Total Aldehydes Research Articles

An air emission risk assessment of non-criteria pollutants in a tunnel study in Rio de Janeiro, Brazil.

Brazil's significantly large fleet of ethanol-powered vehicles makes it unique with regard to mobile source emissions. An accurate estimation of emission rates is best obtained from studies reflecting real-world vehicular conditions, such as tunnel investigations. Although laboratory-based estimations are standardized, they may not reflect reality. This study evaluates two methods for estimating emission factors that arise from the circulating fleet of vehicles that travel through the Rebouças Tunnel in Rio de Janeiro. The two monitoring points were located in the L1 gallery of the tunnel. Thirteen sampling campaigns took place between 2017 and 2020. The Pierson correlation method yielded emission rates for total aldehydes of 22.1 ± 6.9mgkm-1, while the fuel consumption testing method resulted in rates of 17.7 ± 7.8mgkm-1. Acetaldehyde predominated in both methods, as it is a major constituent of the exhaust emissions using ethanol as fuel, which is one of the major component fuels in the Brazilian fuel matrix. Benzene emerged as the most abundant BTEX compound, with 3.7 ± 3.2mgkm-1, when the Pierson method was used, and 2.5 ± 0.3mgkm-1 with the fuel consumption testing method. Naphthalene, which was mainly collected in the gas phase, showed rates of 1.4 ± 1.0mgkm-1 (Pierson) and 0.9 ± 0.4mgkm-1 (fuel consumption). Despite these methodological variations, our findings converge, which suggests that the choice of method should depend on available resources. The Pierson method, which requires a vehicle counting method for traffic flow, obviates the need for CO and CO2 concentration measurements, that are essential for determining fuel consumption.

Preharvest applications of monopotassium phosphate to improve fruit quality and volatilome composition in cold-stored cherry tomatoes

The experiment addressed the effects of preharvest KH2PO4 foliar spraying (20 mmol · L−1) on fruit quality and composition (including volatile organic compounds, VOCs) of cherry tomatoes (‘Caravaggio’, ‘Sugarland’ and ‘Top Stellina’) after 0 (S0), 7 (S7) and 14 days (S14) of storage at 8.0 °C. On the average of the 3 genotypes, the KH2PO4 treatment improved fruit pressure firmness, total soluble solids (TSS), titratable acidity (TA), total phenols and carotenoids concentrations, along with the fruits' antioxidant capacity (by up to 17% for FRAP assay). Within the S7–S14 period, control fruits showed the highest reductions in TSS, TSS/TA ratio and total carotenoids (−17, −12 and −45, respectively), whereas treated fruits proved the strongest increase in DPPH (+12%). Sixteen out of 32 VOCs were promoted following KH2PO4 application, including the aldehydes hexanal, (E)-2-hexenal and (Z)-3-hexenal and the apocarotenoids (E)-citral, (E)-β-ionone, geranylacetone and 6-methyl-5-hepten-2-one. Proceeding from S0 to S14, several VOCs decreased more strongly in control fruits, as for hexanal (−48%∖) and total aldehydes (−42%∖, whereas at S14 treated fruits had higher concentrations of linalool, geranylacetone and 6-methyl-5-hepten-2-one (1.06, 52.50 and 79.27 μg · kg−1, respectively). ‘Caravaggio’ demonstrated the strongest apocarotenoid reduction at S14, whereas ‘Top Stellina’ was more responsive to KH2PO4 (mainly for β-cyclocitral, geranylacetone and total terpenes/terpenoids), thus highlighting the central role of the genotype in responding to other experimental factors. Nonetheless, these results suggest that proper preharvest KH2PO4 applications can preserve specific commercial, nutritional and quality traits of cold-stored cherry tomatoes.

The revelation of characteristic volatile compounds in egg powder and analysis of their adsorption rules based on HS-GC-IMS technology

The study constructed fingerprints and analyzed adsorption rules of volatile compounds (VOCs) in egg powder (EP) under different production processes, including egg white powder (EWP), egg yolk powder (EYP) and whole egg powder (WEP) by HS-GC-IMS. The 29 VOCs identified were primarily ketones and aldehydes. Characteristic VOCs responsible for flavor differences were clarified by difference comparison, clustering and PCA analysis. Additionally, variations in lipid and protein were the primary causes of the VOCs differences in EP through microscopy imaging, infrared and fluorescence spectroscopy. EWP's stretched structure favored fishy-smelling VOCs adsorption but limited total aldehyde binding due to strong hydrophobic interaction. EYP's higher β-sheet ratio and fewer hydrogen bond sites weakened its alcohol VOCs binding capacity. The abundance of ketone VOCs in EP was linked to their low steric hindrance. Therefore, this study elucidated the flavor differences reasons among EWP, EYP and WEP, laying foundation for EP applications in food industry.

Highly sensitive analysis of fatty aldehydes in vegetable oils using a novel coumarin-based fluorescent probe by HPLC for quality control

A novel fluorescent probe, 3-(4-((hydroxylamino)methyl)-1H-pyrazol-1-yl)-7-methoxyl coumarin (HAPMC), has been designed and synthesized. The compound exhibits exceptional fluorescence properties due to a coumarin-pyrazolyl fluorophore. Moreover, it incorporates an N-hydroxylamine functional group capable of reacting with aldehydes to yield nitrone derivatives under mild conditions. This unique combination renders it an ideal derivatization reagent for aldehyde analysis. A standard method was established for the quantitative analysis of eight fatty aldehydes by utilizing high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and a pre-column derivatization process, which has low detection limits (0.3–1.2 nM), satisfactory reproducibility (intraday and interday relative standard deviations in the range of 1.29 %-2.92 % and 1.73 %-3.45 %), and an extensive linear range (25–5000 nM) with excellent linearity (R2 ≥ 0.9989). The spiked recoveries of the fatty aldehydes range from 89.6 % to 106.0 %. The greenness and sustainability of our approach are reinforced by evaluations conducted with the AGREE and RGB 12 algorithms. The established method was successfully applied to the qualitative and quantitative detection of fatty aldehydes in nine real vegetable oil samples, including peanut, canola, rice, soybean, olive, rapeseed, corn, sunflower, and blended oils. The fatty aldehydes are known to have adverse effects on human health due to their carcinogenic and mutagenic properties. The findings revealed that hexanal and nonanal were the most prevalent saturated fatty aldehydes, with a notable increase in the total aldehyde concentration observed as the temperature and duration of heating increased. Compared to alternative analytical techniques, this pre-column derivatization method utilizing HAPMC displayed simplicity, reliability, and sensitivity. The results demonstrate the potential for broad application of this approach in various important research domains, including food quality control, environmental monitoring, and medical research.

Influence of the thickness of oak alternatives on the composition and quality of red wines

This work studies the influence of the thickness of oak alternatives on the composition and quality of red wines. A red wine was aged in control conditions and also in contact with oak chips, and with thin and thick oak staves for 12 months. As expected, all the wines aged in contact with all the oak alternatives were enriched in total polyphenols and had a higher colour intensity. In addition, the contact with all the oak alternatives enriched the wine in furfural and total furans, vanilla and total aldehydes and ketones, eugenol and total volatile phenols, and in β-methyl-γ-octalactones. However, the thickness of the oak alternative seems to play an important role in the composition and quality of the wine. Specifically, the wines aged in contact with the two types of staves had a more intense colour than the wine aged with oak chips, as well as a higher total phenolic index and higher eugenol concentration. Moreover, the β-methyl-γ-octalactones concentration was higher in the wine supplemented with thick staves. Finally, the wines supplemented with the two types of staves had a higher intensity of the spicy attribute than the wine aged with oak chips. The wine supplemented with thick staves had a higher intensity of candy/pastry, toasted, smoked, complexity, aromatic intensity, sweetness, structure, and persistence. Finally, the panel preferred the wine aged with thick staves followed by, in descending order, the wines aged with thin staves, oak chips, and the control.

Tunable fluorescent probes for detecting aldehydes in living systems.

Aldehydes, pervasive in various environments, pose health risks at elevated levels due to their collective toxic effects via shared mechanisms. Monitoring total aldehyde content in living systems is crucial due to their cumulative impact. Current methods for detecting cellular aldehydes are limited to UV and visible ranges, restricting their analysis in living systems. This study introduces an innovative reaction-based trigger that leverages the exceptional selectivity of 2-aminothiophenol for aldehydes, leading to the production of dihydrobenzothiazole and activating a fluorescence response. Using this trigger, we developed a series of fluorescent probes for aldehydes by altering the fluorophore allowing for excitation and emission wavelengths across the visible to near-infrared spectral regions without compromising the reactivity of the bioorthogonal moiety. These probes exhibit remarkable aldehyde chemoselectivity, rapid kinetics, and high quantum yields, enabling the detection of diverse aldehyde types, both exogenous and endogenous, within complex biological contexts. Notably, we employed the most red-shifted near-infrared probe from this series to detect aldehydes in living systems, including biliary organoids and mouse organs. These probes provide valuable tools for exploring the multifaceted roles of aldehydes in biological functions and diseases within living systems, laying the groundwork for further investigations.

Effects of hydrolyzed animal protein application on nitrogen translocation, phenolic and volatile profile of Ocimum basilicum L. under salinity conditions

The application of biostimulants based on hydrolysed animal protein to leaves (foliar) or nutrient solution was studied on hydroponically grown Genovese 'Marian' basil grown under salinity conditions. The effect on N yield and N fertilizer utilization was tested with the stable isotope 15N, which indicated the part of the plant that accumulated the highest amount of N. The use of the biostimulant in the nutrient solution produced the best results regarding N fertilizer utilization and N yield, being about 13 % higher than the foliar application and 24 % higher than the salt control (SC) treatment. In general, basil leaves contained the most N from the fertilizer. The total analysed phenolic content (TAPC) was 270.1 % higher in the nutrient solution-applied biostimulant (NSB) than in the control (C) treatment and 211.9 % higher than in the SC treatment. Foliar application of the biostimulant (FB) showed lower efficacy than NSB regarding phenolic contents. The most abundant individual phenolics in basil were dihydroxyphenyllactic acid dimer, caffeic acid hexoside derivatives, and rosmarinic acid. NSB increased the total sesquiterpene content by 25.2 % and the total alcohol content by 31.8 % compared to SC treatment. In addition, NSB increased the total aldehydes content by 27.0 % compared to SC treatment. The total volatile content was less variable than the individual volatiles. The results of our study show how different application methods of the biostimulant affect nitrogen conversion and utilization in different plant parts of basil and how they influence the internal quality of basil.

Factors influencing the emissions of aldehydes from plant species of the Korean peninsula

This study present the factors controlling the aldehyde emission (formaldehyde, acetaldehyde, propionaldehyde, etc.) from plant species such as Pinus densiflora, Pinus koraiensis, Quercus acutissima, Quercus variabilis, Ginkgo biloba, and Oryza sativa. Even in the same tree species illustrate the emission rate variation of as much as 30 ~ 40%. The β-value, a parameter quantifying the temperature and emission correlation, were assessed as 0.07, 0.05 for formaldehyde and acetaldehyde, respectively. The coefficient of correlation was 0.4 and 0.5. for Quercus variabilis. In addition, the correlation between PAR (photosynthetically active radiation) and the emission is assessed close to the temperature impact on the emission. The emission of formaldehyde and acetaldehyde from P. densiflora, P. koraiensis, and Q. variabilis also depends on temperature and PAR. The ERs of total aldehydes of P. koraiensis are assessed at the level of 357.2 ng gdw−1 h−1, followed by propionaldehyde (110.6 ng gdw−1 h−1), acetaldehyde (102.5 ng gdw−1 h−1), and formaldehyde (73.66 ng gdw−1 h−1).

Effects of Stigmasterol on 3-Chloropropane-1,2-diol Fatty Acid Esters and Aldehydes Formation in Heated Soybean Oil.

In this study, we investigated the inhibitory effects of three soybean isoflavones and two soybean phytosterols on the formation of 3-chloropropane-1,2-diol fatty acid esters (3-MCPDE) and aldehydes in heated soybean oil model. 0.4 mM of genistin, genistein, daidzein, stigmasterol, and β-sitosterol significantly reduced 3-MCPDE formation by 25.7, 51.4, 21.4, 61.6, and 55.7%, and total aldehydes formation by 42.03, 43.94, 28.36, 54.74, and 39.23%, respectively. Further study showed that stigmasterol reduced the content of glycidyl esters (GEs) and glycidol, two key intermediates of 3-MCPDE, and prevented fatty acids degradation in the oils. Moreover, the effects of continuous frying time on the content of stigmasterol and the migration of stigmasterol were evaluated in the fried dough sticks model system. The content of stigmasterol in soybean oil was found to be significantly decreased with prolonged heating time. The concentrations of stigmasterol in fried dough sticks and the migration rates of stigmasterol from soybean oil to fried dough sticks decreased with repeated frying sessions. In addition, stigmasterol undergoes oxidative changes during heat treatment, and the oxidation products including 5,6α-epoxystigmasterol, 5,6β-epoxystigmasterol, 7α-hydroxystigmasterol, 7β-hydroxystigmasterol, stigmasterlol-3β,5α,6β-triol, and 7-ketostigmasterol were identified in the frying oils but not in the fried dough sticks. Overall, stigmasterol could be added to soybean oil to reduce 3-MCPDE and aldehydes formation, and reacting with GEs/glycidol and protection of lipid acids from oxidation may be the mechanism of action of stigmasterol.

One‐pot synthesis of V doped mesoporous SiO2 catalysts for selective oxidation of ethane and propane

AbstractA series of vanadium‐doped mesoporous SiO2 catalysts were prepared using a one‐pot emulsion method. The effects of VOx species with different structures on C−H bond activation and product selectivity in ethane and propane selective oxidation were investigated using X‐ray diffraction (XRD), N2 adsorption‐desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, ultraviolet‐visible diffuse reflectance spectroscopy (UV‐Vis DRS), hydrogen temperature programmed reduction (H2‐TPR), and ammonia temperature programmed desorption (NH3‐TPD) characterizations. The results revealed that the highly dispersed isolated tetrahedral VOx species on the catalyst gradually polymerized into highly dispersed oligomeric VOx species with the increased V loading. The former is beneficial for the formation of olefins and total aldehydes during the selective oxidation of propane. Oligomeric VOx species are conducive to improving the selectivity of ethylene and acetaldehyde in the selective oxidation of ethane. The highest catalytic performances for selective oxidation of ethane and propane were obtained at a temperature of 650 °C. The conversion of ethane was 41.6 %, with a corresponding yield of ethylene and acetaldehyde of 23.6 % over a 0.5 V−SiO2 catalyst. In contrast, the propane conversion was 61.5 %, with a corresponding total yield of olefins and aldehydes of 41.3 % over a 1.0 V−SiO2 catalyst.

Counteracting Roles of Lipidic Aldehydes and Phenolic Antioxidants on Soy Protein Oxidation Defined by a Chemometric Survey of Solvent and Mechanically Extracted Soybean Meals.

Soybean meal (SBM) is a premier source of protein for feeding food-producing animals. However, its nutritional value can be compromised by protein oxidation. In this study, a total of 54 sources of solvent extracted SBM (SSBM) and eight sources of mechanically extracted SBM (MSBM), collected from different commercial producers and geographic locations in the United States during the years 2020 and 2021, were examined by chemometric analysis to determine the extent of protein oxidation and its correlation with soybean oil extraction methods and non-protein components. The results showed substantial differences between SSBM and MSBM in the proximate analysis composition, protein carbonyl content, lipidic aldehydes, and antioxidants, as well as subtle differences between 2020 SSBM and 2021 SSBM samples in protein oxidation and moisture content. Correlation analysis further showed positive correlations between protein carbonyl content and multiple lipid parameters, including the ether extract, p-anisidine value, individual aldehydes, and total aldehydes. Among the antioxidants in SBM, negative correlations with protein carbonyl content were observed for total phenolic content and isoflavone glycoside concentrations, but not for Trolox equivalent antioxidant capacity (TEAC), α-tocopherol, and γ-tocopherol. Overall, soybean oil extraction methods, together with other factors such as enzyme treatment and environmental conditions, can significantly affect the proximate analysis composition, the protein and lipid oxidation status, and the antioxidant profile of SBM. Lipidic aldehydes and phenolic antioxidants play counteracting roles in the oxidation of soy protein. The range of protein carbonyl content measured in this study could serve as a reference to evaluate the protein quality of SBM from various sources used in animal feed.

Fermented mixed feed regulates intestinal microbial community and metabolism and alters pork flavor and umami

This study aimed to determine the effects of fermented mixed feed (FMF) supplementation (0%, 5% and 10%) on the intestinal microbial community and metabolism, and the compositions of volatile flavor compounds and inosine monophosphate (IMP) contents in the longissimus thoracis. In this study, 144 finishing pigs (Duroc × Berkshire × Jiaxing Black) were randomly allocated to 3 groups with 4 replicate pens per group and 12 pigs per pen. The experiment lasted 38 days after 4 days of acclimation. The 16S rRNA gene sequences and an untargeted metabolomics analysis showed FMF altered the profiles of microbes and metabolites in the colon. Heracles flash GC e-nose analysis showed that 10% FMF (treatment 3) had a greater influence on the compositions of volatile flavor compounds than 5% FMF (treatment 2). Compared to 0% FMF (treatment 1), the contents of total aldehydes, (E,E)-2,4-nonadienal, dodecanal, nonanal and 2-decenal were significantly increased by treatment 3, and treatment 3 increased IMP concentrations and gene expressions related to its synthesis. Correlations analysis showed significantly different microbes and metabolites had strong correlations with the contents of IMP and volatile flavor compounds. In conclusion, treatment 3 regulated intestinal microbial community and metabolism, that in turn altered the compositions of volatile compounds, which contributed to improving pork flavor and umami.

Spatiotemporal mapping of atmospheric aldehydes over Beijing in summer during 2019–2021 via their source apportionment study

Atmospheric aldehydes have the important impacts on human health and air pollutions, however, their surface concentrations are never captured due to the sparse monitoring works and need to be studied. Here, we tried to map the aldehyde pollutions over Beijing in summer of recent years, via monitoring their levels in one urban site, simulating their chemical formations based on box chemical model, and developing their prediction formulae by using CO and O3 as explanatory variables based on statistical technique. Our monitoring showed that HCHO and CH3CHO were the dominant components respectively at the level of 4.5–27.2 and 0.9–10.78 ppb, and explained 86.9% of total aldehydes detected. Their mixing ratios to CO were higher by a factor of 2.5–4.0 than the corresponding emission ratios from combustion sources, which implied a big contribution of photochemistry to secondary aldehyde formation. Hence, we used box model coupled with MCM to simulate the evolutions of HCHO, CH3CHO and O3 from the emission plumes of this city, and found the production ratio of 0.14 for HCHO:O3 and 0.07 for CH3CHO:O3 on daytime average. Afterwards, we developed the prediction formulae separately for the two aldehydes based on multiple linear regression by using CO and O3 as explanatory variables, and obtained the regression coefficients of ∼0.15 (HCHO) and ∼ 0.04 (CH3CHO) with O3, which were well consistent with the corresponding simulated ratios by box model. Thus, these prediction formulae were applied to map the spatiotemporal concentrations of the two aldehydes in summer over this city, combining CO and O3 monitoring data. In result, the area means of HCHO and CH3CHO over Beijing (except north rural areas) reached 11.8 and 3.6 ppb in 2021 summer, decreasing by 11.9% and 9.3% relative to 2019 respectively; and their spatial difference became smaller apparently within three years. Such spatiotemporal variations were approved by HCHO satellite observations. Overall, the aldehyde pollutions in this city are still severe and deserve more studies in future.

Dendritic Mesoporous Silica Nanoparticle-Supported Molybdena Catalysts for Propane Selective Oxidation: Catalytic Performance versus Molybdena Molecular Structure

Molybdena catalysts supported on dendritic mesoporous silica nanoparticles (Mo/DMSNs) were prepared by the impregnation method and evaluated for the selective oxidation of propane. The dendritic channels and high specific surface area of the DMSN support isolated the active components, which was beneficial for improving the dispersion of the Mo species. The identities of the active Mo species on the Mo/DMSN catalysts were determined using a combination of characterization techniques, and the relationship between the Mo loading and the structures of these Mo species was examined. Upon increasing the Mo loading, the mono-oxo O═Mo(O–Si)4 and di-oxo (O═)2Mo(O–Si)2 species underwent gradual polymerization to afford crystalline MoOx, where the mono-oxo and di-oxo species led to higher target product selectivities compared with the crystalline phase. In situ Raman spectroscopy results indicated that the highly dispersed monomolybdenum species were highly stable and resistant to carbon deposition during the reaction. Consequently, the 0.1Mo/DMSN, 0.5Mo/DMSN, and 1.0Mo/DMSN catalysts with monomolybdenum species exhibited higher propane conversions and target product selectivities than the catalysts bearing crystalline MoOx species. The highest yield (37.6%) of the target products (olefins and total aldehydes) was obtained over the 0.5Mo/DMSN catalyst at a temperature of 625 °C.

Multivariate prediction of Saliva Precipitation Index for relating selected chemical parameters of red wines to the sensory perception of astringency

Astringency is an essential sensory attribute of red wine closely related to the saliva precipitation upon contact with the wine. In this study a data matrix of 52 physico-chemical parameters was used to predict the Saliva Precipitation Index (SPI) in 110 Italian mono-varietal red wines using partial least squares regression (PLSr) with variable selection by Variable Importance for Projection (VIP) and the significance of regression coefficients. The final PLSr model, evaluated using a test data set, had 3 components and yielded an R2test of 0.630 and an RMSEtest of 0.994, with 19 independent variables whose regression coefficients were all significant at p < 0.05. Variables selected in the final model according to the decreasing magnitude of their absolute regression coefficient include the following: Procyanidin B1, Epicatechin terminal unit, Total aldehydes, Protein content, Vanillin assay, 520 nm, Polysaccharide content, Epigallocatechin PHL, Tartaric acid, Volatile acidity, Titratable acidity, Catechin terminal unit, Proanthocyanidin assay, pH, Tannin-Fe/Anthocyanin, Buffer capacity, Epigallocatechin PHL gallate, Catechin + epicatechin PHL, and Tannin-Fe. These results can be used to better understand the physico-chemical relationship underlying astringency in red wine.

Effects of quercetin on emissions of aldehydes from heated docosahexaenoic acid (DHA)-fortified soybean oil.

Home cooking has been considered as an indoor pollution problem since cooking oil fumes contain various toxic chemicals such as aldehydes. Fortifying edible oils with docosahexaenoic acid (DHA) has been applied to enhance the nutritional value of oils. This study designed a frying simulation system and examined the effect of oil type, DHA fortification, heating time, and addition of natural antioxidant on the emissions of aldehydes from heated oils. Results showed that linseed oil had the highest total aldehyde emissions, followed by soybean oil, peanut oil, and palm oil. Fortifying soybean oil with DHA increased the toxic aldehydes emitted. Quercetin, a flavonoid, significantly reduced aldehydes emitted from DHA-fortified soybean oil (by up to 39.80%) to levels similar to those of normal soybean oil. Further analysis showed that DHA-fortified soybean oil with quercetin had a significantly higher DHA and unsaturated fatty acids (UFAs) content than the control oil at each heating time point. The result indicated that quercetin inhibited emissions of aldehydes, at least in part, by protecting UFAs from oxidation. Collectively, quercetin could be used as a natural additive in DHA-fortified and normal cooking oils to reduce aldehyde emissions, indoor air pollution, and preserve functional DHA and other UFAs.

The role of metal nodes on Rh coordinated MOFs for Hydroformylation of n-butene

In this work, three MOF-based materials with highly dispersed Rh(I) were synthesized for hydroformylation of n-butene, namely Rh(I)/UiO-66, Rh(I)/MOF-5 and Rh(I)/MIL-101. The defect sites on the metal nodes of MOFs promoted the anchoring of Rh as a single active site. A high-performance Rh(I)/MOF-5 catalyst was obtained with the n-butene conversion and pentanal selectivity of 96.4% and 85.8%, respectively. In addition, it showed a good stability in the recycling tests after five runs. XRD, TEM, XPS, in situ DRIRTS confirmed that the metal nodes in MOFs modified the activity of the coordinated Rh catalyst by influencing the adsorption strength of CO. Combing the DFT results, we predicted that Rh(I)/MOF-5 catalyst with suitable CO adsorption energy could reduce the reaction energy barrier in CO insertion process, which was the rate-determining step of overall reaction, thus improving the selectivity of total aldehydes. This work broadened the application of MOFs as catalyst supports and provided assistance for the development of heterogeneous catalysts in hydroformylation of olefins.

Fatty acid metabolism-related genes are associated with flavor-presenting aldehydes in Chinese local chicken

Aldehydes are primary volatile organic compounds (VOCs) in local Chinese chicken meat and contribute green grass, fatty, citrus, and bitter almond aromas to chicken meat. To understand the genetic basis of these aldehyde VOC aromas, we used approximately 500 Chinese Jingxing Yellow (JXY) chickens to conduct genome-wide association studies (GWAS) on the flavor traits with the data of single nucleotide polymorphisms (SNPs) and insertions and deletions (INDELs). In total, 501 association variants (253 SNPs and 248 INDELs) were found to be suggestively (SNPs: p-value < 2.77e-06 and INDELs: p-value < 3.78e-05) associated with total aldehydes (the sum of nine aldehydes), hexanal, heptanal, benzaldehyde, (E,E)-2,4-nonadienal, octanal, (E)-2-decenal, nonanal, decanal, and octadecanal. Of them, six SNPs and 23 INDELs reached a genome-wide significance level (SNPs: p-value < 1.38e-07 and INDELs: p-value < 1.89e-06). Potential candidate aldehyde genes were functionally annotated for lipid metabolism, especially fatty acid-related pathways and phospholipid-related gene ontology (GO) terms. Moreover, the GWAS analysis of total aldehydes, hexanal, and nonanal generated the most significant signals, and phenotypic content differed between different genotypes at candidate gene-related loci. For total aldehydes and hexanal traits, candidate genes were annotated based on the significant and suggestive variants on chromosomes 3 and 8 with highly polymorphic linkage blocks. The following candidate genes were also identified: GALM, MAP4K3, GPCPD1, RPS6KA2, CRLS1, ASAP1, TRMT6, SDC1, PUM2, ALDH9A1, MGST3, GMEB1, MECR, LDLRAP1, GPAM and ACSL5. We also found that polyunsaturated fatty acids (PUFAs) (C18:2n6c linoleic acid and C18:3n3 linolenic acid) were significantly correlated with total aldehydes and hexanal contents. PUFAs are important aldehyde precursors, and consistently, our results suggested that candidate genes involved in fatty acid pathways and phospholipid GO terms were identified in association loci. This work provides an understanding of the genetic basis of aldehyde formation, which is a key flavor-forming compound.

Changes of Flavor Volatile Compounds on Different Storage Conditions of ANET-30 Peach Variety

Bu çalışma, özel sektör (Anadolu Etap-Çanakkale) meyve bahçelerinde üretilen ANET 30 şeftali çeşidi meyvelerinin depolanmaları süresince aroma bileşenlerindeki değişimin saptanması amacıyla yapılmıştır. Bu kapsamda meyveler, Kontrol, Xtend® torbalar içerisinde modifiye atmosfer paketleme (MAP), hasattan sonra 625 ppb dozunda 1-Metilsiklopropan (1-MCP) uygulanmış ve 1-MCP + MAP olmak üzere, 4 farklı şekilde 0±1°C sıcaklık ve %90±5 oransal nem koşullarında 60 gün süreyle depolanmış ve 20 gün arayla aroma bileşenlerindeki değişim saptanmıştır. Çalışmadan elde edilen bulgulara göre; ANET 30 meyvelerinde önemli aroma bileşeni aldehitler olarak saptanmış, depolamanın başlangıcında ortalama %81.33 olan toplam aldehitler depolama süresince azalarak %64.91 oranına düşmüştür. Ancak bu azalmanın derecesi uygulamalara göre farklılık göstermiştir. Aldehitler dışında laktonlar, alkoller, esterler, terpenler ve diğer aroma bileşenleri olarak saptanmış ve bunların depolama süresince değişimleri farklılık göstermiştir. Depolama süresi uzadıkça terpenler, laktonlar ve esterlerde önemli, alkollerde kısmen artış tespit edilmiş, bunlar dışındaki aroma bileşenler içerisinde hekzenlerde azalma saptanmıştır. Şeftali aromasını veren laktonlardaki artış 60 günlük depolama sonunda %150 oranına ulaşmıştır. Olgunluk ilerledikçe özgün aromayı veren bileşiklerde artış, aldehitlerde azalma saptanmıştır. Depolamanın başlangıcında 13 adet olan ana aroma bileşenlerin sayısı depolama süresince artış göstererek uygulamalara göre 19-30 sayısına ulaşmıştır. Aroma bileşenlerinin oluşumu depolama uygulamaları farklı düzeylerde gecikmiştir.

Study of Volatile Organic Compounds of Two Table Grapes (cv. Italia and Bronx Seedless) along Ripening in Vines Established in the Aegean Region (Turkey).

(1) Background: Italia is a seeded grape variety widely cultivated in the Aegean Region in Turkey, whereas Bronx Seedless is a seedless grape variety, preferred by consumers due to its pink berries and interesting flavor. The goal was to study the volatile compounds of these table grapes throughout berry ripeness. (2) Methods: The volatile compounds were analyzed by GC-MS in six different phenological stages (3) Results: Bronx Seedless grapes presented a higher content of seven terpenes, three aldehydes, one fatty acid, three alcohols, one C6 compound, total aldehydes and total alcohols, and a lower content of eleven terpenes, one fatty acid, four esters, one alcohol, four C6 compounds and its total content than Italia table grapes. The concentration of most of the volatile compounds analyzed increased from “begin of berry touch” to “berries ripe for harvest” stages. Terpenes content in both varieties at harvest was lower than 1.0 mg L−1. β-ionone presented the highest odor activity value (OAV) in both varieties. Bronx Seedless grapes presented higher OAV for (Z)-3-hexenal and cedrol, and lower hexanal to (E)-2-hexenal ratio than Italia grapes. (4) Conclusions: Both varieties could be classified as neutral aromatical varieties and it is probable that to achieve a better aromatic quality, Bronx Seedless should be harvested later than Italia.