Search Results (204)

‘Qiancha 1’ is an excellent raw material for manufacturing white tea. The effects of different drying parameters on the quality performance of ‘Qiancha 1’ white tea remain poorly understood, which restricts the precise regulation of the quality of ‘Qiancha 1’ white tea. In this research, we systematically investigated the influence of drying temperature (65 °C, 75 °C, and 90 °C) and drying duration (1 h, 2 h, and 3 h) on its non-volatile and volatile compositions, using sensory evaluation, E-tongue, and non-volatilomic and volatilomic analyses. The results showed that the tea sample dried at 65 °C for 3 h had a sweet, mellow, and fresh flavor and scored 95 points, but high-temperature drying (90 °C) could promote increased bitterness and decreased sweetness. High-temperature drying was closely related to a caramel-like and milk-like flavor, which promoted an increase in the content of terpenoids, heterocycle compounds, and esters. During drying, the flavonoid and phenolic acid content increased markedly, contributing to bitterness and astringency, while nucleotides, amino acids, and their derivatives decreased, leading to a reduced umami intensity. A total of 37 key taste-active metabolites were identified, including bitter compounds (e.g., alkaloids), sweet compounds (e.g., phenolic acids), and umami compounds (e.g., nucleotides), whose dynamic changes directly influenced the taste profile of white tea. High-temperature drying promoted an increase in the content of volatile metabolites, such as terpenoids, heterocyclics, and esters, while low-temperature and long-duration drying was beneficial for preserving volatile metabolites like heptanal. 2-Methoxy-3-(1-methylethyl)-pyrazine was determined as the volatile compound with the highest rOAV, providing a sweetness and caramel-like flavor. Overall, the metabolomic analysis revealed that the content of flavonoids and phenolic acids increased after the drying process, which was related to the bitter and astringent taste of the tea liquor. The content of nucleotides, amino acids, and their derivatives decreased after drying, which caused the umami of the tea liquor to weaken. This study provides a theoretical basis for the optimization of the ‘Qiancha 1’ white tea drying process. Full article

Currently, there is little scientific data to support the importance of selecting non-Saccharomyces yeasts from different wineries in the Protected Designation of Origin (PDO) in Andalusia, southern Spain, and how this group of yeasts can affect the sensory properties of wine. Therefore, this research aimed to study some specific microbiological properties and the metabolites they could produce in order to evaluate the oenological potential of two non-Saccharomyces yeast strains isolated from a region of Andalusia (Córdoba, Spain), Hanseniaspora uvarum TJ-27 and Lachancea thermotolerans T-9, isolated from musts with high sugar content. Of 80 yeast isolates selected, these two strains were chosen for their notable β-glucosidase activity (observed in up to 40% of isolates), cellulase activity (present in 24%), and killer phenotype (found in 40%). In this study, strains that displayed characteristics associated with aroma release were selected. Fermentation assays using a high-sugar synthetic medium revealed that neither H. uvarum TJ-27 nor L. thermotolerans T-9 was able to complete alcoholic fermentation independently, achieving ethanol yields of only 5–6% v/v, indicating the need for subsequent fermentation by Saccharomyces cerevisiae. The originality of this study provides insight into the metabolites contributed by these strains to the wines produced. The best results were obtained when both strains were inoculated together. Furthermore, volatilome analysis showed elevated levels of key compounds such as isoamyl alcohols and 2,3-butanediol. These findings highlight the practical potential of using selected non-Saccharomyces strains from Andalusia to improve fermentation results and wine quality. The novelty of this study lies mainly in confirmation within region-specific isolates. Full article

Volatile organic compounds (VOCs) play critical roles in broccoli’s sensory attributes, defense mechanisms, and ecological interactions, yet comprehensive profiling of its volatilome remains limited. This study aimed to construct a robust and inclusive volatile metabolite database for broccoli using advanced analytical techniques. A pooled sample comprising florets from 191 cultivars was prepared to capture broad chemical diversity and analyzed using solid-phase microextraction–gas chromatography–high-resolution mass spectrometry (SPME-GC-HRMS) under dual ionization modes: electron ionization (EI) and chemical ionization (CI). A total of 206 VOCs spanning nine chemical classes were detected, with 37 compounds further confirmed through synchronized CI analysis. To validate the database, broccoli florets from seven distinct cultivars were analyzed using the same workflow. Of the 206 compounds, 187 (90.78%) were detected in at least one cultivar, while 38 were consistently found across all samples, indicating a conserved core volatilome. Principal component analysis revealed distinct VOC profiles among cultivars, and freeze-dried samples were found suitable for reproducible large-scale analysis. This study demonstrates that a pooled-sample strategy coupled with dual-ionization GC-HRMS provides comprehensive and reliable VOC coverage. The resulting database offers a valuable resource for metabolomics studies in Brassica, with applications in cultivar differentiation, flavor research, and environmental response profiling. Full article

The present study provided an exhaustive examination of VOC emissions originating from 13 different raw materials susceptible to being used in the sampling of the human volatilome and encompassing both polymeric and non-polymeric compositions. To achieve this aim, thermodesorption coupled with comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (TD-GC×GC/ToFMS) was employed. For each material, we report the total number of detected peaks, total volatile organic compound (TVOC) concentration, distribution of VOC emissions across different chemical families, minimum and maximum individual concentrations, as well as hypotheses regarding the origins of some specific VOCs depending on the material considered. The findings from this investigation revealed that materials, such as silicone and polyurethane, could emit an extensive array of VOCs, with up to 2000 chromatographic peaks detected, and emissions of total volatile organic compounds (TVOCs) reaching levels of 5.4 µg·g⁻¹ and 9.8 µg·g⁻¹, respectively. In the case of polyamide, some VOCs could be related to potential reagents involved in its synthesis. While highlighting materials that should be used with caution depending on the topic and target analytes, this study identified materials that exhibited minimal VOC emissions, such as polytetrafluoroethylene, aluminum, and stainless steel, after an adequate conditioning step. The selected analytical technique, TD-GC×GC/ToFMS, proved its relevance to identify and characterize semi-quantitatively VOC emissions coming from those materials. Such information was essential within the frame of the development of a body odor sampling system, our primary objective. Full article

Background: Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide, emphasizing the urgent need for early, non-invasive, and accessible diagnostic tools. This study aimed to evaluate the effectiveness of a microelectromechanical systems (MEMS)-based electronic nose (E-nose) in combination with gas chromatography–mass spectrometry (GC-MS) for CRC detection through sweat volatile organic compounds (VOCs). Methods: A total of 136 sweat samples were collected from 68 volunteer participants. Samples were processed using solid-phase microextraction (SPME) and analyzed by GC-MS, while a custom-designed E-nose system comprising 14 gas sensors captured real-time VOC profiles. Data were analyzed using multivariate statistical techniques, including PCA and PLS-DA, and classified with machine learning algorithms (LDA, LR, SVM, k-NN). Results: GC-MS analysis revealed statistically significant differences between CRC patients and healthy controls (COs). Cross-validation showed that the highest classification accuracy for GC-MS data was 81% with the k-NN classifier, whereas E-nose data achieved up to 97% accuracy using the LDA classifier. Conclusions: Sweat volatilome analysis, supported by advanced data processing and complementary use of E-nose technology and GC-MS, demonstrates strong potential as a reliable, non-invasive approach for early CRC detection. Full article

Volatilomic and sensory analyses of wine are excellent tools for enologists and winemakers when selecting commercial yeast based on the production of metabolites related to desirable wine characteristics. Integrating this holistic approach could lead to the terroir description, characterization, and quality control improvement of the vinification process. Volatilomic and sensory profiles of Cabernet Sauvignon Mexican wines fermented with three commercial yeasts (WLP740, ICVD254, and ICVD80) were obtained using HS-SPME-GC-qTOF/MS and CATA evaluation. A total of 100 volatile compounds were identified, with unique entities per strain. WLP740 wines were rated as high quality, presenting fruity and minty aromas with fewer off-aromas, while ICVD254 wines showed higher levels of compounds associated with off-notes and were rated as low quality. ICVD80 wines were of medium quality, with fruity esters and higher alcohols descriptors. Volatilomic profiles highlighted the role of specific compounds in differentiating strains and sensory attributes, while yeast selection significantly impacts wine aroma and quality. The authors acknowledge the need for further analyses, including an increased sample size, yeast species, diverse vineyards, and vinification processes, which will result in a solid and robust methodology. Full article

Nuts are nutrient-dense foods recognized for their complex chemical composition and associated health benefits. This review provides a comprehensive overview of the botanical classification, morphology, production, and consumption patterns of key nut species, including walnuts, almonds, pistachios, pecans, peanuts, cashews, bitter kola, and kola nuts. It emphasizes the fatty acid profiles, noting that palmitic acid (C16:0) is the predominant saturated fatty acid, while oleic acid (C18:1) and linoleic acid (C18:2) are the most abundant monounsaturated and polyunsaturated fatty acids, respectively. The review also details various analytical techniques employed for extracting and characterizing bioactive compounds, which are crucial for assessing nut quality and health benefits. Methods such as Soxhlet extraction, solid-phase microextraction (SPME), supercritical fluid extraction (SFE), gas chromatography (GC-FID and GC-MS), and high-performance liquid chromatography (HPLC) are highlighted. Furthermore, it discusses scientific evidence linking nut consumption to antioxidant and anti-inflammatory properties, improved cardiovascular health, and a reduced risk of type 2 diabetes, establishing nuts as important components in a healthy diet. This review underscores the role of nuts as functional foods and calls for standardized methodologies in future lipidomic and volatilomic studies. Full article

Tomatoes are globally esteemed not only for their nutritional value but also for their complex and appealing aroma, a key determinant of consumer preference. The present study aimed to comprehensively characterise the volatilomic fingerprints of three tomato species—Solanum lycopersicum L., S. lycopersicum var. cerasiforme, and S. betaceum—encompassing six distinct varieties, through the application of headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS). A total of 55 volatile organic compounds (VOCs) spanning multiple chemical classes were identified, of which only 28 were ubiquitously present across all varieties examined. Carbonyl compounds constituted the predominant chemical family, with hexanal and (E)-2-hexenal emerging as putative key contributors to the characteristic green and fresh olfactory notes. Notably, esters were found to dominate the unique volatile fingerprint of cherry tomatoes, particularly methyl 2-hydroxybenzoate, while Kumato and Roma varieties exhibited elevated levels of furanic compounds. Multivariate statistical analyses, including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), demonstrated clear varietal discrimination and identified potential aroma-associated biomarkers such as phenylethyl alcohol, 3-methyl-1-butanol, hexanal, (E)-2-octenal, (E)-2-nonenal, and heptanal. Collectively, these findings underscore the utility of volatilomic fingerprint as a robust tool for varietal identification and quality control within the food industry. Full article

Dates (Phoenix dactylifera L.) are nutrient-rich fruits with health-promoting properties and broad applications in the food and beverage industries. This study analyzes the chemical properties and volatile profile of fermented date products—juice, alcoholic derivative, and vinegar—to develop a high-quality vinegar with distinct sensory traits. Using HS-SPME-GC-MS, about 50 volatile compounds were identified across six major chemical classes. Juice processing significantly increased volatile release, especially fusel alcohols and furanic aldehydes, due to thermal and mechanical disruption. Fermentation further modified the volatilome, with increased esters and acids in alcoholic and vinegar products. Vinegar was characterized by high levels of acetic acid, fatty acids, phenols, and acetoin (855 mg/L), indicating active microbial metabolism. Ethanol and acidity levels met international standards. Total phenolic content rose from juice (138 mg/L) to vinegar (181 mg/L), reflecting microbial enzymatic activity and acid-driven extraction. These results highlight the metabolic complexity, sensory richness, and functional potential of date-derived fermented products while promoting sustainable use of underutilized fruit resources. Full article

This study investigated young white wines produced during the 2021 and 2022 vintages from Pedro Ximénez grapes cultivated in three different terroirs within a high-quality production zone. The general oenological parameters were significantly influenced by vintage and terroir (p ≤ 0.001), with ethanol and reducing sugars specifically affected by the terroir and its interaction with the vintage. Multivariate analysis of major and minor volatile compounds enabled the characterization of terroir-specific volatile profiles. However, principal component analysis (PCA) grouped samples by vintage rather than terroir. Ethyl esters of medium- and long-chain fatty acids and certain acetates of higher alcohols were the most discriminant volatiles and were proposed as key compounds for differentiating wines by terroir and vintage. These findings underscore the influence of the terroir on the volatilome and support its relevance in defining wine typicity and quality. Full article

Honey is a natural product produced by bees from the nectar of plants and has been widely used as a sweetener for centuries. In addition to its traditional use, it is also employed for other purposes due to its biological and nutraceutical properties. Although honey production is mostly associated with bees of the genus Apis, species from other genera, such as Melipona, also produce it, albeit on a smaller scale. The honey produced by these two genera shows significant differences in its composition. Moreover, distinct geographical localizations, which, consequently, have different flora, guide the chemical compositions of these samples. Regarding the Amazon region, the amount of knowledge about the honey samples from Melipona species is still scarce. In this context, the present study aimed to characterize the volatile compositions of honey from Melipona interrupta and Melipona seminigra, as well as from the floral sources available, in addition to evaluating their nutritional aspects, antioxidant activity, and antibacterial activity. The analysis of chemical composition was performed using gas chromatography coupled to mass spectrometry (GC-MS). Antioxidant activity was determined by DPPH and ABTS assays, while antimicrobial activity was tested against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus epidermidis, Enterococcus faecalis, Salmonella enterica, Serratia marcescens, Bacillus subtilis, Candida albicans, Candida tropicalis, and Candida parapsilosis. The results allowed the identification of volatiles present in the honey and floral sources. The samples displayed moderate antioxidant activity and slightly antibacterial activity (MIC) of 75 μg/mL against two bacterial strains tested, demonstrating potential antimicrobial activity. Full article

The garden Nasturtium (Tropaeolum majus L.) is increasingly consumed worldwide due to its culinary appeal and perceived health benefits. However, the chemical markers underlying its functional properties remain insufficiently characterized. Building on evidence from a recent human pilot study confirming both high acceptability and dietary safety, we conducted a comprehensive volatilomic and phytochemical analysis of T. majus flowers and their juice. Headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS) was employed to establish the volatilomic fingerprint of floral tissues and juice. Our analysis revealed a striking dominance of benzyl isothiocyanate and benzonitrile, which together accounted for 88% of the total volatile organic metabolites (VOMs) in the juice, 67% and 21%, respectively. In the floral tissues, benzyl isothiocyanate was even more prevalent, representing 95% of the total volatile profile. Complementary in vitro assays confirmed a substantial total phenolic content and strong antioxidant activity in the flowers. These findings provide a robust chemical rationale for the potential health-promoting attributes of T. majus, while identifying key volatilomic markers that could support future functional and safety claims. In parallel, a benefit–risk assessment framework is discussed in accordance with the European Food Safety Authority (EFSA) guidelines for the Qualified Presumption of Safety (QPS) of edible flowers. Given that both benzyl isothiocyanate and benzonitrile are classified as Cramer Class III substances, a conservative intake threshold of 1.5 μg/kg body weight per day is proposed. To enable quantitative exposure modeling and support the derivation of a tolerable daily intake (TDI), future studies should integrate organic solvent-based extraction methodologies to estimate the total volatile load per gram of floral biomass. This would align risk–benefit assessments with the EFSA’s evolving framework for novel foods and functional ingredients. Full article

Liangshan Semi-fine Wool Sheep (LSWS, Ovis aries) are widely raised in Liangshan Yi Autonomous Prefecture, Sichuan, China. To provide a scientific basis for LSWS meat processing, our study investigated various parameters across six meat parts of LSWS including the neck, chuck roll, thin flank, outside flat, eye of round, and hind shank. Our findings revealed that thin flank displayed a higher pH₂₄ compared to outside flat (p < 0.05), as well as greater lightness than outside flat and hind shank (p < 0.05), along with higher redness than eye of round (p < 0.05). Hardness among six meat parts ranked in descending order as chuck roll, hind shank, outside flat, eye of round, neck, and thin flank. Meanwhile, the odor activity value decreased in the order of thin flank, eye of round, hind shank, neck, chuck roll, and outside flat. In terms of the nutritional composition, hind shank exhibited the highest protein content (p < 0.05). Thin flank also contained elevated levels of polyunsaturated fatty acids (PUFAs, 4977 μg/g), Σn-3 (1859 μg/g) and Σn-6 (2962 μg/g) fatty acids (p < 0.05). Regarding human health implications, thin flank showed a lower thrombogenicity index (p < 0.05). This study undertook a comprehensive analysis of meat quality and nutritional attributes across six LSWS meat parts, providing a scientific foundation for LSWS meat industry development and assisting consumers in making informed purchasing decisions. Full article

A traditional dairy product from northern Colombia is suero costeño (SC), typically handmade through artisanal processes involving the natural fermentation of raw cow’s milk (RM); it is characterized by a creamy texture and a distinctive sensory profile, with a sour/salty taste and rancid odor. This study aimed to determine the chemical identity (using GC-FID/MSD) of SC and RM samples (from eight locations in the department of Córdoba-Colombia) by analyzing volatile components (trapped by HS-SPME and SDE) and fatty acid content. Consequently, the most notable results were as follows: (a) myristic (7–12%), stearic (12–17%), oleic (13–23%), and palmitic (21–29%) acids were the most abundant constituents [without significant differences among them (p > 0.05)] in both RM and SC fats; these were also expressed as polyunsaturated (2–5%), monounsaturated (26–36%), saturated (59–69%), omega-9 (19–30%), omega-6 (0.5–1.6%), and omega-3 (0.2–1.2%) fatty acids; (b) differences in the composition (p < 0.05) of the volatile fractions were distinguished between RM and SC samples; likewise, the SC samples differed (from each other) in their volatile composition due to the preparation processes applied (processes with raw milk and natural fermentation had less variability); nonetheless, it was possible to determine the volatilome for the artisanal product; and (c) the major components responsible for the chemical identity of SC were ethyl esters (of linear saturated and unsaturated acids, short/medium chains), aliphatic alcohols (linear/branched, short/long chains), aliphatic aldehydes (long chains, >C₁₄), alkyl methyl ketones (long chains, >C₁₁), sesquiterpenes (caryophyllane/humulane types), monoterpenes (mono/bi-cyclics), short-chain fatty acids, and aromatic alcohol/acid, among others. Full article

Previous studies have shown the positive effects of non-conventional Metschnikowia spp. yeasts in mixed cultures with Saccharomyces cerevisiae on the properties of fruit wines. In this study, we investigated the effects of using conventional S. cerevisiae and non-conventional Metschnikowia pulcherrima yeasts as starter cultures in controlled mixed fermentations of honey wort. Other non-conventional yeasts were also tested for comparison, including Wickerhamomyces anomalus, Dekkera/Bretannomyces bruxellensis, and Wickerhamomyces anomalus. We evaluated the tolerance of the tested yeasts to high sugar content and analyzed the metabolic profiles of both monocultures and mixed systems. The M. pulcherrima strain showed the highest tolerance to 30% w/v glucose. The chemical complexity of fermented honey was improved using M. pulcherrima in co-starters with S. cerevisiae. The fermented honey samples were characterized by lower ethanol content, higher glycerol level, and rich volatilomes containing higher levels of both esters (ethyl acetate, 3-methylbutyl acetate, 2-methylpropyl acetate) and aliphatic alcohols (2-methylpropan-1-ol, 3-methylbutan-1-ol, and 2-methylbutan-1-ol). Similar characteristics were obtained using mixed populations of four strains: S. cerevisiae, M. pulcherrima, D. bruxellensis, and W. anomalus. Full article