene (8.04–13.53%), α-caryophyllene (7.34–14.41%), germacrene D (5.27–12.13%), (+)-Cedrol (2.34–11.30%) and α-terpinyl acetate (1.29–25.68%) were relatively higher (>1%), accounting for 83.40–87.61% of the total volatile components. Nineteen ancient Platycladus orientalis trees were clustered into three groups through the HCA method based on the 14 common volatile components content. Combined with the results of OPLS–DA analysis, (+)-cedrol, germacrene D, α-caryophyllene, α-terpinyl acetate, caryophyllene, β-myrcene, β-elemene and epiglobulol were the differential volatile components to distinguish ancient Platycladus orientalis with different tree ages. The results revealed that the composition of the volatile components in ancient Platycladus orientalis leaves with different tree ages was different, showing different aroma characteristics, which provided a theoretical reference for the differential development and application of volatile components in ancient Platycladus orientalis leaves.
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Wang, Jie, Xiaohan Li, Ying Wu, Fengfeng Qu, Lei Liu, Baoyi Wang, Peiqiang Wang y Xinfu Zhang. "HS−SPME/GC−MS Reveals the Season Effects on Volatile Compounds of Green Tea in High−Latitude Region". Foods 11, n.º 19 (28 de septiembre de 2022): 3016. http://dx.doi.org/10.3390/foods11193016.
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This study investigates the volatile compounds of green tea produced with different leaves from spring, summer, and autumn in high−latitude region. A total of 95 volatile compounds were identified by gas chromatography–mass spectrometry (GC–MS). Spring, summer and autumn green tea contained 68, 72 and 82 volatile compounds, respectively. Principal component analysis (PCA), partial least squares−discrimination analysis (PLS−DA), and hierarchical cluster analysis (HCA) classified the samples and showed the difference. And 32 key characteristic components were screened out based on variable importance in the projection (VIP) values higher than 1.0. The characteristic volatile compounds of spring green tea including 18 components, such as geranylacetone, phenethyl alcohol, geraniol, β−ionone, jasmone, 1−octen−3−ol and longifolene. 13 components such as 2−methylfuran, indole, 1−octanol, D−limonene and ethanethiol were the key compounds in summer green tea. And 2,4,6−trimethylstyrene was the major differential volatile compounds in autumn green tea. The results increase our knowledge of green tea in different seasons and provide a theoretical basis for production control of green tea.
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González-Domínguez, Raúl, Ana Sayago, Ikram Akhatou y Ángeles Fernández-Recamales. "Volatile Profiling of Strawberry Fruits Cultivated in a Soilless System to Investigate Cultivar-Dependent Chemical Descriptors". Foods 9, n.º 6 (11 de junio de 2020): 768. http://dx.doi.org/10.3390/foods9060768.
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Volatile compounds are essential for food organoleptic characteristics and of great utility for the food industry as potential markers for authenticity purposes (e.g., variety, geographical origin, adulteration). The aim of this study was to determine the characteristic volatile compounds of strawberry samples grown in a soilless system by using headspace solid phase micro-extraction coupled with gas chromatography and to investigate the influence of cultivar (Festival, Candonga, Camarosa) on this volatile profile. We observed that Festival and, to a lesser extent, Candonga varieties were characterized by the richest aroma-related profiles, including higher levels of esters, furanones and terpenes. In particular, methyl butyrate, hexyl hexanoate, linalool, geraniol and furaneol were the most abundant aromatic compounds detected in the three varieties of strawberries. Complementarily, the application of pattern recognition chemometric approaches, including principal component analysis and linear discriminant analysis, demonstrated that concentrations of specific volatiles can be employed as chemical descriptors to discriminate between strawberry cultivars. Accordingly, geraniol and hexyl hexanoate were found to be the most significant volatiles for the discrimination of strawberry varieties.
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Xie, Long, Yu-Si Jiang, Yu-Bin Wang, Hong-Wei Xiao, Wei Liu, Yue Ma y Xiao-Yan Zhao. "Changes in the Physical Properties and Volatile Odor Characteristics of Shiitake Mushrooms (Lentinula edodes) in Far Infrared Radiation Drying". Foods 12, n.º 17 (25 de agosto de 2023): 3213. http://dx.doi.org/10.3390/foods12173213.
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The effects of far infrared radiation drying (FID) on physical properties (drying kinetics, color, shrinkage ratio, rehydration ratio, and microstructural characterization) and volatile odor characteristics (volatile odor profile distinction and volatile compounds) of shiitake mushrooms were evaluated in this study. During the FID, the drying time decreased with the increase in drying temperature, and it had a less significant effect in the lower temperature range. The increase in drying temperature led to increasing shrinkage and collapse in the microstructure, resulting in a decreased rehydration rate and highlighting the influence of microstructure characteristics on macroscopic properties. Higher drying temperatures employed in the FID process were found to be associated with a decreasing L* value and an increasing ΔE value. The application of principal component analysis can effectively distinguish the significant effect of FID on the volatile odor profiles of shiitake mushrooms. Compared to raw shiitake mushrooms, FID treatment has endowed samples with a greater variety of volatile compounds. After processing with FID, there have been increases in volatile components such as sulfur compounds, acids, nitrogen compounds, and aldehydes, while volatile components like alcohols, ketones, and hydrocarbons have shown decreases.