Search Results (77)

Air-dried mutton is a traditional, culturally significant meat product, yet its spontaneous fermentation is inherently constrained by unstable microbial communities, leading to batch-to-batch quality inconsistency and potential food safety hazards. Elucidating whether composite starter cultures can modulate the microbiota and enhance product quality is therefore critical for standardized industrial processing. Herein, we investigated the effects of a defined starter culture (composed of Lactiplantibacillus plantarum and Pediococcus pentosaceus in a 2:1 ratio, with a total inoculum of 10⁸ CFU/g) on the quality and flavor of air-dried mutton, comparing inoculated samples (FJ) with naturally fermented controls (ZR). The fermentation was conducted at 30 °C and 95% relative humidity (RH) for 24 h, followed by air-drying at 4 °C for 21 d, with all assays performed in three biological and three technical replicates. Starter inoculation significantly reduced the pH, water activity (Aw), total volatile basic nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) values while improving sensory acceptability (p < 0.05). Amplicon sequencing analysis revealed a lactic acid bacteria (LAB)-dominated microbiota in FJ samples, with elevated abundances of Pediococcus and Lactobacillus and reduced abundance of Pseudomonas. The inoculated group also exhibited altered eicosapentaenoic acid content and a more diverse volatile flavor profile, with eight key aroma compounds positively correlating with LAB abundance. These findings demonstrate that composite starter inoculation improves physicochemical quality, stabilizes the microbial community, and enhances flavor in air-dried mutton. Further mechanistic validation and scale-up trials are required to confirm industrial applicability. Full article

Pigskin, a major byproduct of pork processing, has high protein content and low fat, endowing it with considerable market value for food applications. In this study, bioaugmented fermentation with Latilactobacillus sakei YBZY-W5, a strain previously isolated from traditional fermented pigskin, was applied to pigskin to systematically evaluate its effects on physicochemical parameters, microbial community succession, and volatile flavor compound (VFC) profiles over 20 days. The results showed that moisture and pH significantly decreased, while total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARSs) increased with fermentation time. High-throughput sequencing revealed that Lactobacilli, Fusarium and Aspergillus dominated early fermentation and were gradually replaced by Bacillus, Hanseniaspora and Debaryomyces. A total of 493 VFCs were identified, among which terpenoids, heterocyclic compounds, and alcohols were the most abundant classes. Orthogonal partial least squares discriminant analysis (OPLS-DA) identified numerous differentially changed VFCs (DCVFCs) during fermentation. Odor activity value (OAV) analysis indicated that green, meaty, and woody notes dominated initially, while sour, floral, sweet, and fruity characteristics became increasingly prominent after fermentation. Pearson correlation analysis demonstrated significant associations between key microorganisms (Lactobacilli, Bacillus, Hanseniaspora, Debaryomyces) and DCVFCs (e.g., β-myrcene, ethyl hexanoate, hexanoic acid, ethyl ester, pyrazines). Collectively, bioaugmented fermentation with Ltb. sakei YBZY-W5 effectively modulated the physicochemical and microbial profiles of pigskin, enriched desirable flavor compounds, and reduced unpleasant odor, confirming its feasibility for producing high-quality fermented pigskin products. This study provides an experimental basis for the value-added utilization of pigskin and promotes sustainable development of the pork industry. Full article

Yunnan traditional rose jam is made from fresh Rosa ‘Crimson Glory’ petals and brown sugar through natural fermentation and has been consumed by local people for years due to its characteristic floral aroma. The present study investigated the dynamics and correlations between the microbial communities and flavor quality during 98-day fermentation at ambient temperature (23.72 ± 1.26 °C). The total titratable acidity (0.20–0.29 g/100 g) and reducing sugars content (0.92–5.37 g/100 g) increased with fermentation, while the pH (4.30–5.47), total phenolics content (0.25–0.72 g/100 g), and total flavonoids content (0.13–0.32 g/100 g) decreased. High-throughput 16S rDNA and ITS sequencing revealed that Klebsiella, Zygosaccharomyces, Starmerella, and Podosphaera were the dominant microorganisms. Esters and terpenoids were the main flavor substances. Based on relative odor activity value evaluation, the relative levels of volatile compounds responsible for rose, sweet, and fruity odors increased during fermentation, while those responsible for a green character diminished. The physicochemical properties, especially the total titratable acidity and reducing sugars, as well as esters and terpenoids were positively related with Zygosaccharomyces. The present study systematically elucidated the correlation between microbial communities and flavor formation during fermentation of Yunnan traditional rose jam, providing key scientific basis for flavor-targeted regulation and standardized production of this traditional fermented food. Full article

Strong-flavor-type Baijiu, represented by Wuliangye—a renowned traditional Chinese alcoholic beverage brewed from five grains (sorghum, rice, glutinous rice, wheat, and corn)—is widely consumed and appreciated for its balanced taste and potential health benefits. While the volatile flavor compounds of Baijiu have been well studied, its bioactive components and their underlying mechanisms remain insufficiently explored. In this study, widely targeted metabolomics techniques were innovatively employed, and 2128 compounds were identified from 10 Wuliangye samples, of which 445 were predicted to constitute potential bioactive substances. Network pharmacology analysis further identified four key compounds, namely the four potential bioactive small molecules (fisetin, luteolin, norartocarpetin, and scutellarein), along with ten core targets that were key protein targets interacting with these compounds (SRC, PIK3R1, PTGS1, AKR1B1, STAT3, CYP3A4, ESR1, PIK3CA, PIK3CB, and ALOX15). GO and KEGG enrichment analyses indicated that these targets participated in diverse biological processes, while DO analysis revealed potential associations between these targets and specific diseases. Additionally, molecular docking confirmed the binding patterns between the identified compounds and their targets. Collectively, this study provides systematic chemical information and theoretical screening results for identifying potential bioactive components in strong-flavor-type Baijiu, which may facilitate further studies of their biological functions. Full article

Radish leaves are a nutrient-rich yet underutilized byproduct containing abundant fiber, minerals, and phytochemicals; however, their quality is highly affected by drying methods. This study systematically investigated the effects of three drying methods—hot-air drying (HD), microwave drying (MD), and freeze-vacuum drying (FD)—on the nutritional components, bioactive substances, and volatile compounds of radish leaves. A comparative analysis was conducted on their proximate composition, amino acid profiles, mineral contents, antioxidant capacities, glucosinolate profiles, and volatile profiles. Among the three methods, FD exhibited superior preservation of proteins, lipids, minerals (K, Mg, P, Fe, Zn, and Mn), and bioactive components, including polyphenols, flavonoids, glucosinolates, and vitamin C. In contrast, HD and MD led to significant reductions in these nutrients and bioactive compounds. A total of 33 glucosinolates and 779 volatile compounds, including 164 odor-active compounds, were identified collectively across the three treatments. The FD-treated samples exhibited distinct glucosinolate and volatile profiles, whereas HD- and MD-treated samples showed greater similarity. Multivariate analysis further revealed 12 key differential glucosinolates and 27 differential odor-active compounds among the three groups. This study provides a scientific basis for optimizing drying strategies to improve the nutritional quality and flavor characteristics of processed radish leaves. Full article

Microbial fermentation is an important means to enhance the nutrition and functionality of food, and soybean fermentation has a long history and a wide variety of products. This study systematically compared the effects of fermentation and post-ripening processes of Bacillus subtilis natto JLCC513 on the nutritional components, active substances, and sensory characteristics of soybeans. The experimental results showed that, in terms of basic nutrition, fermentation led to a significant decrease in fat and reducing sugar content, followed by an initial increase and then a decrease in total protein content. In contrast, water-soluble protein continued to increase, and the total amount of free amino acids surged. The active nutritional indicators before and after soybean fermentation showed that nattokinase activity continued to increase during fermentation and post-ripening. At the same time, the number of viable bacteria decreased slightly during post-ripening. The increase in the proportion of easily absorbed aglycone-type isoflavones before and after soybean fermentation is accompanied by a sustained increase in vitamin K2 and gamma aminobutyric acid (GABA) content. In terms of sensory quality, color-difference analysis shows a decrease in brightness (L value) and an increase in redness (a value), resulting in the characteristic yellow-brown color of natto. In terms of texture characteristics, the hardness decreases, while the viscosity and elasticity are significantly enhanced. Through GC-IMS analysis of volatile aromas during soybean fermentation and post-ripening, it was found that esters (such as ethyl acetate) and pyrazines (such as 2,3-dimethylpyrazine) increased, and the product flavor shifted from grassy to fruity and nutty. In summary, natto bacteria enhance the digestibility, nutritional value, and sensory acceptance of soybeans through enzymatic hydrolysis and metabolic transformation. The post-ripening stage plays a key role in flavor maturation and further accumulation of active ingredients. Full article

Daqu quality plays a crucial role in the entire fermentation process of Baijiu. There is no empirical evidence for a scientific consensus on the storage period of Jiang-flavor Daqu and its quality evaluation. This study took Jiang-flavor Daqu from a liquor enterprise in Sichuan Province as the research object. It explored the changes in physicochemical indexes, microbial communities, and volatile flavor substances of the Daqu within 0–180 days of storage. Combined with simulated brewing experiments, it analyzed the effects of different storage periods of Daqu on fermented grain fermentation and the base wine quality and clarified the metabolic differences between Daqu stored for 30 days and 180 days by means of metabolomics. The results showed that the saccharification power and fermentation power of Daqu first increased and then stabilized, reaching 205 mg/g·h and 0.71 g/g·72, respectively, at 180 days. The microbial diversity first increased and then decreased, with Virgibacillus and Oceanobacillus alternately serving as the dominant bacteria. The flavor substances were more abundant within 60 days of storage, while the content of pyrazine compounds was the highest at 180 days. The wine yield of Daqu stored for 30 days was 2.26 times that of Daqu stored for 180 days. The brewing stage had the greatest impact on metabolites, and flavonoid synthesis was the key metabolic pathway. This study provides theoretical support for the scientific storage of Jiang-flavor Daqu and the standardization of its quality. Full article

A systematic understanding of the overall flavor and taste characteristics across different white radish varieties is still lacking. This study selected six white radish varieties and analyzed their texture, taste, and flavor profiles. The results showed that JYHX had excellent hardness and chewiness, and CKJRM had the highest brittleness. The total sugar content of XY418 was the highest, and the sweetness was the most prominent. The umami and bitterness of CKXY and XY477 contributed significantly. A total of 43 volatile compounds were detected by gas chromatography–mass spectrometry (GC-MS), and CKFM12 had the highest content of sulfur-containing compounds. Dimethyl trisulfide and erucin were the key substances for the characteristic flavor of white radish. In this study, the texture, taste, and flavor characteristics of several white radish varieties and their potential biochemical components (cell wall substances, amino acids, volatile compounds) were comprehensively compared and analyzed for the first time. These findings provide a scientific basis for targeted quality evaluation, flavor improvement, and variety selection based on specific cooking applications and processing needs. Full article

Flavoromics and metabolomics were used to evaluate the effects of selenium-enriched yeast (SEY) in hen feed on the volatile flavor and nutritional quality indicators in the resulting chicken meats. Volatile organic compounds (VOCs) were analyzed using GC-MS and odor activity value calculations. Ninety-eight VOCs were identified. The treatment group had more abundant VOCs, with mainly increased fat, mushroom, fruit, and vanilla odor. Modulating the nutritional profile of chicken meat through SEY feed can reduce saturated fatty acid levels, increase unsaturated fatty acid levels, and significantly reduce cholesterol levels in Dongxiang green-shell chicken (DX). Metabolomics analysis has elucidated the potential mechanisms, whereby adding SEY to the diet of DX reduces cholesterol levels through secondary bile acid biosynthesis pathways. Its related metabolic changes may also directly or indirectly promote the formation of key substances that give meat its flavor. Adding SEY to the diet of Jingfen laying hens affects the muscle metabolism environment via the propanoate metabolism pathway, increasing the grassy notes of chicken meat while reducing its gamey taste. Full article

The quality, flavor, and functional attributes of fermented foods are intrinsically shaped by the composition and metabolic dynamics of their microbial communities. This systematic review explores the structural organization, successional patterns, and mechanistic roles of these communities in influencing food quality, with a specific focus on core functional groups—including lactic acid bacteria (LAB), yeasts, and molds—and their interplay through key metabolic pathways. By integrating multi-omics approaches, such as metagenomics and metabolomics, we elucidate the underlying relationships between microbial activity and the formation of volatile flavor compounds, nutritional metabolites, and bioactive substances. These insights offer a scientific basis for the targeted regulation and functional enhancement of fermented food products. Full article

This review examines the nutritional and functional potential of Acheta domesticus, the impact of fermentation on its biochemical and microbiological properties, and its application in food ingredients and products. Relevant literature was reviewed on the composition, fermentation behavior, product development, and consumer perceptions related to cricket-based ingredients, with a focus on fermented applications and microbiota interaction. Fermentation improves the safety, digestibility, flavor, and nutritional value of cricket powder. Lactic acid bacteria (e.g., Lactiplantibacillus plantarum and Latilactobacillus curvatus) enhanced substrate acidification, reduced biogenic amines and acrylamide levels, and contributed to desirable volatile compounds production. Additionally, fermentation using yeasts like Yarrowia lipolytica and Debaryomyces hansenii resulted in the production of antimicrobial substances, reduction in chitin, and an increase in the matrix digestibility. Fermented cricket-based ingredients have been successfully applied to bread, biscuits, yogurt, and beverages. Protein hydrolysates produced by fermentation exhibited antioxidant, anti-aging, and preservative properties, expanding potential beyond food. Consumer acceptance was highest when insects were integrated into familiar and visually unobtrusive food formats. To conclude, A. domesticus shows great promise as a sustainable and functional food ingredient. Fermentation offers a key strategy to overcome safety, sensory, and acceptability barriers. Full article

Three-Cup Chicken, a traditional Hakka dish, is known for its distinctive umami and salty flavor profile. However, the dynamic evolution of key flavor compounds and associated physicochemical attributes during its characteristic stewing process remains inadequately characterized. Therefore, this study investigated flavor and quality changes in Three-Cup Chicken during stewing using an integrated analytical approach, including gas chromatography-mass spectrometry (GC-MS), gas chromatography-ion mobility spectrometry (GC-IMS), E-tongue, and E-nose, alongside analyses of texture, color, pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid-reactive substances (TBARS), and moisture content. The results revealed that prolonged stewing promoted lipid oxidation, increased hardness, enhanced redness and yellowness, while moisture content gradually decreased. Electronic tongue and nose analyses revealed an increase in saltiness, umami, and sulfur compounds during stewing, complemented by a significant rise in umami amino acids from further analysis. Ten important taste compounds with variable importance in projection (VIP) > 1 and odour activity value (OAV) > 1 were filtered out of 137 volatile compounds, the majority of which were aldehydes. These research findings clearly demonstrate the formation and evolution patterns of the savory and salty flavor profile in Three-Cup Chicken, offering theoretical underpinnings as well as helpful advice for maximizing the dish’s genuine flavor. Full article

4-Chlorophenoxyacetic acid (4-CPA) is an auxin-type plant growth regulator widely used in fruit and vegetable production. However, its influence on the nutritional and sensory qualities of horticultural crops remains insufficiently characterized. This study investigated the influence of 4-CPA application and oscillator-mediated pollination on the metabolic composition of fully ripe fruits of Solanum lycopersicum var. cerasiforme cv. ‘Zheyingfen No. 1’. Two concentrations of 4-CPA (16 mg/L and 8 mg/L) were applied during flowering, and their effects on amino acids, soluble sugars, organic acids, and volatile compounds (VOCs) were comparatively analyzed. The results indicated that treatment with 8 mg/L 4-CPA treatment significantly increased the total amino acid content in ripe fruits compared with the control and the 16 mg/L treatment. Among the 17 amino acids identified, the contents of umami-related amino acids, including glutamic acid (Glu) and aspartic acid (Asp), were markedly enhanced. In particular, Glu content in the C8 treatment was the highest and accounted for more than 50% of the total amino acid content. The accumulation of sugars was not significantly affected by 4-CPA treatment, while the C8 treatment resulted in the lowest level of total organic acids, which are crucial for flavor development at the ripening stage. A 29.35% increase in VOCs was observed” for conciseness in 4-CPA-treated fruits compared with the control. Analysis of relative odor activity values (rOAVs) showed that although 4-CPA treatment reduced the number of aroma-active compounds, it promoted the accumulation of β-ionone, thereby shifting the tomato fruit aroma profile toward floral, woody, sweet, and fruity notes. In summary, 4-CPA treatment regulated the nutritional and flavor quality of ripe cherry tomato fruits by increasing the content of Glu and other amino acids, enhancing the diversity of VOCs, and promoting the formation of key aroma-active substances such as β-ionone. Full article

The contents of secondary metabolites such as tea polyphenols, amino acids, caffeine, and volatile metabolites in fresh tea leaves are key factors determining the unique flavor and health attributes of finished tea products. However, differences in varieties, cultivation practices, and environmental conditions often lead to variations in these metabolites among fresh tea leaves, thereby affecting tea quality. In order to clarify the various internal and external factors that influence the formation of the quality of fresh tea leaves and their mechanism of action. This article mainly reviews the research on fresh leaf quality in the past decade. Firstly, it clarifies the molecular basis of metabolic differences among varieties. Then, it summarizes the regulatory mechanisms of underground (soil, microorganisms) and above-ground (light, temperature, humidity) environments on key metabolic pathways, and focuses on evaluating the effects of intercropping, fertilization, and other cultivation measures on improving tea quality. This review found that the specific gene expression of varieties, the transmission of environmental signals, and cultivation interventions jointly drive the synthesis and accumulation of tea polyphenols, amino acids, caffeine, and aroma substances. However, no one has ever systematically reviewed it. Therefore, it provides certain theoretical references for improving the quality of fresh leaves. Full article

This study aimed to investigate the effect of thermal sterilization on the volatile flavor of sauced duck necks. The study revealed that thermal sterilization significantly reduced the content of unsaturated fatty acids (e.g., oleic acid C18:1n9c) in sauced duck necks. This was accompanied by elevated thiobarbituric acid reactive substances (max 0.86 mg/100 g) and peroxide values (max 1.13 g/100 g), indicating intensified lipid oxidation. Through PLS-DA, six key differential free fatty acids distinguishing the sterilization treatment groups were identified: cis-9-tetradecadecarbonate, methyl tridecarbonate, cis-10-17-cetenoic acid, antioleic acid, cis-13-docosaenoic acid methyl ester, and lauric acid. The primary volatile flavor compounds in sauced duck necks were identified as alkenes and ethers. Post-sterilization alterations in volatile flavor profiles primarily resulted from compositional changes in alkenes, esters, and ethers within the total volatile compounds. Moreover, it was demonstrated that sterilization temperature exerted a significantly greater impact on the quality of sauced duck necks than sterilization duration. Following organoleptic evaluation, samples subjected to low-temperature prolonged sterilization (90 °C for 30 min) exhibited the highest aroma scores, establishing this protocol as the optimal thermal sterilization condition. This study is of great significance for selecting thermal sterilization conditions and maintaining meat flavor. Full article