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1.
Sensors (Basel) ; 21(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206361

RESUMO

Tea is the second most consumed beverage, and its aroma, determined by volatile compounds (VOCs) present in leaves or developed during the processing stages, has a great influence on the final quality. The goal of this study is to determine the volatilome of different types of tea to provide a competitive tool in terms of time and costs to recognize and enhance the quality of the product in the food chain. Analyzed samples are representative of the three major types of tea: black, green, and white. VOCs were studied in parallel with different technologies and methods: gas chromatography coupled with mass spectrometer and solid phase microextraction (SPME-GC-MS) and a device called small sensor system, (S3). S3 is made up of tailor-made metal oxide gas sensors, whose operating principle is based on the variation of sensor resistance based on volatiloma exposure. The data obtained were processed through multivariate statistics, showing the full file of the pre-established aim. From the results obtained, it is understood how supportive an innovative technology can be, remotely controllable supported by machine learning (IoF), aimed in the future at increasing food safety along the entire production chain, as an early warning system for possible microbiological or chemical contamination.


Assuntos
Compostos Orgânicos Voláteis , Internet , Odorantes/análise , Óxidos , Microextração em Fase Sólida , Chá , Compostos Orgânicos Voláteis/análise
2.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202706

RESUMO

Espresso coffee (EC) is a common coffee preparation technique that nowadays is broadly widespread all over the globe. Its popularity is in part attributed to the intense aroma and pleasant flavor. Many researchers have studied and reviewed the aroma of the coffee, but there is a lack of specific review focused on EC aroma profile even if it is intensively investigated. Thus, the objective of the current review was to summarize the aroma profile of EC and how different preparation variables can affect EC flavor. Moreover, a collection of diverse analytical procedures for volatile analysis was also reported. The findings of this survey showed that the volatile fraction of EC is extremely complex, but just some compounds are responsible for the characteristic aroma of the coffee, such as some aldehyde, ketones, furanones, furans, sulfur compounds, pyrazines, etc. In addition, during preparation, some variables, e.g., temperature and pressure of water, granulometry of the coffee particle, and brew ratio, can also modify the aroma profile of this beverage, and therefore its quality. A better understanding of the aroma fraction of EC and how the preparation variables should be adjusted according to desired EC would assist coffee workers in obtaining a higher quality product.


Assuntos
Café/química , Temperatura Alta , Odorantes/análise , Compostos Orgânicos Voláteis/análise
3.
Molecules ; 26(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34198992

RESUMO

Wet coffee processing generates a large amount of coffee pulp waste that is mostly disposed of in the processing units. To reduce this waste and the associated environmental burden, an alternative strategy would be to exploit the coffee pulp to produce a durable and stable consumable product. Accordingly, a puree produced from Robusta coffee pulp was investigated in relation to its physicochemical and sensory properties. After thermal and chemical stabilization, the obtained puree (pH 3.6) was found to exhibit a multimodal particle size distribution, shear-thinning behavior, and lower discoloration, as well as an antioxidant capacity of 87.9 µmolTE/gDM. The flavor of the puree was examined by sensory evaluation and the corresponding analyses of aroma-active volatile compounds, as determined using aroma extract dilution analyses (AEDA) and gas chromatography-mass spectrometry/olfactometry (GC-MS/O). The puree was characterized by dominant fruity (4.4), floral (3.4), citrusy (3.3) and hay-like (3.3) odor impressions. The aroma-active compounds were predominantly aldehydes, acids, and lactones, whereby (E)-ß-damascenone, geraniol, 4-methylphenol, 3-hydroxy-4,5-dimethylfuran-2(5H)-one, and 4-hydroxy-3-methoxybenzaldehyde exhibited the highest flavor dilution (FD) factor (1024), thereby indicating their high impact on the overall aroma of the puree. This study demonstrates an approach to stabilize coffee pulp to produce a sweet, fruity puree with comparable physical properties to other fruit purees and that can be used as a new and versatile flavoring ingredient for various food applications.


Assuntos
Café/química , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Café/classificação , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Olfatometria , Extratos Vegetais/análise , Extratos Vegetais/química , Compostos Orgânicos Voláteis/química
4.
Sensors (Basel) ; 21(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200440

RESUMO

Volatile organic compounds (VOCs) are chemicals emitted by various groups, such as foods, bacteria, and plants. While there are specific pathways and biological features significantly related to such VOCs, detection of these is achieved mostly by human odor testing or high-end methods such as gas chromatography-mass spectrometry that can analyze the gaseous component. However, odor characterization can be quite helpful in the rapid classification of some samples in sufficient concentrations. Lower-cost metal-oxide gas sensors have the potential to allow the same type of detection with less training required. Here, we report a portable, battery-powered electronic nose system that utilizes multiple metal-oxide gas sensors and machine learning algorithms to detect and classify VOCs. An in-house circuit was designed with ten metal-oxide sensors and voltage dividers; an STM32 microcontroller was used for data acquisition with 12-bit analog-to-digital conversion. For classification of target samples, a supervised machine learning algorithm such as support vector machine (SVM) was applied to classify the VOCs based on the measurement results. The coefficient of variation (standard deviation divided by mean) of 8 of the 10 sensors stayed below 10%, indicating the excellent repeatability of these sensors. As a proof of concept, four different types of wine samples and three different oil samples were classified, and the training model reported 100% and 98% accuracy based on the confusion matrix analysis, respectively. When the trained model was challenged against new sets of data, sensitivity and specificity of 98.5% and 98.6% were achieved for the wine test and 96.3% and 93.3% for the oil test, respectively, when the SVM classifier was used. These results suggest that the metal-oxide sensors are suitable for usage in food authentication applications.


Assuntos
Nariz Eletrônico , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Aprendizado de Máquina , Odorantes/análise , Compostos Orgânicos Voláteis/análise
5.
J Agric Food Chem ; 69(23): 6588-6600, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34085519

RESUMO

The whole sensometabolome of a typical dairy milk dessert was decoded to potentially serve as a blueprint for further flavor optimization steps of functional fat-reduced food. By applying the sensomics approach, a wide range of different dairy volatiles, semi and nonvolatiles, were analyzed by ultrahigh-performance liquid chromatography tandem mass spectrometry with or without derivatization presteps. While for volatile sulfur compounds with low odor thresholds, headspace solid-phase microextraction gas chromatography was established, abundant carbohydrates and organic acids were quantified by quantitative 1H nuclear magnetic resonance spectroscopy. Validated quantitation, sensory reconstitution, and omission studies highlighted eight flavor-active compounds, namely, diacetyl, δ-tetra-, δ-hexa-, and δ-octadecalactone, sucrose, galactose, lactic acid, and citric acid as indispensable for flavor recombination. Furthermore, eight odorants (acetaldehyde, acetic acid, butyric acid, methanethiol, phenylacetic acid, dimethyl sulfide, acetoin, and hexanoic acid), all with odor activity values >1, additionally contributed to the overall flavor blueprint. Within this work, a dairy flavor analytical toolbox covering four different high-throughput methods could successfully be established showing potential for industrial applications.


Assuntos
Aromatizantes , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Microextração em Fase Sólida , Paladar , Compostos Orgânicos Voláteis/análise
6.
Molecules ; 26(9)2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34064526

RESUMO

The volatile compounds from insects (Tenebrio molitor and Zophobas morio larvae) roasted at 160, 180, or 200 °C and fed with potato starch or blue corn flour were isolated by solid-phase microextraction (SPME), and identified by gas chromatography-mass spectrometry (GC-MS). In the tested material, 48 volatile compounds were determined. Among them, eight are pyrazines, aroma compounds that are formed in food products during thermal processing due to the Maillard reaction. Eleven of the identified compounds influenced the roast, bread, fat, and burnt aromas that are characteristic for traditional baked dishes (meat, potatoes, bread). Most of them are carbonyl compounds and pyrazines. To confirm the contribution of the most important odorants identified, their odor potential activity values (OAVs) and %OAV were calculated. The highest value was noted for isobuthylpyrazine, responsible for roast aroma (%OAV > 90% for samples roasted at lower temperatures), and 2,5-dimethylpyrazine, responsible for burnt aroma (%OAV > 20% for samples roasted at the highest temperature). According to the study, the type of feed did not significantly affect the results of the sensory analysis of roasted insects. The decisive influence was the roasting temperature. The highest scores were achieved for Tenebrio molitor larvae heat-treated at 160 °C.


Assuntos
Besouros/química , Culinária , Sensação , Tenebrio/química , Animais , Cromatografia Gasosa-Espectrometria de Massas , Larva/química , Odorantes/análise , Solanum tuberosum , Amido , Perda Insensível de Água
7.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068329

RESUMO

Anthurium is an important ornamental crop in the world market and its floral scent can enhance its ornamental value. To date, studies of the components and formation mechanism of the floral scent of Anthurium are relatively few. In this study, the scent profiles of two Anthurium varieties were measured by gas chromatograph-mass spectrometer (GC-MS). There were 32 volatile organic compounds (VOCs) identified in Anthurium 'Mystral', and the most abundant compound was eucalyptol (57.5%). Extremely small amounts of VOCs were detected in Anthurium 'Alabama'. Compared with A. 'Alabama', most genes related to floral scent synthesis exhibited a higher expression in A.'Mystral', including AaDXS, AaDXR, AaMDS, AaHDS, AaTPS, AaDAHPS, AaADT2, AaPAL1, and AaPAL2. In order to produce new varieties of Anthurium with fragrance, 454 progenies of two crossbred combinations of A. 'Mystral' and A. 'Alabama' were obtained. Four F1 generation plants with different floral scent intensities were selected for further study. The major components of floral scent in the progenies were similar to that of the parental A.'Mystral' plant. The expression patterns of genes related to floral scent synthesis were consistent with the relative contents of different types of VOCs. This study revealed the profiles of volatile compounds and associated gene expression in two Anthurium cultivars and their F1 hybrids, which provided a basis for the floral scent inheritance of Anthurium andraeanum.


Assuntos
Araceae/genética , Cruzamentos Genéticos , Regulação da Expressão Gênica de Plantas , Hibridização Genética , Compostos Orgânicos Voláteis/análise , Vias Biossintéticas/genética , Segregação de Cromossomos/genética , Flores/química , Inflorescência/genética , Odorantes/análise , Fenótipo
8.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068432

RESUMO

This study investigates for the first time the role of fructans with prebiotic effects (oligofructose and inulin) on retronasal aroma among elderly individuals. The impact of oligofructose (20% w/w) on retronasal aroma release was investigated using proton transfer reaction-mass spectrometry (PTR-MS) after 73 elderly individuals consumed aqueous solutions aromatized with five aroma compounds (pentan-2-one, nonan-2-one, hexan-2,3-dione, octanal and linalool). The influence of oligofructose and inulin (10% w/w) on the perceived intensity (n = 26) of two aroma descriptors (butter and floral) was also studied together with the possibility of a dumping effect on aroma evaluation due to the sweetness provided by the fructans. The results showed that the presence of oligofructose produced a significant reduction in retronasal aroma release, which could be generally explained by the physicochemical properties of aroma compounds. The presence of prebiotic fructans did not significantly affect the perceived intensity of butter and floral notes, although a dumping effect for the butter descriptor in the presence of oligofructose was observed. To conclude, these findings suggest that although fructans can exert an impact on retronasal aroma, they can be used at precise concentrations to increase the prebiotic fibre content of food products without affecting the aroma profile of foods.


Assuntos
Frutanos/farmacologia , Nariz/fisiologia , Odorantes/análise , Prebióticos , Idoso , Manteiga , Feminino , Flores , Humanos , Masculino , Oligossacarídeos/farmacologia
9.
Molecules ; 26(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064882

RESUMO

Paratuberculosis is an important disease of ruminants caused by Mycobacterium avium ssp. paratuberculosis (MAP). Early detection is crucial for successful infection control, but available diagnostic tests are still dissatisfying. Methods allowing a rapid, economic, and reliable identification of animals or herds affected by MAP are urgently required. This explorative study evaluated the potential of volatile organic compounds (VOCs) to discriminate between cattle with and without MAP infections. Headspaces above fecal samples and alveolar fractions of exhaled breath of 77 cows from eight farms with defined MAP status were analyzed in addition to stable air samples. VOCs were identified by GC-MS and quantified against reference substances. To discriminate MAP-positive from MAP-negative samples, VOC feature selection and random forest classification were performed. Classification models, generated for each biological specimen, were evaluated using repeated cross-validation. The robustness of the results was tested by predicting samples of two different sampling days. For MAP classification, the different biological matrices emitted diagnostically relevant VOCs of a unique but partly overlapping pattern (fecal headspace: 19, alveolar gas: 11, stable air: 4-5). Chemically, relevant compounds belonged to hydrocarbons, ketones, alcohols, furans, and aldehydes. Comparing the different biological specimens, VOC analysis in fecal headspace proved to be most reproducible, discriminatory, and highly predictive.


Assuntos
Ar , Fezes/química , Gases/análise , Odorantes/análise , Paratuberculose/diagnóstico , Alvéolos Pulmonares/metabolismo , Animais , Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/microbiologia , Curva ROC , Reprodutibilidade dos Testes , Compostos Orgânicos Voláteis/análise
10.
J Agric Food Chem ; 69(25): 6943-6957, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34143625

RESUMO

The aroma of a wine is mostly driven by not only the factors in the vineyard, such as the grape variety and harvest time, but also the fermentation process. Icewine is a unique, intensely sweet wine made from late harvested grapes that have frozen naturally on the vine. Different from normal table wines, the grapes used in icewine naturally undergo a dehydration process and freeze-thaw cycles, and the must for icewine making has to be pressed from frozen grapes. This pressing process leaves water behind as ice crystals and allows the grape juice to be concentrated with more sugars, acids, and other dissolved solids, resulting in a slower than normal fermentation. These special procedures can lead to a unique aroma characteristic of icewine. This review delves into recent advances in chemical compounds related to icewine aroma characteristics and addresses how changes in these aroma characteristics and composition are influenced by environmental, viticultural, and oenological factors in the vineyard and winery. Deficiencies in previous studies and future trends related to the flavor science of icewine were also briefly addressed.


Assuntos
Vitis , Compostos Orgânicos Voláteis , Vinho , Fermentação , Odorantes/análise , Paladar , Compostos Orgânicos Voláteis/análise , Vinho/análise
11.
Molecules ; 26(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072807

RESUMO

Peanut oil is favored by consumers due to its rich nutritional value and unique flavor. This study used headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) to examine the differences in the peanut oil aroma on the basis of variety, roasting temperatures, and pressing components. The results revealed that the optimal conditions for extracting peanut oil were achieved through the use of 50/30 µm DVB/CAR/PDMS fibers at 60 °C for 50 min. The primary compounds present in peanut oil were pyrazines. When peanuts were roasted, the temperature raised from 120 °C to 140 °C and the content of aldehydes in peanut oil increased; however, the content of aldehydes in No. 9 oil at 160 °C decreased. The components of peanut shell oil varied depending on the peanut variety. The most marked difference was observed in terms of the main compound at the two roasting temperatures. This compound was a pyrazine, and the content increased with the roasting temperature in hekei oils. When the roasting temperature was lower, No. 9 oil contained more fatty acid oxidation products such as hexanal, heptanal, and nonanal. When the roasting temperature increased, No. 9 oil contained more furfural and 5-methylfurfural. Heren oil was easier to oxidize and produced nonanal that possessed a fatty aroma.


Assuntos
Análise de Alimentos/métodos , Óleo de Amendoim/metabolismo , Microextração em Fase Sólida/métodos , Aldeídos/análise , Arachis/química , Aromatizantes/análise , Furaldeído/análogos & derivados , Furaldeído/análise , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Teste de Materiais , Odorantes/análise , Óleo de Amendoim/química , Pirazinas/química , Paladar , Temperatura , Compostos Orgânicos Voláteis/análise
12.
Plant Sci ; 309: 110959, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34134850

RESUMO

Floral scent is an important trait that has a significant influence on the reproduction of many flowering plants and the market value of several ornamental crops. The family of Asteraceae is well known for its unique floral structure (capitulum) that consists of many florets. Although the constituents of either floral essential oils or emitted floral volatiles have been reported in many species of Asteraceae, little information is available on the mechanisms that determine floral volatile emission. In the present study, a total of 44 species/varieties of Chrysanthemum were analyzed to determine the relationship between the internal accumulation of floral terpenoids and their release as volatiles. By performing both headspace collection and organic extraction, it has been found that the emission rates of floral terpenoids are largely correlated to their internal concentrations. Particularly, the flowers of cultivated C. morifolium, when compared to their wild relatives, were found to exhibit lower emission rates that contain lowered concentrations of floral terpenoids. The differences were largely determined by six monoterpenes and five sesquiterpenes that were revealed by principal component analysis. Besides, the relationship between concentrations and emission rates of floral terpenoids as well as the sizes of capitulum was studied in detail. Separated into three different parts, disc florets were found to have a larger contribution to floral volatile emission than ray florets, whereas the phyllaries and receptacles are the main parts of volatiles accumulation. Finally, the potential biosynthetic pathway of the floral terpenoids produced in capitula of Chrysanthemum was proposed. In summary, our findings on the diversity and variations of floral terpenoids in Chrysanthemum reveal correlations between their production and emission. These findings can be useful to develop different plant breeding methods to create novel aromatic cultivars of Chrysanthemum.


Assuntos
Chrysanthemum/química , Odorantes/análise , Óleos Voláteis/química , Óleos Vegetais/química , Terpenos/química , Flores/química , Melhoramento Vegetal
13.
Int J Food Microbiol ; 351: 109262, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34090033

RESUMO

Chinese horse bean-chili-paste (CHCP), a fermented condiment in China, is traditionally manufactured through naturally spontaneous semi-solid fermentation procedures without intentionally inoculated microorganisms. The aim of this study was to investigate the effect on microbiota and quality variations during CHCP fermentation by inoculation of selected autochthonous microorganisms Bacillus amyloliquefaciens and Candida versatilis. The results showed that relative abundance of Bacillus in the samples inoculated with B. amyloliquefaciens were increased from about 0.6% to almost 25%, and the batches bio-augmented with C. versatilis exhibited clearly 0.7 Lg copies/g higher biomass than that of the other samples. By bio-augmentation, six enzyme activities, namely acid protease, leucine aminopeptidase, α-amylase, cellulose, ß-glucosidase and esterase, were considerably enhanced. As a result, inoculation of these two strains exhibited significant effect on the volatile profiles of CHCP. B. amyloliquefaciens herein was found to contribute mainly to the accumulation of acids, sulfur-containing compounds and pyrazines, whereas C. versatilis was considerably associated with the formation of alcohols, esters and phenols. This study proved that combination of B. amyloliquefaciens and C. versatilis could obtain more extensive aroma profiles, especially for the enrichment of miso-like and fruity flavors, which could provide a guideline for the tailored control of CHCP fermentation process.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Aromatizantes/metabolismo , Microbiota , Saccharomycetales/metabolismo , Vicia faba/microbiologia , China , Condimentos/análise , Condimentos/microbiologia , Fermentação , Aromatizantes/análise , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
14.
Molecules ; 26(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067274

RESUMO

The manufacture of counterfeit goods is one of the world's largest underground businesses and is rapidly growing. Counterfeits can lead not only to the loss of profit for honest producers but also have a negative impact on consumers who pay excessive prices for poor quality goods that may result in health or safety problems. The perfume industry is constantly vulnerable to counterfeits, particularly in the fast developing market of "smell-alike" designer-inspired perfumes because these prompt the identification of the methods that classify their quality. In this paper, the application of proton nuclear magnetic resonance (1H NMR) spectroscopy is employed for the first time to authenticate perfumery products. The molecular composition of several types of authentic brand fragrances for women was compared with cheap inspired equivalents and fakes. Our approach offers the prospect of a fast and simple method for detecting counterfeit perfumes using 1H NMR spectroscopy.


Assuntos
Técnicas de Química Analítica , Espectroscopia de Ressonância Magnética/métodos , Odorantes/análise , Perfumes/análise , Cromatografia Gasosa , Cromatografia Líquida , Cosméticos/análise , Reprodutibilidade dos Testes , Solventes
15.
Molecules ; 26(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065280

RESUMO

Yongchuan douchi is a traditional fermented soya bean product which is popular in Chinese dishes due to its unique flavor. In this study, the key aroma-active compounds of Yongchuan douchi were characterized by the combined gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS) with sensory evaluation. In total, 49 aroma compounds were sniffed and identified, and 20 of them with high flavor dilution factors (FD) and odor activity values (OAVs) greater than one were screened by applied aroma extract dilution analysis (AEDA) and quantitated analysis. Finally, aroma recombination and omission experiments were performed and 10 aroma-active compounds were thought to have contributed significantly including 2,3-butanedione (butter, cheese), dimethyl trisulfide (garlic-like), acetic acid (pungent sour), acetylpyrazine (popcorn-like), 3-methylvaleric acid (sweaty), 4-methylvaleric acid (sweaty), 2-mehoxyphenol (smoky), maltol (caramel), γ-nonanolactone (coconut-like), eugenol (woody) and phenylacetic acid (flora). In addition, sensory evaluation showed that the flavor profile of Yongchuan douchi mainly consisted of sauce-like, sour, nutty, smoky, caramel and fruity notes.


Assuntos
Alimentos e Bebidas Fermentados , Odorantes/análise , Soja/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Olfatometria/métodos
16.
Food Chem ; 361: 130029, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077885

RESUMO

A novel automated method was developed for the quantitative determination of nine terpenoids that could contribute to the minty notes of red wine bouquet. The method couples headspace SPME-Arrow extraction with GC-MS/MS analysis. PDMS/DVB fiber was chosen for the extraction and an ionization energy of 30 eV permitted to optimize the analyte detection. The optimal sample preparation consists of a two-fold dilution of the wine sample with addition of 4 g of sodium chloride while the most suitable extraction conditions take place at 50 °C for 1 h. The method shows good linearity, intraday variations between 2 and 25%, interday variations between 7 and 23% and recoveries between 80 and 119%. The method exhibits the required low detection (between 3 and 60 ng/L) and quantification (between 6 ng/L and 200 ng/L) limits. These limits have permitted the quantification of the pool of minty terpenoids in fourteen red Bordeaux wines.


Assuntos
Odorantes/análise , Microextração em Fase Sólida/métodos , Terpenos/isolamento & purificação , Vinho/análise , Monoterpenos Cicloexânicos/análise , Monoterpenos Cicloexânicos/isolamento & purificação , Dimetilpolisiloxanos , Eucaliptol/análise , Eucaliptol/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lactonas/análise , Lactonas/isolamento & purificação , Limoneno/análise , Limoneno/isolamento & purificação , Mentha , Mentol/análise , Mentol/isolamento & purificação , Polivinil , Espectrometria de Massas em Tandem/métodos , Terpenos/análise
17.
J Pharm Biomed Anal ; 203: 114180, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34111731

RESUMO

A headspace method called full evaporation technique (FET) coupled to capillary gas chromatography with a mass detector operating in time-of-flight mode (HS-GC/MS-TOF) was developed to characterize the volatile components, especially the terpene fraction, in Cannabis sativa L. inflorescences. This analytical approach allows to reach a high equilibration temperature, that was able to obtain a complete quantification of the volatile components, providing simple sample preparation, specific qualitative detection, high sensitivity, a precise and accurate quantitative determination. The method was applied to 20 cannabis THC-dominant (I) and 13 CBD-dominant (III) chemotypes. The obtained results were then compared with a series of standard solutions consisting of 35 terpenoids and the mass spectra present in a computer library (NIST). The method has an accuracy of more than 90 % and a limit of detection of 5 ppm for all analytes. The main terpenoids in cannabis are namely (% Chemotypes III vs. I of the total terpene content): ß-Caryophyllene (25 vs. 19.3), ß-Mircene (18.2 vs. 20.0), Terpinolene (12.1 vs. 7.0), α-Humulene (6.5 vs. 8.5), D-Limonene (6.2 vs. 7.2), α-Pinene (5.8 vs. 4.9), ß-Pinene (5.0 vs. 5.8) and cis-ß-Ocimene (4.3 vs. 5.2), whose presence is confirmed in both plant chemotypes and account for more than 80 % of the total terpenoids amount. The terpenoids which can clearly distinguish the chemotype are α-Terpineol, Linalool, DL-Menthol, α-Cedrene, and Borneol. This application provides important data on the secondary volatile components of the plant, which may be useful for a better understanding of the therapeutic properties of the cannabis phyto-complex. It gives the possibility of establishing the aroma profile of different Cannabis batches, allowing possible similarities between samples and identifying any artificial adulteration such as hexyl butyrate ester and it provides the opportunity to highlight some target compounds characteristic of the different chemotypes.


Assuntos
Cannabis , Alucinógenos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Terpenos/análise
18.
J Food Sci ; 86(7): 3228-3239, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34160060

RESUMO

Few studies have linked sensory descriptions of the aroma profiles of fresh, sweet basil varieties with their volatile chemistry. Using a recently developed lexicon for fresh basil, a descriptive panel characterized the aroma profiles of seven basil varieties. Chemical analysis of fresh basil leaves was performed using GC-MS headspace analysis. Analysis of variance probed for differences in the sensory attributes among varieties and principal component analysis (PCA) related the sensory profiles to volatile chemical composition. Three commercial specialty basils, "Queenette Thai" (QT), "Sweet-Dani" (SD) lemon basil, and MC-9 (cinnamon basil) had strong anise, lemon, and cinnamon-like aromas, respectively. These basils were distinguished from breeding lines of traditional Italian sweet basils where SB-22, CB-1, and CB-39 exhibited strong anise-like aroma and SB-17 had strong "general spice" aromas, characteristic of a warm spice blend. The PCA accounted for 58.7% of the variation in the data and characterized the samples in two dimensions: general spice-citrus and cinnamon-like-anise. There was a strong correspondence between the sensory attributes and volatile chemical composition. SD associated with lemon aroma and citral content; QT, CB-1, and CB-39 associated with anise aroma and methyl chavicol; and MC-9 associated with the cinnamon-like aroma, methyl cinnamate. SB-17 and SB-22 associated with general spice aroma and were in close proximity to the spice-like volatiles, 1,8 cineole, and eugenol, associated with clove aroma. We constructed precise sensory/chemical profiles for fresh basil aroma that can be used to guide breeding programs for variety improvement to meet consumer expectations or market demand. PRACTICAL APPLICATION: Sweet basil aroma is due to a complex array of several aromatic volatile compounds. The presence, concentration, and the particular ratios in which these aroma compounds accumulate significantly impact the sensory attributes. Understanding aroma profiles for fresh basil have practical applications in product development, procurement, food preparation, ethnic cuisine, and processing. Plant genetics and breeding of aroma profiles can be used and incorporated in plant improvement programs.


Assuntos
Ocimum basilicum/metabolismo , Odorantes/análise , Folhas de Planta/metabolismo , Compostos Orgânicos Voláteis/análise , Ocimum basilicum/química , Folhas de Planta/química
19.
Methods Mol Biol ; 2268: 85-95, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34085263

RESUMO

Mammalian olfactory receptors (ORs) constitute the largest family of G-protein-coupled receptors, with up to about 1000 different genes per species, each having specific odorant ligands. ORs could be used as sensing elements of highly specific and sensitive bioelectronic hybrid devices such as bioelectronic noses. After optimized immobilization onto the device, natural ORs provide molecular recognition of various odors with their intrinsic sensitivity, discrimination, and detection properties. However, the main difficulties are related to the low expression level of recombinant ORs, their stability and potential loss of activity. Such drawbacks can be successfully overcome in bioelectronic noses integrating nanosomes (nanometric membrane vesicles carrying ORs) that are stably immobilized through a specific antibody. The advantages of such a platform rely on the fact that ORs stay in the natural membrane environment, and thus preserve their full activity. Thanks to their small sizes, nanosomes offer potential for micro- and nano-scale sensor development. In this paper, we summarize the key elements regarding nanosomes production and manipulation and provide an example of their immobilization onto a gold sensor surface. Rat ORI7 is used as a representative OR that can be functionally expressed in Saccharomyces cerevisiae. The receptor was not purified but only nanosomes were prepared. Nanosomes were immobilized onto functionalized gold surface using the anti-I7 antibody. Utilization of the antibody provides enrichment of ORI7 on the sensor surface but also uniform and appropriate orientation of the receptors. These features are crucial in optimization of bioelectronic nose' analytical performances.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Proteínas Imobilizadas/metabolismo , Proteínas de Membrana/metabolismo , Odorantes/análise , Receptores Odorantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Animais , Ratos , Receptores Odorantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética
20.
J Agric Food Chem ; 69(27): 7709-7724, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34189912

RESUMO

Wine made from grapes subjected to accelerated ripening, an increasingly frequent phenomenon occurring in many wine regions due to peaks of heat and water stress, displays higher alcohol levels and lacks balance with color and flavor compounds. Herein, the rate of sugar accumulation of grapes was manipulated by varying the crop load and irrigation regime and the development of secondary metabolites was monitored by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). A 3-week delay in ripening correlated to an increase in the concentration of some monoterpenes and norisoprenoids and a greater decrease of green aroma compounds. Delayed ripening had a positive impact on the phenolic composition of grapes, displaying higher contents of total anthocyanins, total phenolics, quercetin glycosides, and polymeric pigments. A map of the chemical composition of grapes close to harvest allowed discrimination of compounds mainly responsive to delayed ripening from those driven by crop load or irrigation.


Assuntos
Vitis , Vinho , Antocianinas/análise , Frutas/química , Odorantes/análise , Água , Vinho/análise
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