Search Results (516)

Background: Wampee (Clausena lansium (Lour.) Skeels) is an understudied Rutaceae crop native to southern China, whose fruit features a complex aroma profile with simultaneous sour, sweet, bitter and astringent notes. Although bioactive compounds including flavonoids, alkaloids and volatile oils in wampee fruit have been partially characterized, the tissue-specific metabolic and transcriptional basis underlying its distinctive aroma formation remains largely unclear. Methods: We performed an integrated volatile metabolomic and transcriptomic analysis on the pericarp (peel) and flesh of wampee fruit across three cultivars (Shanyellowpi, Heijingang, Bingtangxin). Volatile metabolites were profiled via headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS), and transcriptome profiles were generated by RNA-Seq. Multi-omics integration was conducted using Procrustes analysis, gene–metabolite correlation network construction and weighted gene co-expression network analysis (WGCNA). Results: A total of 288 volatile metabolites were identified, representing the most comprehensive volatile inventory for C. lansium reported to date. Principal component analysis and partial least squares discriminant analysis revealed distinct volatile profiles between pericarp and flesh; terpenoids were the dominant chemical class, accounting for 71.56–91.48% of total volatiles in pericarp and 61.88–67.22% in flesh. Notably, organoheterocyclic compounds were significantly enriched in Shanyellowpi flesh (40.45%), forming a cultivar-specific metabolic signature absent in the other two cultivars. Transcriptomic analysis showed that phenylpropanoid biosynthesis was the most significantly enriched pathway among differentially expressed genes, followed by monoterpene biosynthesis and sesquiterpenoid biosynthesis. Procrustes analysis demonstrated a strong global concordance between the two omics layers (M² = 0.535, p < 0.001). Gene–metabolite correlation networks identified terpene synthase (TPS) genes (HP075360, HP217350) and oxidoreductase genes (SOD1, GST, 10HGO) as candidate co-regulators of terpenoid biosynthesis. WGCNA further prioritized TPS genes, cytochrome P450 genes and MYB transcription factor genes as key regulators driving volatile metabolic divergence between tissues. Conclusion: This study provides a comprehensive volatile and transcriptomic atlas of wampee fruit, and identifies tissue-specific and cultivar-specific metabolic signatures as well as their candidate regulatory genes. These findings advance our understanding of quality differentiation in Rutaceae fruits and lay a foundation for molecular breeding and flavor improvement of wampee. Full article

This study investigates the antioxidant efficacy and selectivity of a quercetagetin-rich extract (QG, 89% purity) from Tagetes erecta in soybean oil under accelerated storage conditions (65 °C, 56 days). Using gas chromatography–mass spectrometry (GC-MS) fatty acid profiling, Headspace Solid-Phase Microextraction Gas Chromatography–Mass Spectrometry (HS-SPME-GC-MS) volatile analysis, and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) chemometrics, QG at 200 ppm was compared against a solvent control and propyl gallate (PG). QG preserved polyunsaturated fatty acids 5.2-fold more effectively than the control (p < 0.01), though it was less effective than PG in terms of overall Polyunsaturated Fatty Acid (PUFA) preservation. OPLS-DA-VIP analysis identified hexanal, hexanoic acid, and (E)-2-nonenal as preferentially suppressed volatiles (inhibition rates: 74.2%, 100%, and 81.2%, respectively), exceeding the average total volatile reduction (65.7%). A quantitative Selectivity Index (SI) combined with kinetic analysis supported preferential—rather than non-selective—inhibition of specific oxidation endpoints. Structure–activity relationship analysis suggested that the selectivity of the QG-rich extract may be associated with the catechol B-ring and unique 6-hydroxyl substitution of quercetagetin, its major component. The extract’s purity corresponds to a registered feed additive (Ministry of Agriculture and Rural Affairs (MOA) No. 618, 2022), ensuring industrial applicability. These findings establish the quercetagetin-rich extract as a promising selective natural antioxidant for PUFA-rich oils. Full article

This preliminary within-animal study focuses on the comprehensive characterization of pork jowl (PJ) by comparing it with pork belly (PB), Boston butt (BB), and spare ribs (SR) collected from the same ten castrated Duroc × Landrace × Yorkshire (DLY) pigs; headspace volatile analysis used a matched subset of six pigs. Instrumental quality, proximate composition, amino-acid and fatty-acid profiles, low-field nuclear magnetic resonance (LF-NMR) water distribution and headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) volatile profiles were evaluated. PB exhibited the lowest shear force, hardness, and chewiness. Across the four pork cuts, crude protein content ranged from 16.87% to 18.10%, whereas crude fat content ranged from 13.03% to 22.20%. BB had the lowest crude fat content (13.03%) and relatively high protein (18.10%) and amino-acid contents. PJ showed highest content of monounsaturated fatty acids (MUFAs) and the lowest numerical atherogenic (AI) and thrombogenic indices (TI), but also the highest n-6/n-3 polyunsaturated fatty acids (PUFA) ratio. LF-NMR showed that PJ had the highest T₂₃ and P23 values, consistent with its higher cooking and centrifugal losses. Sixty-five headspace volatile compounds were tentatively identified under the standardized 80 °C HS-SPME conditions. OPLS-DA differentiated the four cuts, and ten compounds meeting the combined criteria of VIP > 1, q < 0.05, and OAV > 1 were retained as candidate discriminant aroma-relevant compounds. Overall, the four cuts exhibited distinct quality profiles: PJ combined a MUFA-rich lipid fraction with greater free-water mobility and water loss, PB showed the greatest instrumental tenderness, BB had the lowest crude fat content and relatively high protein and amino-acid contents, and SR exhibited the greatest headspace volatile abundance. The data provide a reference for cut-specific utilization of pork raw materials. Full article

Huangshui (HS), fermented grains (FG), and pit mud (PM) are closely connected during the fermentation of Nongxiangxing baijiu (NXB); however, the contribution of HS to the differences in flavor profiles across PM, FG, and distilled baijiu has not been fully elucidated. Herein, instrumental techniques of electronic nose (E-nose), headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS), and headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS) were used to compare the volatile profiles of HS, FG, PM, and two quality grades of NXB. E-nose analysis revealed that PM exhibited stronger signals related to sulfur-containing, organic, and terpene-associated compounds. Gas chromatography indicated that special-grade baijiu had a more favorable ethyl caproate/ethyl lactate ratio than superior-grade baijiu. Furthermore, HS-GC-IMS revealed different volatile profiles of the samples. Up to 183 volatile organic compounds (VOCs) were identified via HS-SPME-GC-MS, with esters and acids being the dominant classes. Multivariate analysis showed close relationships among HS, FG, and PM, and 35 VOCs were identified as important discriminatory compounds. These results suggest the differences and similarities in VOCs among the HS, FG, PM, and NXB samples, indicating that HS is chemically associated with both FG and PM. This study provides useful insights into HS utilization and quality regulation of NXB through the effective management of HS. Full article

This study investigated quality traits and volatile organic compounds (VOCs) in two winter wheat varieties with different gluten types (Xinliang 169, medium-strong gluten, and Xinliang 607, medium-weak gluten) across five grain-filling stages (5, 10, 20, 30, and 40 days after anthesis, DAA) under heated headspace conditions (80 °C). During grain filling, moisture and total soluble sugar (TSS) decreased significantly, whereas hardness, thousand-kernel weight (TKW), and starch content increased significantly. Protein followed a typical “high–low–high” pattern. Using headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC-MS), 80 and 125 VOCs were detected, respectively. A total of 19 preliminarily prioritized candidate odorants (e.g., 1-penten-3-one, 2,3-butanedione, and 3-methylbutanal) were screened using orthogonal partial least squares discriminant analysis (OPLS-DA, VIP > 1) and relative odor activity value (ROAV ≥ 1). Based on literature odor descriptors, the aroma profile shifted from green, malty notes during early grain filling to waxy, fatty, and grain-like notes during late grain filling. XL169 was characterized by grassy-green, malty, and fatty grain-like notes, whereas XL607 was dominated by creamy, buttery, and sweet-fruity woody notes. Correlation analysis revealed significant correlations between high-priority candidate odorants (2,3-butanedione, (E)-2-octenal, and 3-hydroxy-4,5-dimethyl-2(5H)-furanone) and quality traits (starch, TSS, and protein). These exploratory findings provide a preliminary reference profile for understanding how grain filling affects wheat VOCs. Full article

Volatile fingerprints provide useful information for characterizing Astragali Radix (AR), a food–medicine homologous plant material, but differences among wild, wild-simulated, and cultivated samples remain unclear. In this study, headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC–MS) and headspace gas chromatography–ion mobility spectrometry (HS-GC–IMS) were integrated with multivariate analysis and interpretable machine learning to characterize volatile profiles and identify candidate discriminatory compounds in 117 AR samples from different cultivation patterns. HS-SPME-GC–MS tentatively identified 29, 34, and 45 volatile compounds in wild, wild-simulated, and cultivated samples, respectively. Esters were the predominant class in all groups, although the relative abundance of esters and the overall chemical-class composition varied among cultivation patterns. HS-GC–IMS tentatively identified 57, 50, and 55 compounds, respectively, comprising mainly low-molecular-weight aldehydes, alcohols, and ketones and thereby providing complementary volatile fingerprint information. Partial least squares discriminant analysis (PLS-DA) showed that the volatile fingerprints captured cultivation-pattern-associated differences, with the HS-GC–IMS model showing clearer group separation. Random forest, support vector machine, and CatBoost models were further constructed using the HS-SPME-GC–MS profiling results. By integrating variable importance in projection (VIP) and SHapley Additive exPlanations (SHAP) values, γ-hexalactone, methyl eugenol, methyl (9Z,11E)-octadeca-9,11-dienoate, eugenol, and ethyl linoleate were selected as candidate discriminatory compounds. Based on the HS-GC–IMS results, 1-octen-3-one, pentyl acetate, (Z)-2-penten-1-ol, 2-heptanone, and the monomeric signal of 2-ethyl-6-methylpyrazine were also identified as candidate discriminatory compounds. These compounds may be related to fatty acid-derived metabolism, aromatic secondary metabolism, and terpenoid-related processes. The integration of two complementary volatile-analysis platforms with VIP- and SHAP-based interpretation provided broader coverage of volatile features and improved the interpretability of candidate-compound screening. These findings provide an interpretable analytical workflow and candidate discriminatory compounds that may support future rapid screening, cultivation-pattern authentication, and volatile-profile-based differentiation of AR, pending independent external validation. Full article

The spotted-wing drosophila, Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), is an invasive pest causing substantial economic losses in berry production worldwide. Reliable monitoring is essential for effective integrated pest management; however, information on the field performance of locally produced vinegar-based attractants remains limited. This study compared the attractiveness of four vinegar-based attractants (homemade grape vinegar, homemade hawthorn vinegar, homemade apple vinegar, and commercial apple vinegar) for monitoring D. suzukii in blackberry (Rubus spp.) and blueberry (Vaccinium spp.) orchards in southeastern Türkiye during the 2023 and 2024 growing seasons. In addition, the volatile organic compound (VOC) profiles of the attractants were characterized using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC–MS). A total of 80,571 adult flies were captured during the study. Significant differences among attractants were detected in all host plant–year combinations (one-way ANOVA, p < 0.001). Generalized linear mixed model analysis further demonstrated significant effects of the host plant, attractant type, sampling week, and year on weekly trap captures (p < 0.05). Homemade grape vinegar consistently produced the highest trap captures, whereas commercial apple vinegar showed the lowest trapping performance. Fourteen volatile compounds belonging mainly to carboxylic acids, alcohols, esters, aldehydes, and monoterpenes were identified, revealing differences in the volatile profiles of the evaluated attractants. Overall, homemade grape vinegar proved to be the most effective vinegar-based attractant under the conditions of this study and represents a practical, low-cost option for monitoring D. suzukii in berry orchards. Further studies incorporating replicated chemical analyses and behavioural bioassays are needed to clarify the contribution of individual volatile compounds to insect attraction. Full article

The lipoxygenase (LOX) pathway plays a crucial role in the biosynthesis of characteristic aroma compounds in fruit. Despite the progress in understanding the LOX pathway in model plants like tomato, the distinct roles of individual members within the LOX gene family in flavor formation in the complex octoploid strawberry are still not fully understood. In this study, we identified 13 LOX genes in the strawberry genome and focused on a specific lipoxygenase gene, designated FaLOX11, which exhibited the highest expression during fruit ripening. Spatiotemporal expression analysis revealed that FaLOX11 expression was significantly correlated with 3-hexenal accumulation, quantified via headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS). Functional characterization via transient overexpression of FaLOX11 in strawberry fruits resulted in a significant increase in C6 volatile content, specifically a ~72% increase in 3-hexenal content. Conversely, RNA interference (RNAi)-mediated transient silencing of FaLOX11 significantly downregulated the expression of this gene and led to a marked reduction in the production of these key aroma compounds. Our findings demonstrate that FaLOX11 acts as a positive regulator of C6 aldehyde and alcohol biosynthesis, thereby playing a pivotal role in determining the characteristic aroma profile of strawberry fruit. This study provides new insights into the LOX pathway in strawberry and lays a solid molecular foundation for improving strawberry flavor quality. Full article

Quince (Cydonia oblonga Mill.) is an important fruit crop, yet a systematic quality evaluation framework is lacking. This study comprehensively characterized multiple germplasms from distinct production areas. An integrated strategy combining physicochemical analysis, FT-MIR (Fourier transform mid-infrared spectroscopy), electronic nose (E-nose), headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS), and chemometrics was employed. Significant variations were observed among accessions: certain varieties were observed to exhibit the highest pectin (1.86%) and total phenolic content (143.40 mg/100 g), while others showed superior firmness and titratable acidity. β-Damascenone in one accession was found to have an exceptionally high odor activity value (OAV) of 265.05. Multivariate analysis, including PLS-DA and OPLS-DA, effectively discriminated among quince accessions, with PLS-DA achieving 100% classification accuracy, and tentatively identified 18 key markers (VIP > 1) for accession discrimination. Loading scatter plot analysis further validated the contribution of these markers to the separation between accessions. However, due to the limited sample size (n = 18) and partial confounding between cultivar and origin, these findings should be considered exploratory and require validation in larger independent studies. This work provides preliminary insights into the diversity and geographical patterns of quality and flavor traits in quince germplasm, offering a preliminary foundation for germplasm evaluation and targeted utilization. Full article

Beer quality assessment increasingly requires rapid and scalable analytical tools for product discrimination and authenticity control. In this study, a data-driven metal oxide semiconductor (MOX) chemosensing approach was investigated for the discrimination of commercial lager beers with different alcohol contents and brands. Alcoholic and alcohol-free beer samples from four commercial brands were analyzed using a six-element SnO₂-based MOX sensor array, and the resulting response patterns were classified using supervised machine-learning algorithms. Headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC–MS) was employed as a reference technique to characterize volatile organic compound profiles and support the interpretation of sensor-based fingerprints. GC–MS analysis highlighted a shared volatile backbone dominated by fermentation-related compounds, while also revealing brand- and category-dependent differences in VOC distribution. The MOX sensor array captured these differences as multidimensional volatile fingerprints. Machine-learning models achieved high classification performance in brand-matched alcoholic versus alcohol-free comparisons, with balanced accuracy ranging from 0.937 to 1.000, while brand discrimination within the same category reached balanced accuracy values of 0.875 (alcoholic) and 0.933 (alcohol-free). These results highlight MOX-based chemosensing combined with data-driven analysis as a rapid, portable platform for beer discrimination, with applications in food quality screening, authenticity assessment, and at-line monitoring. Full article

Marine macroalgae are now considered potential sources of renewable feedstocks to produce valuable bioactive compounds. However, the species-specific volatilomes and their correlation with antioxidant capacity remains largely unknown. This study aimed to investigate the volatilomic fingerprint, total phenolic content (TPC), total flavonoids content (TFC) and antioxidant capacity of four macroalgae belonging to distinct taxonomic groups: Rugulopteryx okamurae (brown algae), Asparagopsis taxiformis (red algae), Caulerpa webbiana (green algae), and coralline algae. To achieve this purpose, the volatilomic fingerprint was established using headspace solid-phase microextraction tandem gas chromatography–mass spectrometry (HS-SPME/GC-MS), and the TPC, TFC, and antioxidant capacity were evaluated using in chemico assays. A total of 59 volatile organic compounds (VOCs) were identified across the marine macroalgae, encompassing carbonyl compounds (on average, 40.7 ± 13.4% of total volatilomic fraction), hydrocarbons (17.0 ± 8.3%), organohalogens (23.0 ± 10.8%), terpenoids (6.5 ± 2.0%), alcohols (4.5 ± 2.0%), and the remaining chemical families showed a contribution lower than 5% to the total volatilomic fingerprint. Multivariate statistical analyses revealed significant differences (p < 0.05) in the volatilomic fingerprint among the macroalgae investigated, allowing clear discrimination between species. Organohalogen compounds emerged as key discriminant features for C. webbiana and A. taxiformis algae, while hydrocarbons were characteristic of the R. okamurae. Despite taxonomic differences, hexanal, benzaldehyde and β-ionone were VOCs found across all samples. Regarding bioactivity, R. okamurae exhibited the highest TPC (144 mgGAE/100 g DW), TFC (69 ± 6 mg QE/100 g DW), and antioxidant capacity. These findings confirm the large variability of the volatilomes of the different species of macroalgae and demonstrate the power of the HS-SPME/GC-MS, chemometric, and antioxidant analysis strategy for the differentiation of species and the identification of VOCs with valorization potential, helping to transform invasive or unused biomass of these species into new, sustainable bioproducts through emerging technological and biorefinery applications. Full article

The American cranberry (Vaccinium macrocarpon Aiton) is widely appreciated for its high nutritional value and characteristic volatile profile, making it an important raw material for the food industry, particularly in the sector of minimally processed products. However, thermal processing may significantly alter its volatile composition, leading to aroma losses and degradation of product quality. Therefore, understanding the impact of processing conditions on aroma stability is essential for developing new post-harvest technologies that preserve the volatile profiles of processed fruit products. The aim of this study was to evaluate the effect of thermal treatment and protein matrix modification on the volatile organic compound (VOC) profile of fresh-cut cranberry fruit. Samples were heated at 50, 100, and 200 °C, with and without gelatin addition as a protein-based matrix modifier. VOCs were analysed using headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME–GC–MS). High-temperature treatment (200 °C) resulted in substantial changes in the volatile composition of the reference cranberry fruit and contributed to the complete loss of characteristic native terpenoids. The addition of gelatin significantly improved the retention of hydrophobic volatiles under thermal stress, maintaining D-limonene at 20.3% of the total volatile fraction, whereas this compound was absent in samples processed without the modifier. Furthermore, gelatin successfully altered the course of thermally induced reactions, reducing undesirable furfural formation from 23.95% to 7.28%. These changes indicate that protein-assisted matrix modification can effectively limit aroma degradation and preserve the volatile profile during thermal processing. The findings demonstrate the potential of this approach as a novel technological strategy for enhancing aroma stability, reducing processing-related quality losses, and supporting the development of fresh-cut cranberry products with enhanced volatile compound retention. Full article

The effects of different rootstocks on the grape quality and volatile aromatic compounds of ‘Shine Muscat’ were investigated. The basic physicochemical parameters of berries from five scion–rootstock combinations (SM-Beta, SM-SO4, SM-5C, SM-Fercal, SM-YN2) and own-rooted ‘Shine Muscat’ grape were measured, and their volatile aromatic compounds were determined using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography–mass spectrometry (GC-MS). Our results showed that the SM-YN2 combination exhibited the highest berry weight, and increased by 28.13% compared with SM self-rooted seedling. In addition, the ‘5C’ and ‘YN2’ rootstocks could better maintain total soluble solids (TSS), titratable acidity (TA), TSS/TA and pH in the berries, whereas the ‘Beta’, ‘SO4’ and ‘Fercal’ rootstocks impaired TSS. Volatile profiling identified 841 volatile compounds classified into 15 categories, among which terpenoids constituted the predominant contributors to berry aroma. Furthermore, 22 characteristic aroma compounds were screened, and linalool presented the highest concentration among all terpenoids in ‘Shine Muscat’ fruit. Odor activity values (OAVs) and aroma proportion analyses further revealed that linalool is the key compound for the characteristic ‘muscat’ aroma of ‘Shine Muscat’. In addition, the SM-YN2 combination exhibited 31.96% and 4.61% higher concentration and proportion of linalool compared to own-rooted vines. Notably, with the exception of ‘YN2’, ‘Beta’, ‘SO4’, ‘5C’ and ’Fercal’ downregulated the expressions of one or more terpenoid synthesis-related genes. In conclusion, grafting onto rootstock could improve berry quality, particularly the ‘YN2’ rootstock, which yielded ‘Shine Muscat’ grapes with the highest overall quality. As a resource of the East Asian grape group, ‘YN2’ can be utilized as a rootstock in future production. Full article

High-altitude environments provide a favorable basis for tea quality formation, but suitable processing parameters for high-altitude Oolong Tea (HAOT, Camellia sinensis (L.) O. Kuntze) remain unclear. This study optimized key processing parameters for HAOT using a three-factor, three-level orthogonal design involving withering method, shaking intensity and standing time. Sensory evaluation, quantitative descriptive analysis (QDA), macro-compositions determination, headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS), multivariate statistics and correlation analysis were used to clarify quality differences and their chemical basis. Leaf anatomical observation showed that high-altitude fresh leaves had a thicker cuticle and more compact mesophyll structure, suggesting the need for targeted processing regulation. Range analysis indicated that shaking intensity had the largest R value for sensory scores, followed by withering method, whereas standing time showed a comparatively small R value. The favorable combination was combined withering, heavy shaking (6 rounds) and 60 min standing, hereafter referred to as FHM. FHM showed the highest floral and fruity aroma scores and produced a mellow, full-bodied taste with a sweet aftertaste. It also contained significantly higher flavonoid and soluble sugar levels than the other processing combinations. A total of 65 volatile organic compounds were detected, with terpenoids and esters as the dominant classes. ROAV analysis identified geraniol, linalool, β-ionone, (E)-nerolidol and benzaldehyde as representative major aroma-active compounds, while geraniol and linalool were especially prominent in FHM. Correlation analysis further linked flavonoids and soluble sugars with positive taste attributes, and linalool and geraniol with floral–fruity aroma. These results provide a practical basis for optimizing HAOT processing and improving product quality. Full article

Volatile composition is a core trait that determines the ornamental and application value of Rosa flowers. In the current study, the volatile profiles of freeze-dried Rosa gallica flowers were comprehensively characterized via gas chromatography-mass spectrometry (GC-MS), coupled with heatmap clustering, principal component analysis (PCA), and relative odor activity value (rOAV) determination. A total of 181 volatile compounds were identified, and distinct volatile profiles were observed between flower samples treated with headspace extraction (RG-HS) and solid-phase microextraction (RG-SPME). Alcohols were the dominant volatile class in RG-SPME, whereas aldehydes were abundant in the RG-HS group. In terms of aroma characteristics, RG-SPME presented stronger green, floral, citrus, and fatty odors, while RG-HS exhibited a more pronounced fruity note. Moreover, sulfurous and dairy notes were unique to RG-SPME and RG-HS, respectively. Additionally, 27 volatiles showed rOAV above one, with 2,3-butanedione and trans-citral having the greatest rOAV value of 100, were identified as the potential aroma-active contributors to butter-like and citrus odors in RG-HS and RG-SPME, respectively. These results provide a methodological reference for volatile profiling of R. gallica flowers, and support the selection of appropriate extraction methods for future research and resource utilization. Full article