Solid-phase Microextraction Gas Chromatography Research Articles

Effects of pits of different ages on ethyl acetate and its metabolism-related microorganisms during strong-flavor Baijiu fermentation

The esters are the most important flavor components in Baijiu as their species and content decide the style of Baijiu. During the formation of esters, pits play important roles. In this study, the main esters and their related microorganisms in different years of pits (5, 35 and 100 years) of strong-flavor Baijiu were comprehensively researched by headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) and amplicon sequencing. A total of 690 bacterial genera and 155 fungal genera were detected. The microbial composition of ZPs (fermented grains) from 100 years pit was the most abundant at the genus level. A total of 177 volatile flavor components were observed, including 80 esters, 42 alcohols, 21 acids, 10 ketones and 11 aldehydes. Ethyl acetate was the lowest and ethyl caproate was relatively high in 100 years pit. 15 genera, including Lactobacillus, Pichia, Issatchenkia, Saccharomyces, and Aspergillus, were positively related to the formation of four major esters and their precursors. The research demonstrated that 100 years pit was benefit for maintaining microbial diversity and controlling ethyl acetate. This study is helpful for understanding the microbial composition and succession in the fermentation process of strong-flavor Baijiu, and revealing the complex relationships between dominant genera, physicochemical properties and volatile flavor components.

Inter- and intra-varietal clonal differences influence the aroma compound profiles of wines analyzed by GC-MS and GC-IMS.

To investigate the impact of genetic factors on wine aroma, wines made from 22 clones of five grape varieties (Vitis vinifera L.) were used to analyze the volatile compounds by headspace solid phase microextraction gas chromatography mass spectrometer (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS). Results showed that 52 and 49 aroma compounds were identified from 22 clones of wines by two technologies, respectively. Esters were the most abundant compounds, followed by alcohols and aldehydes. The aroma profiles demonstrated significant varietal and clonal diversity, the clones with the highest aroma compound content were CH VCR6, PN VCR20, CS VCR11, ML VCR101, and CF 678. Partial least squares discriminant analysis (PLS-DA) identified decanoic acid, 1-heptanol, diethyl succinate, ethyl octanoate, and octanal as key biomarkers for distinguishing 22 clones of wines. Our results revealed that white wine CH VCR6 and red wine CS VCR11 possessed the most complex aromas. These findings address the research gap concerning the genetic determinants of wine aroma, highlighting the significance of grape variety and clone selection in developing wines with desirable sensory attributes.

Supercritical fluid extrusion of pea flour and pea protein concentrate: Effects on off-flavor removal and sensory improvement.

This study was intended to provide a novel process that fills a knowledge gap in relation to the enhancement of pulses utilization. The primary goal was to develop an experimental framework for using a high-pressure supercritical fluid extruder (SCFX) as a continuous bioreactor to produce off-flavor reduced and functionally superior pulse flours and protein concentrates in a single step. The current study focused on using SCFX processing to remove off-flavor from pulse flour and protein concentrates, enhancing the quality, acceptability, and marketability of pulse-based products. Supercritical carbon dioxide (SC-CO2), a well-known green solvent, was employed in combination with an extrusion system to achieve off-flavor reduction at larger scale. Using various methods such as headspace solid-phase microextraction-gas chromatography mass-spectroscopy (HS-SPME-GC-MS) and sensory evaluation, this study demonstrated that SCFX significantly reduced the off-flavor in pea flour (PF) and pea protein concentrate (PPC). HS-SPME-GC-MS analyses identified major off-flavor compounds in unextruded PF and PPC, including 1-hexanol, 1-octanol, 1-nonanol, nonanal, and 2-alkyl methoxypyrazines. Following SCFX treatment, all these compounds except nonanal were removed. Total off-flavor compound concentration dropped from 923 to 126.5ng/g in PF, and from 571.7 to 65.9ng/g in pea protein concentrate PPC after SCFX treatment. Sensory evaluation corroborated these HS-SPME-GC-MS findings, showing that over 80% of the participants could accurately distinguish the extruded samples from the unextruded ones, perceiving the treated samples as having the least beany flavor. These findings highlight the efficacy of SCFX processing in enhancing the sensory profile of pulse-based products by removing off-flavor compounds.

Unveiling the Floral Scent Dynamics of Calamondin (Citrus × microcarpa) Across Developmental Stages

The calamondin (Citrus × microcarpa) is highly valued for its ornamental appeal and rich aromatic compounds, making it suitable for therapeutic gardens and widely applicable in the cosmetics, food, pharmaceutical, and perfume industries. Despite its importance, there is a lack of research on its floral volatiles. This study utilized headspace solid-phase microextraction gas chromatography–mass spectrometry (HS–SPME–GC–MS) to detect the volatile organic compounds (VOCs) of calamondin at different floral developmental stages: bud (BS), half-open (HS), full bloom (FS), and senescence (SS). Multivariate statistical analysis was employed to elucidate the aromatic characteristics. The results identified 67 VOCs across the four stages, including forty-eight terpenoids, six esters, five aromatics, four aldehydes, one olefin, one alcohol, and two others. Thirty-three VOCs were common across all stages, while BS, HS, FS, and SS had three, three, four, and nine unique VOCs, respectively. The total VOC content increased initially and then decreased as the flowers developed, with terpenoids being the predominant compounds, accounting for over 90% of the total emissions at all stages. Principal component analysis and hierarchical cluster analysis confirmed significant differences in VOC profiles at different stages. Partial least squares discriminant analysis identified five VOCs with variable importance in projection (VIP) values greater than one, including limonene, linalool, β-pinene, germacrene D, and β-ocimene, indicating their varying emission levels across stages. These findings enhance our understanding of the VOC characteristics of calamondin flowers and provide a scientific basis for further ornamental and industrial applications.

Assessment of Characteristic Flavor and Taste Quality of Sugarcane Wine Fermented with Different Cultivars of Sugarcane

In order to explore the variation in volatile compounds and aroma profiles of different varieties of sugarcane wine, volatile compounds of 14 different varieties of sugarcane wine were analyzed by headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) and an electronic sensory system. The differences in flavor substances of different cultivars of sugarcane were assessed by orthogonal partial least squares discriminant analysis (OPLS-DA) discriminant model and relative odor activity value (ROAV) combined with multivariate statistical methods. The results showed that a total of sixty major volatile compounds, i.e., 27 esters, 15 alcohols, eight acids, three phenols, four aldehydes and ketones, and four others, were identified in 14 types of sugarcane wine. Seven key aroma compounds were screened out: ethyl caprylate, ethyl caprate, ethyl acetate, ethyl laurate, n-decanoic acid, 2,4-di-tert-butylphenol, and 2-phenylethanol and three differential aromas, i.e., ethyl palmitate, isobutyl alcohol, and caprylic acid. The electronic nose and electronic tongue analysis technology can effectively distinguish the aroma and taste of 14 sugarcane wines. It is confirmed that the aroma and taste of 14 sugarcane wines have differences in distribution patterns, and the results are consistent with the analysis and assessment of volatile compounds of sugarcane wine. The results of this study provide technical support for the production and quality improvement of sugarcane wine.

Influence of indigenous non-Saccharomyces yeast strains on the physicochemical and sensory properties of wine fermentation: a promising approach to enhancing wine quality.

This study explores the potential of indigenous non-Saccharomyces yeasts isolated from Vitis vinifera L. grape skins to improve the quality of regional wines by enhancing their physicochemical and sensory characteristics. Five promising yeast strains were identified at different stages of fermentation: Hanseniaspora opuntiae (J1Y-T1), H. guilliermondii (Y5P-T5), H. uvarum (JF3-T1N), Pichia kudriavzevii (Y8P-T8), and Starmerella bacillaris (WMP4-T4). Among these, H. uvarum and S. bacillaris were particularly noteworthy due to their superior alcohol production, achieving levels of 8.16 ± 0.05% and 8.04 ± 0.04% (v/v), respectively, and demonstrating higher alcohol tolerance even in later fermentation stages. Hanseniaspora uvarum also showed exceptional resilience, with a half-life of 3.34 ± 0.03 days and a Km value of 1.0200 ± 0.0100 mol L⁻¹, achieving the highest biomass even in the later stages of fermentation. High-Performance Liquid Chromatography analysis revealed that while tartaric acid levels remained constant, malic acid content decreased, and acetic acid was produced by all strains. Solid-Phase Microextraction-Gas Chromatography Mass Spectrometry identified ethyl acetate as the dominant volatile compound, with H. uvarum producing the highest concentration (43.411 ± 1.602%), contributing to a fruitier aroma and flavor. The combined attributes of H. uvarum higher alcohol content, enhanced fruity notes, improved clarity, lower acetic acid (0.52 ± 0.03 g L⁻¹), and significant residual sugar (162.37 ± 2.48 g L⁻¹) make it a promising candidate for improving the overall quality of regional wines. Incorporating H. uvarum into mixed starter cultures with specific Saccharomyces strains could further optimize the wine fermentation process.

Influence of Apple Juice Type on Fermentation Process and Volatile Compounds of Hard Apple Cider

Fermented apple cider is a refreshing alcoholic drink known since ancient times, and it is obtained by fermenting apple fruit juice. Using the standards of alcohol concentration (up to 8%) and carbonation, it belongs to drinks similar to beer. It can be produced using wild yeasts, but currently a fermentation starter can be purchased. This work aims to produce fermented cider using commercial pasteurized juices: clear apple juice and organic cloudy juice using commercial yeast for cider production. After fermentation, the physico-chemical characteristics of the drink were determined, alongside volatile compounds of the freshly produced ciders, as well after 1, 2, and 3 weeks of maturation. Acids, alcohols, carbonyl compounds, terpenes, esters, and volatile phenols were determined using headspace–solid phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC/MS). The results show that the fermentation was slower (14 days) in the cloudy juice in contrast to the sample produced from clear apple juice (10 days). Also, the volatile compounds related to aroma were abundantly found in the cider produced from cloudy apple juice compared to the cider produced from the clear apple juice. The conducted sensory analysis was in favor of cloudy juice.

Improving Quality Profiles of Summer-Autumn Tea Through the Synergistic Fermentation with Three Fungal Strains

The co-fermentation of summer-autumn tea with Aspergillus niger and Eurotium cristatum effectively reduces bitterness and astringency, enhances flavor and quality, and increases market appeal and economic value. This study investigated the dynamic changes in metabolites, flavor characteristics and quality indicators of summer-autumn tea during fermentation. Using headspace solid-phase microextraction gas chromatography (HS-SPME-GC-MS), 96 key metabolites were identified, significantly enhancing the tea's aroma and flavor. On the fourth day of fermentation, the content of ester catechins (EGCG, ECG) decreased by 79.44% and 79.57%, respectively, while non-ester catechins (EGC, C, EC) increased by 175.47%, 228.18%, and 138.73%, respectively. Additionally, the gallic acid content increased by 755.58%, along with rises in free amino acids and soluble sugars. Sensory evaluation focused on taste, soup color, and aroma, resulting in a total score of 80.67. The intensity of astringency, bitterness, and sourness in the tea infusion gradually decreased, while sweetness, umami, and aroma intensified. These findings underscore the significant role of the synergistic action of the three strains in developing the unique flavor profile of summer-autumn tea during fermentation. This research lays the foundation for quality control and resource development in the processing of summer-autumn tea.

Characteristic aroma identification of differentially colored peach fruits based on HS-SPME-GC–MS

Aromatic components are vital for the flavor profile of peaches. This study investigated the aroma compounds of 20 differential peach cultivars using headspace solid-phase microextraction-gas chromatography–mass spectrometry (HS-SPME-GC–MS). A total of 82 distinct aromas were identified, comprising 6 lactones, 16 esters, 24 alcohols, 5 aldehydes, 12 ketones, and 19 other compounds. The yellow peach cultivar ‘Tropic Beauty’ exhibited the highest aroma content, whereas ‘Xiahui 5’ topped the white peaches. Furthermore, 11 key aromas were identified based on their odor activity values (OAVs), with hexanal demonstrating the highest average OAV of 1333.27. The top ten cultivars were ranked as follows: ‘Tropic Beauty’, ‘NJN76’, ‘Vega’, ‘Xiahui 5’, ‘Zhongyoujinshuai’, ‘Troubador’, ‘Flordaguard’, ‘Ruiguang 35’, ‘Jinhualu’, and ‘Xiacui’. These results lay a strong foundation for assessing peach flavor and developing breeding strategies for peach cultivars.

Risk assessment of migrants released from multilayer packaging materials: Direct immersion-solid-phase microextraction coupled to gas chromatography-mass spectrometry

Milk is commonly contained in plastic multilayer pouches or cartons. Substances in these food packaging materials, such as additives, processing aids, degradation products, and residues may migrate into the milk, thereby causing contamination and human health risks. The migration of substances from six plastic multilayer pouches and five multilayer cartons that are commonly used as milk packaging materials into a model food (50 % ethanol) was studied. A direct immersion -solid phase microextraction-gas chromatography mass spectrometry (DI-SPME-GC-MS) method was optimized for the identification and quantification of the migrants. The optimal conditions were determined to be 60 min extraction time, 75 °C extraction temperature, and 1000 rpm stirring rate. Using this method, 36 compounds were found to have migrated into the milk, including several additives (such as bis(2-ethylhexyl) phthalate, acetyl tributyl citrate and erucamide), several degradation products (such as 2,4-di-tert-butylphenol and 7,9-di-tert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione), an initiator residue, and some solvents. A risk assessment was then conducted, and it was found that the exposure of certain substances from six plastic multilayer pouches into 50 % ethanol might pose potential human health risk. Our study showed that DI-SPME-GC-MS is a fast and efficient migration detection method, and our findings provide an important reference for the risk assessment of the potential migration of toxic substances from multilayer packaging materials into milk.

Enhanced Analysis of Carcinogens and Nutritional Profile of Vitis vinifera by Employing Pulsed Electric Field.

Solid Phase Microextraction-Gas Chromatography Triple Quadrupole Mass Spectrometry (SPME-GC-TQ/MS) was optimized and validated to specifically analyze aldehydes and furans after drying Vitis vinifera grape variety by conventional as well as modern pre-drying technique i.e. pulsed electric field (PEF). Analytical method was validated in terms of linearity (R 2), recovery (%), relative standard deviation (% RSD), limit of detection (LOD) and limit of quantification (LOQ). Sample pre-treatment with PEF (1 kV/cm) followed by drying at 65°C produced dried product with fewer chemical changes in the composition than convective hot air drying. Meanwhile, nutritional parameters including polyphenolics, amino acids, fatty acids and sugars profiles were also extensively investigated to get deeper insights into the effect of drying treatments on the nutritional quality of dried product. Conclusively, sample pre-treatment on relatively lower PEF voltage, followed by drying at minimum temperature with longer time duration can preserve nutritional quality of product by forming less harmful compounds.

Preparation and flavor characteristics of plant-based meat flavoring by mixed fermentation of multiple strains

In this study, plant-based meat flavoring was prepared by mixed fermentation and thermal reaction. Based on the changes of amino acid nitrogen, reducing sugar, and total acid during the fermentation process and combined with sensory evaluation, the optimal fermentation conditions were determined as 4 % total inoculation amount of Monascus purpureus, Actinomucor elegans, and Bacillus subtilis with an inoculation ratio of 1:1:1, and 36 h of fermentation time. The odor characterization of meat flavoring was identified by solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS), aroma extract dilution analysis (AEDA), quantitative measurements, odor activity value (OAV) and aroma recombination and omission experiments. 64 volatile compounds and 28 odorants were identified. The compounds with FD ≥ 27 were precisely quantified by five-point standard calibration curve and OAVs were calculated, and those with OAV ≥ 1 were subjected to aroma recombination and omission experiments. Finally, furfuryl mercaptan, difurfuryl disulfide, 4-methyl-5-ethylthiazole, 1-octanal, and 2-acetylthiophene were determined to be the key aroma-active compounds. These compounds have been recognized as key aroma-active compounds or detected in other meats or meat flavorings. In this study, we prepared plant-based meat flavoring through mixed fermentation, and provide new ideas for the development of plant-based thermal reaction meat flavoring process.

Influences of lactic acid bacteria strains on the flavor profiles, metabolites and quality characteristics of red yeast rice produced by solid-state fermentation

Red yeast rice (RYR) as a traditional fermented food produced by inoculation of the Monascus genus into steamed rice through solid-state fermentation, has been used intensively for thousands of years in China. Herein, we investigated the flavor profiles, metabolites and quality characteristics of RYR produced by mix fermentation with lactic acid bacteria (LAB) using the headspace solid phase microextraction gas chromatography–mass spectrometry (HS–SPME–GCMS) approach integrated with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS). 56 volatile organic compounds (VOCs) and 1287 non-volatile metabolites were identified and classified into eight classes, the inoculation of Lactiplantibacillus plantarum (LP) and Limosilactobacillus fermentum (LF) increased VOCs and enhanced the flavor characteristics of RYR, with LP being the more significant. The KEGG pathway enrichment analysis revealed that most of the differential metabolites were enriched in amino acid metabolism when integrating volatile and non-volatile omics data, meanwhile, the addition of LAB promoted the metabolism of amino acid, alcohols, fatty acid and some flavonoids, in particular, amino acid metabolism was almost upregulated in the LP group. Therefore, this study highlights the tremendous potential of LAB in improving the flavor quality of RYR. This study provides novel insights into RYR fermentation processes and establishes a theoretical foundation for developing and applying new RYR products.

Characterization of the flavor profile of four major Chinese carps using HS-SPME-GC–MS combined with ultra-fasted gas chromatography-electronic nose

The four major Chinese carps are highly popular for their distinctive nutritional benefits. However, the differences in flavor among these carps remain unclear. This study investigated the flavor profiles of these carps using headspace solid-phase micro-extraction gas chromatography–mass spectrometry (HS-SPME-GC/MS) combined with ultra-fasted gas chromatography electronic nose (GC E-nose). The four major Chinese carps had high protein content (16.68–18.61 %) and low fat levels (0.42–1.29 %). A total of 45 volatile compounds were identified in these carps. Both the GC E-nose and HS-SPME-GC–MS results consistently showed significant flavor profiles differences among these carps, with Ctenopharyngodon Idella (CI) exhibiting the most pronounced distinctions compared to the other three species. Based on VIP >1 and p < 0.05, 10 key compounds including 2-Nonanone, Cyclodecanol, Eugenol, 1,3-Cyclooctadiene, etc., largely contributed to the distinctive overall flavor profile of four major Chinese carps derived mainly from amino acid and fatty acid metabolism.

The dynamic changes and correlations between biochemical properties, flavor and microbial community during fermentation of asparagus by-products

Asparagus by-products are the promising resource that urgently need to be re-valorized. This study investigated the dynamic changes in physicochemical properties, organic acids, free amino acids, volatile flavor compounds, microbial succession, and their correlations during 7-day spontaneous fermentation of asparagus by-products. Dominant organic acids (lactic acid and acetic acid) and free amino acids (Ser, Glu, and Ala) increased with fermentation time, with lactic acid reaching 7.73 ± 0.05 mg/mL and Ser increasing 56-fold after 7 days. A total of 58 volatile flavor compounds were identified using headspace solid-phase microextraction-gas chromatography–mass spectrometry (HS-SPEM/GC–MS), with esters, alcohols and acids as the main volatile flavor compounds. Fourteen volatile flavor compounds had odor activity value >1. High-throughput sequencing showed Firmicutes and Proteobacteria as the main bacterial phyla, dominated by lactic acid bacteria (Levilactobacillus, Lactiplantibacillus, Weissella). Correlation analysis revealed that five bacterial genera (Levilactobacillus, Lactiplantibacillus, Enterobacter, Pediococcus and Acetobacter) were highly correlated with organic acids, free amino acids, and volatile flavor compounds, indicating their pivotal role in forming the characteristic flavor of fermented asparagus by-products (FAPS). This study provides new insights into the flavor and microbial profile of FAPS, offering a strategy for value-added processing and industrial production.

Changes in volatile flavors during the fermentation of tomato (Solanum lycopersicum L.) juice and its storage stabilization

Flavor is a crucial indicators of the quality of fermented tomato juice; however, there has been limited research in this area. Herein, headspace solid-phase microextraction gas chromatography–mass spectrometry was used to analyze the volatile metabolites at different stages during FTJ fermentation. 131 volatile organic compounds (VOCs) were identified, with alcohols, acids, and esters as the main compounds. The content of superoxide dismutase (SOD) and lycopene (LYC) had a positive correlation with methyl salicylate, ethyl acetate, and linalyl acetate. Subsequently, the storage stability of FTJ was evaluated at temperatures of 4 °C, 25 °C, and 37 °C over a period of 45 d, revealing that the quality of FTJ decreased with increasing storage temperature. The shelf life of FTJ under different storage conditions was determined using SOD activity and LYC content as quality indicators. The final shelf life was 47 d at 37 °C, 69 d at 25 °C, and 123 d at 4 °C.

Chemical profile and in-vitro bioactivities of three types of yellow teas processed from different tenderness of young shoots of Huoshanjinjizhong (Camellia sinensis var. sinensis)

In the present study, bud yellow tea (BYT), small-leaf yellow tea (SYT) and large-leaf yellow tea (LYT) were produced from the same local “population” variety Huoshanjinjizhong (Camellia sinensis var. sinensis), and the effects of raw material tenderness on the chemical profile and bioactivities of these teas were investigated. The results showed that 11 crucial compounds were screened by headspace solid-phase microextraction-gas chromatography–mass spectrometry from 64 volatiles in these yellow teas, among which the heterocyclic compounds showed the greatest variations. In addition, 43 key compounds including organic acids, flavan-3-ols, amino acids, saccharides, glycosides and other compounds were screened by liquid chromatography-mass spectrometry from 1781 non-volatile compounds. BYT showed the best α-glucosidase inhibitory activity and antioxidant capacity among the selected yellow teas, which might be contributed by the higher content of galloylated catechins. These findings provided a better understanding of the chemical profile and bioactivities of yellow teas.

HS-SPME-GC-MS untargeted metabolomics reveals key volatile compound changes during Liupao tea fermentation

This study used headspace solid-phase microextraction-gas chromatography–mass spectrometry and multivariate statistical analysis to comprehensively analyze the volatile components in Liupao tea samples throughout fermentation. In total, 1009 volatile organic compounds were detected and identified, including terpenoids, heterocyclic compounds, esters, ketones, hydrocarbons, alcohols, aromatics, and acids. Principal component and hierarchical cluster analyses, characterize the volatile components of Liupao tea samples were characterized at various fermentation stages. Orthogonal partial least squares discriminant analysis identified 248 differentiating compounds (VIP ≥ 1, P < 0.05, and |Log2FC| ≥ 1.0) during fermentation. K-means clustering analysis showed that 11 metabolites increased significantly throughout the fermentation process, whereas 31 metabolites decreased continuously. Annotation of these differential compounds revealed significant changes in sensory flavor characteristics in “green, sweet, fruity, floral, and woody” flavors. The results demonstrated significant variations in the volatile components of Liupao tea fermentation, along with notable changes in flavor characteristics.

Comparison and identification of aroma components in 21 kinds of frankincense with variety and region based on the odor intensity characteristic spectrum constructed by HS–SPME–GC–MS combined with E-nose

Frankincense is an important seasoning and spice known for its distinctive and intricate flavor profile. Considering the considerable variation in the aromatic quality of frankincense due to geographical origin, species diversity and cultivation conditions, frankincense from major global origins was characterized holistically for the first time. The electronic nose (E-nose) with headspace solid-phase microextraction gas chromatography–mass spectrometry (HS–SPME–GC–MS) and sensory evaluation were implemented to characterize the aroma components of 21 commercial varieties of frankincense from around the world. The results showed that a total of 149 volatile organic compounds (VOCs) of 10 categories were identified in frankincense, among which the numbers of alcohols, terpenes and esters compounds accounted for 22.15 %, 18.79 % and 15.44 % of the total VOCs of frankincense, respectively. The PLS-DA model effectively distinguished frankincense from Oman/Somalia and other origins. Furthermore, the study identified two differential VOCs with VIP > 1 in three Asian countries and five in six African countries. The total VOCs content and sensory characteristic score of “Lemon/Citrus” in Oman frankincense is significantly higher than other regions. The OAV results showed that 61 substances (e.g., Diacety, alpha-Pinene, Camphene, Myrcene) as key aroma compounds and OICS model indicated that p-Cymenol was found to contribute significantly to the citrus aroma in frankincense. This study identified the fundamental components of frankincense flavor and revealed different flavor descriptors of frankincense, which are crucial for reconstructing frankincense flavor and improving flavor quality.

Effect of cooking methods on flavor profiles of Xuanwei Ham: Analytical insights into aromatic composition and sensory attributes

To examine flavor variations in Xuanwei ham due to different cooking methods, we selected one-year cured Xuanwei ham and applied four techniques: dry frying (DF), baking (BA), steaming (ST), and boiling (BO). Organoleptic evaluation revealed ST received the highest overall sensory score. High-performance liquid chromatography (HPLC) revealed that the total nucleotide content was significantly different (P < 0.05), lactic acid predominated the measured organic acids. Solid-phase microextraction-gas chromatography–mass spectrometry (SPME-GC–MS) and chromatography-electronic nose (GC-E-Nose) data indicated that ST resulting in significantly higher total volatile compounds than the other methods (P < 0.05). SPME-GC–MS detected 55 volatile compounds, and 12 characteristic flavor substances were identified using orthogonal partial least squares discriminant analysis (OPLS-DA) (VIP > 1). This study aimed to support comprehensive research on the flavor characteristics of cooked Xuanwei ham and guide the selection of appropriate processing methods.