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1.
Pestic Biochem Physiol ; 173: 104777, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33771256

RESUMO

Ceratocystis fimbriata is the pathogen of black rot disease, which widely exists in sweet potato producing areas all over the world. The antifungal activity of volatile organic compounds (VOCs) released by Pseudomonas chlororaphis subsp. aureofaciens SPS-41 against C. fimbriata was reported in our previous study. In this study, we attempted to reveal the underlying antifungal mechanism of SPS-41 volatiles. Our results showed that the VOCs released by SPS-41 caused the morphological change of hyphae, destroyed the integrity of cell membrane, reduced the content of ergosterol, and induced massive accumulation of reactive oxygen species in C. fimbriata cells. Furthermore, SPS-41 fumigation decreased the mitochondrial membrane potential, acetyl-CoA and pyruvate content of C. fimbriata cells, as well as the mitochondrial dehydrogenases activity. In addition, the VOCs generated by SPS-41 reduced the intracellular ATP content and increased the extracellular ATP content of C. fimbriata. In summary, SPS-41 fumigation exerted its antifungal activity by inducing oxidative stress and mitochondrial dysfunction in C. fimbriata.


Assuntos
Ascomicetos , Compostos Orgânicos Voláteis , Antifúngicos/farmacologia , Mitocôndrias , Estresse Oxidativo , Doenças das Plantas , Pseudomonas , Compostos Orgânicos Voláteis/farmacologia
2.
Food Chem ; 351: 129297, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33647692

RESUMO

Green glass (GG), ultraviolet grade absorbing glass (UVAGG), and multilayer (plastic-coated paperboard aluminium foil) (MLP) packagings were used for storing two commercially extra virgin olive oils (EVOOs) with different phenolic and volatile compound contents to evaluate their effect on oil quality evolution over 10 months of light exposure. Quality parameters such as free acidity, peroxide value, spectrophotometric indices, antioxidant and volatile compositions as well as sensory characteristics were evaluated; packaging material type and initial antioxidant composition significantly influenced EVOOs' resistance to oxidation, and consequently their quality. Compared with GG or UVAGG, MLP provided superior protection against oxidation; oils stored in MLP containers retained their characteristics within the regulatory limits and contained more antioxidants and fewer 'rancid' defect and related volatile compounds.


Assuntos
Armazenamento de Alimentos , Luz/efeitos adversos , Azeite de Oliva/análise , Polifenóis/análise , Compostos Orgânicos Voláteis/análise , Antioxidantes/análise , Oxirredução , Tempo
3.
Food Chem ; 351: 129308, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33652297

RESUMO

This study investigated the effects of foliar application of fulvic acid antitranspirant (FA-AT) on Cabernet Sauvignon (CS) and Riesling grapes and wines in a warm viticulture region of China. FA-AT controlled the contents of total soluble solids, fructose and glucose in mature grapes and alcohol in wines. FA-AT improved total phenols and flavonoids in Riesling grapes, and total tannin and individual flavanols in CS grapes and wine, while reducing total individual phenolic acids and flavonols in CS wine. Increased volatiles in CS grapes (hexyl acetate, linalool) and wine (isoamyl alcohol, 1-hexanol, 2-phenylethanol) detected by SPME-GC-MS can contribute to the fruity and floral aroma. FA-AT reduced the accumulation of anthocyanins in CS grapes and wine without an eventual reduction in the tonality of wine by sensory analysis, and improved the taste and balance of Riesling wine. Overall, FA-AT can improve the quality of grapes and wines produced in warm viticulture regions.


Assuntos
Agricultura/métodos , Benzopiranos/química , Frutas/química , Açúcares/análise , Vitis/química , Vinho/análise , Antocianinas/análise , China , Flavonoides/análise , Flavonóis/análise , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Fenóis/análise , Taninos/análise , Compostos Orgânicos Voláteis/análise
4.
Food Chem ; 352: 129380, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33667923

RESUMO

Solid-phase microextraction coupled to gas chromatography-mass spectrometry is a common approach to analyze the volatile profile of cooked meat. The present study aims to investigate the combined effect of sample preparation, including meat presentation (minced and steak) and cooking method (stewed and grilled), and extraction temperature (30, 60 and 80 °C) and time (30 and 50 min) on the volatile composition of cooked deer meat. The statistical results indicated that extraction temperature was the most relevant factor affecting the meat volatile profile of cooked meat followed by the extraction time. Higher extraction temperatures improved the detection of heavy volatile compounds, while sample preparation had little influence on the meat volatile profile, probably due to the accurate control of the parameters used for meat presentation and cooking methods. The results of this work can assist in the standardization of analytical procedures for the characterization of volatile compounds in cooked meat.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Culinária , Cromatografia Gasosa-Espectrometria de Massas , Carne/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Animais , Análise de Alimentos , Temperatura Alta , Compostos Orgânicos Voláteis/química
5.
Huan Jing Ke Xue ; 42(4): 1820-1829, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742817

RESUMO

This study aimed to investigate the pollution characteristics of the volatile organic compounds in Nansi Lake and evaluate the ecological and health risks. In November 2017, water samples collected from 25 sampling points in Nansi Lake using the purge and trap technique and GC-MS detected 52 types of VOCs. The detection rate of ethylbenzene, m-/p-xylene, o-xylene, 1,2-dichlorobenzene, and naphthalene reached 100%, and cis-1,3-dichloropropene and toluene reached 96%. The detection rate of 1,2,4-trimethyl benzene was the lowest, at only 12%, the average concentration of 1,2-dichlorobenzene was the highest, reaching 3.49 µg·L-1, and 1,2,4-trimethyl benzene was only 0.02 µg·L-1. The concentration of 1,2-dichlorobenzene in Nansi Lake was generally higher than that of other VOCs. Meanwhile, the concentrations of m-/p-xylene and ethylbenzene at point NSH-24 far exceeded the other VOCs, but the median value of all VOCs did not exceed 4 µg·L-1. The spatial distribution of the VOCs concentrations in Nansi Lake presented high values in the northwest and southeast, and low in the middle. The leading cause of VOCs pollution in Nansi Lake may be the exhaust gas emitted by shipping vessels during navigation, and the secondary cause is the collection of VOCs in the upstream and downstream tributaries and the influence of human factors. The health risk assessment of Nansi Lake found that, overall, there was no carcinogenic or non-carcinogenic health risk, but the risk value of individual points was relatively high, even exceeding the risk threshold set by the US EPA. There were 12 points in Nansi Lake where the ecological risk quotient exceeded 1, indicating an ecological risk to aquatic organisms.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Químicos da Água , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Humanos , Lagos , Medição de Risco , Compostos Orgânicos Voláteis/análise , Poluentes Químicos da Água/análise
6.
Molecules ; 26(4)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672299

RESUMO

This study presents the effect of the application of high-power ultrasound to crushed grapes, at a winery-scale, on the content of varietal volatile compounds (free and glycosidically-bound) in musts and on the overall aroma of wines. Two different frequencies (20 kHz and 28 kHz) were tested and the combination of grape sonication and different maceration times on wine aroma was also evaluated. The volatile compounds were isolated by solid phase extraction and analyzed by gas chromatography-mass spectrometry, carrying out a sensory evaluation of wines by quantitative descriptive analysis. Sonication produced an increase in the concentration of free varietal compounds such as C6 alcohols, terpenes and norisoprenoids in musts and also in wines made by 48 h of skin maceration, being less efficient in the extraction of the bound fraction. Fermentation compounds were also positively affected by ultrasound treatment, although this effect was variable depending on the frequency used, the maceration time and the type of compound. All the wines made from sonicated grapes had better scores in the evaluated olfactory attributes with respect to the control wines. Our results indicate that sonication could produce an increase in the content of some volatile compounds of sensory relevance, obtaining wines with an aroma quality similar or higher than those elaborated with longer maceration times.


Assuntos
Glicosídeos/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeos/metabolismo , Ondas Ultrassônicas , Compostos Orgânicos Voláteis/metabolismo
7.
Food Chem ; 352: 129363, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676120

RESUMO

A study was carried out to determine systematically the key aroma-active compounds of Langyatai Baijiu with Jian flavour (LBJF) using sensory omics analysis (SOA). A total of 56 odorants were screened out using gas chromatography-olfactometry-mass spectrometry (GC-O-MS)/Osme analysis. Among them, 15 aroma-active components were first identified. After quantitation, 30 odorants had odour activity values (OAVs) > 1.0 in LBJF. Recombinant and omission experiments proved that the esters, alcohols, acids, especially ethyl hexanoate, γ-nonalactone, and dimethyl trisulfide, were critical to the flavour of LBJF. The basic and commercial liquors had obvious differences in the skeleton compositions of esters and acids. This study uncovers the characteristics of Jian flavour Baijiu (JFB) and provides a scientific basis for the quality control of JFB, which is helpful for the development of Chinese Baijiu flavour styles.


Assuntos
Bebidas Alcoólicas/análise , Análise de Alimentos/métodos , Odorantes/análise , Paladar , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olfatometria , Compostos Orgânicos Voláteis/análise
8.
Food Chem ; 352: 129402, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690074

RESUMO

A non-thermal processing method was developed to promote preservation of brown rice using dielectric barrier discharge cold plasma (DBD-CP). Physicochemical properties including free fatty acid (FFA) content, surface color change, volatile organic components (VOCs) and flavor fingerprints were evaluated in brown rice submitted to DBD-CP. FFA levels were 25.2% lower in treated samples compared to the control, and a more stable surface color was obtained at the end of the storage period. A total of 35 major VOCs could be detected in treated samples, and reduced levels of hexanal can be used as an indicator of DBD-CP treatment in brown rice during storage. Moreover, the flavor fingerprints in DBD-CP treated groups can be successfully distinguished through headspace gas chromatography ion mobility spectrometry. Collectively, application of DBD-CP treatment could be utilized as a feasible approach to promote stabilization of brown rice and preserve flavor during storage.


Assuntos
Temperatura Baixa , Oryza/química , Gases em Plasma/química , Paladar , Impedância Elétrica , Compostos Orgânicos Voláteis/análise
9.
Molecules ; 26(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669237

RESUMO

Yeast plays a key role in the production of fermented foods and beverages, such as bread, wine, and other alcoholic beverages. They are able to produce and release from the fermentation environment large numbers of volatile organic compounds (VOCs). This is the reason for the great interest in the possibility of adapting these microorganisms to fermentation at reduced temperatures. By doing this, it would be possible to obtain better sensory profiles of the final products. It can reduce the addition of artificial flavors and enhancements to food products and influence other important factors of fermented food production. Here, we reviewed the genetic and physiological mechanisms by which yeasts adapt to low temperatures. Next, we discussed the importance of VOCs for the food industry, their biosynthesis, and the most common volatiles in fermented foods and described the beneficial impact of decreased temperature as a factor that contributes to improving the composition of the sensory profiles of fermented foods.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Meio Ambiente , Fermentação , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Adaptação Fisiológica/genética , Fermentação/genética , Saccharomyces cerevisiae/genética
10.
Molecules ; 26(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668517

RESUMO

Insect plagues are a problem often hard to solve due to the harmful effects caused by the pesticides used to combat them. Consequently, the pesticide market is increasingly trying to develop new technologies to prevent the unwanted effects that common plague treatments usually bring with them. In this work, four specific bioattractants of Musca domestica, extracted from fungi (ß-ocimene, phenol, p-cresol, and indole) were microencapsulated with ß-cyclodextrin in order to produce an economically and environmentally sustainable bait containing biocides in the near future. Cyclodextrins will retain these volatile compounds until their use by the consumer when the product comes into contact with water. Then, the bioattractants will be released in the medium in a controlled manner. An analytical methodology based on headspace extraction coupled to gas chromatography and mass spectrometry (HS-GC/MS) has been developed and validated following Environmental Protection Agency (EPA) and European Commission Directorate General for Health and Food Safety guidelines for the bioattractants controlled release study from the microencapsulated product. The analytical method has been shown to be accurate and precise and has the sensitivity required for controlled release studies of the four bioattractants analyzed. The release of the bioattractants from microencapsulated products achieved the "plateau" after 3 h in all cases.


Assuntos
Composição de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/toxicidade , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Praguicidas/química , Reprodutibilidade dos Testes , Compostos Orgânicos Voláteis/análise , Água/química
11.
Food Chem ; 352: 129450, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33714803

RESUMO

The unique flavor of and rich physiological activities exhibited by the Chinese JingJiu has made it become an essential part of the blended alcoholic beverage. In this study, the aromatic characteristics of Chinese JingJiu have been identified using sensory analysis, aroma extraction dilution analysis (AEDA), and quantitative analysis techniques. The odor activity values (OAVs) were also used to characterize the compound. A total of 136 aroma compounds were identified through the AEDA and gas chromatography-mass spectrometry (GC-MS) techniques. The flavor dilution (FD) factors were found to be in the range of 2-1024. Seventy aroma-active compounds with FD ≥ 8 were identified. Forty-three aroma-active compounds were identified using the molecular sensory science approach. Furthermore, 13 compounds were confirmed to be the key aroma-active compounds present in the Chinese JingJiu. The work provides a certain guiding effect on the regulation and optimization of the Chinese JingJiu production process.


Assuntos
Bebidas Alcoólicas/análise , Análise de Alimentos/métodos , Odorantes/análise , Cromatografia Gasosa-Espectrometria de Massas , Técnicas de Diluição do Indicador , Paladar , Compostos Orgânicos Voláteis/análise
12.
Molecules ; 26(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672898

RESUMO

The research concerns the use of proton transfer reaction mass spectrometer to track real-time emissions of volatile secondary oxidation products released from rapeseed oil as a result of deep-frying of potato cubes. Therefore, it was possible to observe a sudden increase of volatile organic compound (VOC) emissions caused by immersion of the food, accompanied by a sudden release of steam from a potato cube and a decrease of the oil temperature by more than 20 °C. It was possible to identify and monitor the emission of major secondary oxidation products such as saturated and unsaturated aldehydes, namely acrolein, pentanal, 2-hexenal, hexanal, 2-nonenal and 2-decenal. Each of them has an individual release characteristic. Moreover, the impact of different initial frying temperatures on release kinetics was investigated. Subsequently, it was possible to approximate the cumulative emission by a second-degree polynomial (R2 ≥ 0.994). Using the proposed solution made it possible for the first time to observe the impact of the immersion of food in vegetable oil on the early emission of thermal degradation products oil.


Assuntos
Culinária , Óleo de Brassica napus/química , Compostos Orgânicos Voláteis/análise , Cinética , Oxirredução , Solanum tuberosum/química , Temperatura
13.
Molecules ; 26(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672961

RESUMO

Miscanthus is resistant to dry, frosty winters in Poland and most European Union countries. Miscanthus gives higher yields compared to native species. Farmers can produce Miscanthus pellets after drying it for their own heating purposes. From the third year, the most efficient plant development begins, resulting in a yield of 25-30 tons of dry matter from an area of 1 hectare. Laboratory scale tests were carried out on the processes of drying, compacting, and torrefaction of this biomass type. The analysis of the drying process was conducted at three temperature levels of the drying agent (60, 100, and 140 °C). Compaction on a hydraulic press was carried out in the pressure range characteristic of a pressure agglomeration (130.8-457.8 MPa) at different moisture contents of the raw material (0.5% and 10%). The main interest in this part was to assess the influence of drying temperature, moisture content, and compaction pressure on the specific densities (DE) and the mechanical durability of the pellets (DU). In the next step, laboratory analyses of the torrefaction process were carried out, initially using the Thermogravimetric Analysis TGA and Differential Scaning Calorimeter DSC techniques (to assess activation energy (EA)), followed by a flow reactor operating at five temperature levels (225, 250, 275, 300, and 525 °C). A SEM analysis of Miscanthus after torrefaction processes at three different temperatures was performed. Both the parameters of biochar (proximate and ultimate analysis) and the quality of the torgas (volatile organic content (VOC)) were analyzed. The results show that both drying temperature and moisture level will affect the quality of the pellets. Analysis of the torrefaction process shows clearly that the optimum process temperature would be around 300-340 °C from a mass loss ratio and economical perspective.


Assuntos
Biocombustíveis , Dessecação , Fertilizantes , Poaceae/química , Temperatura , Análise de Variância , Biomassa , Varredura Diferencial de Calorimetria , Cinética , Tamanho da Partícula , Poaceae/ultraestrutura , Termogravimetria , Fatores de Tempo , Compostos Orgânicos Voláteis/análise , Volatilização
14.
J Environ Sci (China) ; 103: 135-147, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743896

RESUMO

Trace analysis of volatile organic compounds (VOCs) during wildfires is imperative for environmental and health risk assessment. The use of gas sampling devices mounted on unmanned aerial vehicles (UAVs) to chemically sample air during wildfires is of great interest because these devices move freely about their environment, allowing for more representative air samples and the ability to sample areas dangerous or unreachable by humans. This work presents chemical data from air samples obtained in Davis, CA during the most destructive wildfire in California's history - the 2018 Camp Fire - as well as the deployment of our sampling device during a controlled experimental fire while fixed to a UAV. The sampling mechanism was an in-house manufactured micro-gas preconcentrator (µPC) embedded onto a compact battery-operated sampler that was returned to the laboratory for chemical analysis. Compounds commonly observed in wildfires were detected during the Camp Fire using gas chromatography mass spectrometry (GC-MS), including BTEX (benzene, toluene, ethylbenzene, m+p-xylene, and o-xylene), benzaldehyde, 1,4-dichlorobenzene, naphthalene, 1,2,3-trimethylbenzene and 1-ethyl-3-methylbenzene. Concentrations of BTEX were calculated and we observed that benzene and toluene were highest with average concentrations of 4.7 and 15.1 µg/m3, respectively. Numerous fire-related compounds including BTEX and aldehydes such as octanal and nonanal were detected upon experimental fire ignition, even at a much smaller sampling time compared to samples taken during the Camp Fire. Analysis of the air samples taken both stationary during the Camp Fire and mobile during an experimental fire show the successful operation of our sampler in a fire environment.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Benzeno , California , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Tolueno/análise , Compostos Orgânicos Voláteis/análise , Xilenos
15.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33649215

RESUMO

Surface ozone is a severe air pollution problem in the North China Plain, which is home to 300 million people. Ozone concentrations are highest in summer, driven by fast photochemical production of hydrogen oxide radicals (HOx) that can overcome the radical titration caused by high emissions of nitrogen oxides (NOx) from fuel combustion. Ozone has been very low during winter haze (particulate) pollution episodes. However, the abrupt decrease of NOx emissions following the COVID-19 lockdown in January 2020 reveals a switch to fast ozone production during winter haze episodes with maximum daily 8-h average (MDA8) ozone concentrations of 60 to 70 parts per billion. We reproduce this switch with the GEOS-Chem model, where the fast production of ozone is driven by HOx radicals from photolysis of formaldehyde, overcoming radical titration from the decreased NOx emissions. Formaldehyde is produced by oxidation of reactive volatile organic compounds (VOCs), which have very high emissions in the North China Plain. This remarkable switch to an ozone-producing regime in January-February following the lockdown illustrates a more general tendency from 2013 to 2019 of increasing winter-spring ozone in the North China Plain and increasing association of high ozone with winter haze events, as pollution control efforts have targeted NOx emissions (30% decrease) while VOC emissions have remained constant. Decreasing VOC emissions would avoid further spreading of severe ozone pollution events into the winter-spring season.


Assuntos
Poluição do Ar/análise , Ozônio/análise , Material Particulado/análise , Estações do Ano , Compostos Orgânicos Voláteis , China , Produtos Agrícolas , Monitoramento Ambiental , Poluição Ambiental , Humanos , Óxidos de Nitrogênio/química , Pandemias , Saúde Pública
16.
J Environ Manage ; 286: 112202, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33618319

RESUMO

The degradation of four recalcitrant and toxic VOCs (volatile organic compounds) present in pharmaceutical wastewater was studied using a continuous flow plasma reactor, along with evaluating its potential for real effluent treatment. The wastewater was sprayed into the plasma zone of the reactor, and it was re-circulated for better performance. The effect of different HRTs (hydraulic retention time) and initial concentrations of VOCs on the degradation efficiency were evaluated. In continuous reactor, complete removal of 200 mg/L of chloroform, chlorobenzene, and toluene was achieved at a HRT of 33.3 min, with an energy consumption of 22.4 kWh/m3. The study on the effect of different inlet loading rates of VOCs on elimination capacity showed that, the removal was limited initially by diffusion of reactive species and at higher loads, it was limited by insufficient amount of reactive species produced. During degradation of VOC mixture, more than 90% removal of chloroform, chlorobenzene and toluene was achieved at HRT of 33.3 min, and the TOC removal was 78.3%. The degradation efficiency of VOC mixture reduced slightly compared to that of individual compounds, due to insufficient amount of reactive species produced. The COD and BOD removal achieved after 140 min of direct plasma treatment of real pharmaceutical wastewater in batch reactor was 92.7% and 95.2%, respectively. Coagulation pre-treatment did not have a significant effect on the plasma treatment of real wastewater. When pharmaceutical effluent treatment was carried out in continuous flow reactor, 91.8% COD removal, 90.9% BOD removal and more than 90% degradation of all VOCs were achieved at a HRT of 150 min. Plasma treatment alone was capable of effectively treating the real pharmaceutical wastewater without any pre-treatment.


Assuntos
Preparações Farmacêuticas , Compostos Orgânicos Voláteis , Reatores Biológicos , Plasma , Eliminação de Resíduos Líquidos , Águas Residuárias
17.
Int J Food Microbiol ; 342: 109092, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33607541

RESUMO

Tomato is widely consumed and marketed as juice, puree, or fresh product. Nevertheless, 30% of its harvest volume is lost because of the fungus Alternaria alternata. This research aimed to provide early detection methods for this fungal decay on tomato juice and fresh fruit. Biomass content, CO2, O2 and volatile compounds (VOCs) during A. alternata growth in tomato juice and fruit at two ripening stages (breaker and red colour) were evaluated. Additionally, CO2 and VOCs data set were analysed with a hierarchical cluster technique (HCA) to explore the differences between inoculated and non-inoculated samples. Biomass was determined by gravimetry, CO2 and O2 by gas chromatography (GC), and VOCs by GC-mass spectrometry. Biomass content was not drastically modified by tomato's ripening stage (3-6 mg of dry weight). CO2 in tomato juice was considerably higher in the inoculated samples with A. alternata (27-63%) than in the non-inoculated ones (2.8-6.6%), regardless of the ripeness stage; while in tomato fruit CO2 was higher at breaker stage and inoculated with A. alternata (33-41%) than the remaining treatments (9-23%). It was also observed that, except for limonene, trans-sabinene hydrate, and rhodovibrin, VOCs' release during the interaction between tomato juice and A. alternata was different from the fresh tomato and A. alternata interaction. Only the HCA based on CO2 data showed clear differences between the inoculated and non-inoculated tomato juice and fruit at both ripening stages.


Assuntos
Alternaria/isolamento & purificação , Sucos de Frutas e Vegetais/microbiologia , Frutas/microbiologia , Lycopersicon esculentum/microbiologia , Alternaria/metabolismo , Biomassa , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Microbiologia de Alimentos , Frutas/química , Sucos de Frutas e Vegetais/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
18.
Sci Total Environ ; 773: 145453, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582357

RESUMO

Due to the large amount, environmental impact, and complex properties of accumulated food waste, its disposal and valorization has become a growing global concern and challenges. In this study, a series of mesopore-enriched hierarchical porous carbons were synthesized from a mixture of two food waste components (peptone and bone). The prepared materials were employed for the rapid adsorption of aromatic volatile organic compounds (VOCs). The pore structures, morphology and surface chemistry of the food waste-based microporous activated carbon (PCs) and mesopore-enriched hierarchical porous carbons (PC/BCs) were characterized and then compared. PC/BCs presented larger pore volume (2.45 cm3/g vs. 1.25 cm3/g) than the PCs because of their activation and the template effect of the bone, allowing them to exhibit satisfactory adsorption capacities (139.5 mg/g for benzene and 440.7 mg/g for toluene) and adsorption rate (0.285 min-1 for benzene and 0.236 min-1 for toluene) for aromatic VOCs. In addition, a strong linear relationship (R2 = 0.957) was also established between the adsorption rate k and total pore volume, highlighting the role of mesopores in PC/BCs, which contributed 60% to the total pore volume, during the rapid capture of VOCs. Further, PC/BCs also showed excellent thermal regeneration performance for more than four runs. The results of this study provide a feasible approach to fabricating mesopore-enriched hierarchical porous carbon from food waste, which could enable the rapid removal of VOCs.


Assuntos
Eliminação de Resíduos , Compostos Orgânicos Voláteis , Adsorção , Alimentos , Porosidade
19.
Food Chem ; 349: 129173, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582543

RESUMO

Change in metabolites and volatiles during yellowing process in six rice cultivars was analyzed. Based on the yellowness, the study indicated Japonica was more prone to yellowing than Indica rice. Metabonomics analysis showed most differential metabolites were up-regulated, in which pathways of flavone and flavonol biosynthesis were significantly enriched following the yellowing process. Meanwhile, 54 differential metabolites were overlapped in six comparative groups, which is characterized by commonly-shared metabolic regulation pathway in each rice. Phenylalanine content was increased, followed by the enhanced phenylpropanoids formation, showing transformation between primary and secondary metabolites during yellowing process. Furthermore, 43 volatile compounds were identified, and the yellowed rice had more volatiles, including ketones, alcohols, esters and hydrocarbons, suggesting a positive correlation with the yellowing. Compounds 6-methyl-5-hepten-2-one and 6,10,14-trimethyl-2-pentadecanone were increased steadily during yellowing process, which may be applied for monitoring rice yellowing progress. This investigation provides further insight for revealing rice yellowing mechanism.


Assuntos
Metabolômica , Oryza/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Cor , Oryza/classificação , Metabolismo Secundário , Especificidade da Espécie
20.
Food Chem ; 349: 129216, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581436

RESUMO

The objective of the study was to investigate the effect of mechanical vibration on postharvest quality and volatile compounds in blueberries (Vaccinium spp. Berkeley). Ethylene production, respiratory rate, firmness, decay incidence, soluble solids content (SSC), titratable acid content (TAC), flavonoid content, total phenols content (TPC), enzyme activity and volatile compounds of blueberry fruit were determined. Results showed that mechanical vibration resulted in the increase of ethylene production, respiratory rate, decay incidence and the decrease of firmness, enzyme activity, SSC, TAC, flavonoid content, TPC in blueberries comparing with the control. Moreover, mechanical vibration improved the relative content of alcohols and decreased the relative content of esters in comparison with the control group. In conclusion, the effect of transport vibration on blueberry quality was conspicuous. The quality of blueberry fruit gradually decreased with the extension of vibration time during the transportation, which seriously reduced storage life and commodity value of blueberries.


Assuntos
Mirtilos Azuis (Planta)/química , Qualidade dos Alimentos , Frutas/química , Vibração , Compostos Orgânicos Voláteis/análise
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