Flavor Quality Research Articles

Effect of Ganoderma lucidum water extract on flavor volatiles and quality characteristics of set-type yogurt

This study investigated the effects of several concentrations of Ganoderma lucidum water extract (GLWE) (0, 0.5, 1.0, and 1.5 %) on set-type yogurt's flavor volatiles as well as the physicochemical, textural, and antioxidant activities of the yogurt during storage. The HS-SPME-GC–MS investigation found that adding GLWE increased the amount of flavor volatiles in yogurt, which improved the quality of flavor volatiles produced by the yogurt. The yogurt's water holding capacity, syneresis, color, and texture all showed optimum values at a 0.5 % GLWE concentration, and its total number of flavor volatiles reached 43. To sum up, the incorporation of GLWE at a 0.5 % concentration promotes the development of superior flavor volatiles in yogurt and enhances its qualitative attributes in contrast to the control group.

Metabolomics reveals a differential attitude in phytochemical profile of black tea (Camellia Sinensis Var. assamica) during processing

Black tea's quality and flavor are largely influenced by its processing stages, which affect its volatile and non-volatile phytochemicals. This study aimed to optimized black tea manufacturing by investigating withering time, fermentation time, and temperature's impact on sensory quality. Using a U*15 (157) uniform design, optimal conditions were determined: 14 h of withering, 5.6 h of fermentation, and a 34 °C temperature. A verification experiment analyzed the volatile and non-volatile profiles. HPLC, GC–MS, and LC-MS revealed dynamic changes in phytochemicals. Among 157 VOCs and 2642 metabolites, 19 VOCs (VIP > 1.5) were crucial for aroma, while 50 (VIP > 1.5, p < 0.01) characteristic metabolites were identified. During processing, fragrant volatile compounds like linalool oxides, geraniol, benzeneacetaldehyde, benzaldehyde, methyl salicylate, and linalyl acetate increased, contributing to rose and honey like aromas. These changes were crucial in developing the characteristic flavor and color of black tea. Twenty-four new compounds formed, while 80 grassy odor volatiles decreased. Non-volatile metabolites changed notably, with decreased catechins and increased gallic acid. Theaflavin compounds rose initially but declined later. This study outlines metabolite changes in Yunkang 10 black tea, crucial for flavor enhancement and quality control.

High-pressure processing for pickled crabs: Safety, quality and flavor assessment and correlation analysis of spoilage indicators

Pickled aquatic products are often susceptible to spoilage, which can significantly affect their edibility and flavor. This study aimed to improve the safety and quality aspects of pickled crabs by treated with high-pressure processing (HPP, 400 MPa for 5 min). The physical, chemical, microbiological, and flavor properties of the crabs before and after HPP were assessed, correlation and cluster analysis and orthogonal partial least squares discriminant analysis (OPLS-DA) were conducted on specific indicators influencing crab spoilage. The results indicated that HPP effectively reduced the total viable count, psychrophilic bacteria count (PBC), and Escherichia coliform (E. coli) count during storage at 4 °C (reduced by 30.61%, 36.72%, 100%, day 0, respectively; 19.02%, 21.95%, 100%, day 42, respectively). Moreover, HPP treatment reduced the total volatile basic nitrogen (TVBN) content (35.33 mg/100 g to 31.81 mg/100 g) and the production of putrescine (1858.7 mg/kg to 1293.04 mg/kg) and cadaverine (753.47 mg/kg to 422.08 mg/kg) in the end of storage stage, which extend the shelf life of the pickled crab by 12 days. Furthermore, the application of HPP facilitated the penetration of ethanol into the crab meat, thereby enhancing the development of the characteristic pickled crab flavor. The OPLS-DA analyses indicated that TVBN, TBA, and histamine as deteriorative factors for quality deterioration are key factors determining spoilage of crab, which are significantly correlated with other corruption products. This study provides valuable insights into improving the safety and flavor of crab products, establishing a theoretical basis for ensuring quality control throughout the production process.

4D-FastDIA-based quantitative proteomics reveals protein biomarkers linked to flavor traits between triploid and diploid oysters (Crassostrea angulata)

In this study, the 4D-FastDIA-based quantitative proteomics strategy was employed to identify protein biomarkers linked to flavor traits in triploid and diploid oysters (Crassostrea angulata). A comprehensive analysis identified a total of 61,947 peptides and 9,703 protein groups across four sample groups, with 3,679 common proteins shared among all groups. Differentially expressed proteins (DEPs) were found to be significantly associated with flavor-related traits, revealing notable differences in amino acids, lipids, and nucleotides between triploid and diploid oysters. Enrichment analysis further elucidated significant pathways involved in metabolic processes, biosynthesis, and immune responses. Among the DEPs, 864 were correlated with flavor quality traits, highlighting key proteins such as S-adenosylmethionine synthase and pyruvate kinase as potential biomarkers for flavor traits. These findings provide valuable insights into the molecular mechanisms underlying flavor differences in oysters and offer potential biomarkers for evaluating and enhancing oyster quality.

Improvement of brown yogurt quality by Lactiplantibacillus plantarum S58 and oat β-glucan: Physicochemical properties, sensory quality, and metabolic changes

The flavor quality of brown yogurt is affected by the different fermentation methods. In this study, we investigated the effects of probiotics (Lactiplantibacillus plantarum S58), prebiotics (oat β-glucan), and synbiotics (Lactiplantibacillus plantarum S58 combined with oat β-glucan) on physicochemical properties, consumer acceptance, flavor substances, and metabolites of brown yogurt. The results showed that the addition of probiotics and synbiotics significantly shortened the curdling time of brown yogurt (30 min and 40 min, respectively), and synbiotics improved the physicochemical properties and flavor components of the yogurt. Compared with the control group, the volatile flavor substances in the synbiotic yogurt, such as acetophenone, 2-decanone, and octanoic acid, were significantly increased. Sensory analysis of 111 consumers showed that the sample of synbiotic brown yogurt was highly accepted and close to the ideal point. Synbiotic fermentation alters the metabolic profile of yogurt, increasing the levels of beneficial metabolites and reducing harmful metabolites. In conclusion, synbiotic brown yogurt achieved the highest quality. This study provides a theoretical basis and data support for the development of brown yogurt with high probiotic activity and a unique flavor.

Enhancing the flavor quality of Chinese rice wine (Huangjiu) through inoculation with Lactobacillus plantarum and Leuconostoc mesenteroides

This study investigates the modulation of flavor in Chinese rice wine (Huangjiu) by inoculating with Lactobacillus plantarum (L. plantarum) and Leuconostoc mesenteroides (L. mesenteroides). Firmicutes and lactic acid bacteria (LAB) were predominant in both inoculated and spontaneously fermented samples. We observed an enhanced bacterial diversity in treatments involving single and combined inoculations, which corresponded with increases in volatile components, organic acids, and amino acids compared to spontaneously fermented controls. Sensory evaluations, assessing alcohol aroma, sourness, and full-bodiedness, identified the co-inoculated samples as superior, outperforming those from single inoculations and spontaneous fermentations. These results elucidate the impact of starter cultures on the fermentation process and flavor profile of Huangjiu, providing insights for selecting optimal starters to engineer desired flavor characteristics.

Effect of ultrasound-assisted Maillard reaction on functional properties and flavor characteristics of Oyster protein enzymatic hydrolysates

To address the delamination phenomenon during storage and flavor characteristics of Oyster protein hydrolysates (OPH). In this study, xylo-oligosaccharides (XOS) were selected to covalently graft with OPH through ultrasound-assisted Maillard reaction, and the effect of ultrasound-assisted Maillard reaction on the structure, functional properties, and flavor characteristics of OPH were investigated. The results revealed that the ultrasound treatment led to a 1.46-fold increase in the degree of grafting compared with the conventional wet-heat Maillard reaction methods. Structural analyses at various levels indicated substantial alterations in the OPH structure following the ultrasound-assisted Maillard reaction. More ordered α-helical secondary structures were shifting to random coiling, the tertiary structure showed more stretching changes, and the surface structure was characterized by loose and porous features. Compared with OPH, the solubility of the ultrasound-assisted Maillard reaction products (OPH-U-M) increased from 54.67% to 70.14%, leading to a notable enhancement in storage stability. Flavor profile analysis demonstrated a decrease in unsaturated aldehydes and ketones presenting fishy and bitter aromas, while an increase in presenting meat aroma compounds was observed in OPH-U-M. Furthermore, OPH-U-M exhibited superior antioxidant properties with DPPH and ABTS radical scavenging abilities enhancing 46.05% and 42.09% in comparison with OPH, respectively. The results demonstrated that covalently binding with XOS under ultrasonication pretreatment endowed OPH with superior functional properties (including solubility, storage stability, and antioxidant activity), and the improvement of flavor profile. This study can provide theoretical guidance and practical implications for promoting the processing applications of oyster protein.

Bacterial community succession and its correlation with the dynamics of flavor compound during processing of Enshi bacon

Enshi bacon, a famous specialty in Enshi Prefecture, Hu Bei, China, is renowned among customers for the nutritious content and distinct smoky flavor. This study explored the flavor and bacterial flora changes of Enshi bacon during processing and investigated the effect of bacteria on flavor formation. The results showed that the main genera in the pre-processing stage were Brochothrix, Lactococcus and Psychrobacter, which originated from raw meat. Salt-tolerant Staphylococcus and Cobetia were the dominant genera in the late stage of processing. Five free amino acids (aspartic acid, glutamic, alanine, valine, and lysine) were recognized as the flavor substances promoting taste, while aldehydes and phenols were the volatiles that contributed the most to odor. Particularly, compared to the smoking phase, phenolic content increased 2.25-fold at the end of fermentation through microbial action and tyrosine catabolism. The correlation study showed Staphylococcus and Lactococcus as fundamental functional genera that are essential for the formation of bacon flavor. This study provided reference data for the changes in flavor indicators and flora during the processing of Enshi Bacon, revealed the potential mechanism of core functional flora and characteristic flavor formation, and provided a theoretical basis for quality control of the manufacturing process.

Analysis of the effect of fermentation duration on the organoleptic properties of dried cocoa beans (Theobroma cacao L.) at Nglanggeran Agricultural Technology Park

The post-harvest process of cocoa fruits includes fruit harvesting, cracking, wet bean sorting, fermentation, drying, dry bean sorting, and packaging. One of the post-harvest processes that significantly affects the quality of cocoa beans is fermentation. The fermentation process, facilitated by acetic acid and lactic acid bacteria, aims to reduce moisture content, enhance aroma and flavor, and improve the quality of cocoa beans. Acetic acid bacteria, such as Acetobacter and Gluconobacter, contribute to acetic acid production, giving cocoa beans their characteristic flavor. These bacteria convert alcohol into acetic acid, a process crucial for developing the beans' flavor. On the other hand, lactic acid bacteria, like Lactobacillus and Pediococcus, play a role in the breakdown of complex compounds, enhancing the aroma. These bacteria produce lactic acid, which contributes to the beans' aroma. One factor that influences the success of cocoa fruit fermentation is the duration of fermentation. The optimal fermentation time for cocoa fruits is 5 – 6 days. If it is less or exceeds the optimal time, the fermentation of cocoa fruits will not be perfect. The duration of cocoa fruit fermentation has been proven to affect the aroma, taste, texture, and color of dried cocoa beans. Keywords: Cocoa, Fermentation, Post-harvest process of cocoa, Organoleptic

Special Issue: ‘Advanced Studies in Maintaining Post-Harvest Quality of Fruits and Vegetables’

The characteristics of taste, flavor, nutrition, and safety in fruits and vegetables during post-harvest, minimal processing, fresh-cutting, fermenting, and processing are critical elements in the storage and sale of products [...]

Changes in flavor profile of vegetable seasonings by innovative drying technologies: A review.

Seasonings like garlic, ginger, and scallion provide spicy and masking flavor or aroma in vegetables. However, the method or technique used for drying these spices can affect the flavor profile. Therefore, this review focuses on vegetable seasonings like ginger, garlic, and scallion, the characteristic flavor of fresh and dehydrated vegetable seasoning, and how drying methods (freeze-drying [FD], convective hot air drying [HAD], infrared drying, microwave drying [MW]), and other recent dryers (swirling fluidized bed [SFB], pulsed-vacuum dryer, relative humidity-convective dryer, etc.) affect the flavor profile of the common vegetable seasonings. HAD increases α-zingiberene, reduces gingerol, and forms β-citral and citral in fresh ginger. FD increased sesquiterpenes, retained terpenoids, sulfides, and other volatiles in fresh ginger, and did not produce new volatile compounds (VOCs) in garlic. SFB drying better preserves 6-gingerol than FD and HAD. MW increases trisulfides and cyclic sulfur compounds in garlic. In general, drying, especially thermal drying reduces the VOCs in fresh garlic, ginger, and scallion and causes the formation of new VOCs.

Aroma-active compounds in Russian sturgeon (Acipenser gueldenstaedtii) raised in recirculating aquaculture systems

The rearing system affects the nutritional and sensorial qualities of the Russian sturgeon (Acipenser gueldenstaedtii), a niche yet commercially valuable aquaculture species for caviar production. In the present work, we aimed to comprehensively characterize the odorant composition of fillets from Russian sturgeon raised in a recirculating aquaculture system (RAS) and discuss potential sources and formation pathways. A total of 114 odorants were detected through the application of combined sensory-instrumental analyses, of which 88 were successfully identified and 20 substances were found to be among the most potent odor constituents. The most dominant odorants were assigned to several specific substance classes, including aldehydes, alcohols, terpenes, ketones, organic acids, lactones, heterocycles, aromatic hydrocarbons, and sulfur-containing aldehydes. The compounds (E)-hex-2-enal, (Z)-hept-4-enal, cuminaldehyde, non-3-yn-1-ol, 3-carene, 2-methylisoborneol, geosmin, oct-1-en-3-one, nonan-3-one, (Z)-1,5-octadien-3-one, octane-2,3-dione, nonan-2-one, hexanoic acid, γ-crotonolactone, γ-octalactone, 2-acetyl-thiazoline, methional, and (2E,4Z,7Z)-trideca-2,4,7-trienal had high flavor dilution factors and are described for the first time as potent odor-active compounds associated with the Russian sturgeon. Overall, oct-1-en-3-one, (Z)-1,5-octadien-3-one, octane-2,3-dione, nonan-2-one, 2-methylisoborneol, and hexanoic acid had the highest flavor dilution factors. This study offers a basis for future development in the sturgeon RAS industry from the perspective of flavor characterization by providing deep insights into the fundamental composition and origins of the complex world of aquaculture fish aroma.

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.

Metagenomic and Metabolomic Profiling Reveals the Differences of Flavor Quality between Hongqu Rice Wines Fermented with Gutian Qu and Wuyi Qu.

Jiuqu (starter) makes an important contribution to the formation of the flavor characteristics of Hongqu rice wine (HQW). Gutian Qu (GTQ) and Wuyi Qu (WYQ) are two kinds of Jiuqu commonly used in HQW brewing, but the comparison of the two kinds of HQW is still insufficient at present. The objective of this study was to compare the dynamic changes of amino acids (AAs), higher alcohols (HAs), bioamines (BAs), volatile flavor compounds (VFCs), and microbial communities in HQW fermentation, with GTQ and WYQ as starter. This study used an automatic amino acid analyzer, GC, HPLC, and GC-MS to detect AAs, HAs, Bas, and VFCs during fermentation; metagenomic sequencing technology was used to elucidate the microbial community and its functional characteristics. The results showed that the contents of AAs and HAs in HQW brewed with WYQ (WYW) were significantly higher than those in HQW brewed with GTQ (GTW). On the contrary, the majority of BAs in GTW were significantly higher than those in WYW. The composition of VFCs in WYW and GTW were obviously different, as most of the VFCs were notably enriched in WYW, while ethyl caproate, isoamyl acetate, ethyl heptanoate, ethyl nonanoate, 1-decanol, citronellol, phenethyl acetate, and hexanoic acid were more abundant in GTW. Burkholderia gladioli, Pantoea dispersa, Weissella cibaria, Monascus purpureus, and Saccharomyces cerevisiae were the predominant microbial populations in GTW brewing at the species level, while Sphingomonas sp., Kosakonia cowanii, Enterobacter asburiae, Leuconostoc lactis, Aspergillus niger, and Saccharomyces cerevisiae were the dominant microbial species in WYW brewing. The abundance of functional genes involved in BAs biosynthesis were much higher in GTW brewing, while the abundance of functional genes related to the metabolism of characteristic VFCs were much higher in WYW brewing. Collectively, these findings provided evidence for elucidating the effects of Jiuqu and microbial communities on HQW flavor quality, and laid a solid foundation for the improvement of HQW flavor quality.

Dynamic Analysis of the Fruit Sugar-Acid Profile in a Fresh-Sweet Mutant and Wild Type in 'Shatangju' (Citrus reticulata cv.).

Citrate is a major determinant of fruit flavor quality. Currently, citrus species and/or varieties with significant alterations in citrate level have greatly advanced the molecular basis of citrate accumulation in fruit. However, in-depth dissections of the molecular mechanism specific to citrate accumulation are still limited due to the lack of mutants, especially within one single variety. In this study, a fresh-sweet 'Shatangju' mutant (Citrus reticulata cv.) was obtained during a survey of citrus resources in Guangdong, China, and the phenotype, fruit morphology, and primary flavor profiles were comparatively analyzed. Unlike the wild-type 'Shatangju' (WT), the mutant (MT) material exhibited a dwarfed and multi-branched tree shape, delayed flowering and fruit ripening at maturity, a prolonged fruit tree-retention time, and a decreased single fruit weight at maturity. Dynamic measurement of the metabolite levels further suggested that the contents and fluctuation patterns of vitamin C, malate, quinate, and oxalate showed no obvious difference between MT and MT fruits, while the citrate level in MT fruits significantly decreased over various developmental stages, ranging from 0.356 to 1.91 mg g-1 FW. In addition, the accumulation patterns of the major soluble sugars (sucrose, fructose, and glucose), as well as the sugar/acid ratio, were also altered in MT fruits during development. Taken together, this study provides a novel acid-free 'Shatangju' mutant, which can serve as a powerful tool for the research of fruit flavor quality, especially for the comprehensive understanding of the molecular mechanism of citrate accumulation in fruits.

Study on Sensory Quality and Flavor Characteristics of Jiangxiang Baijiu Produced by Different Fermentation Techniques

As a representative of traditional Chinese distilled liquor, the unique flavor of Sauce Flavor Baijiu is closely related to its brewing techniques. This study systematically explored the sensory quality and flavor characteristics of Sauce Flavor Baijiu produced by different fermentation techniques through sensory evaluation, gas chromatography analysis, and multivariate statistical methods. The results indicated that the techniques of Chuansha, Suisha, Kunsha, and their blends significantly influenced the concentration and proportion of flavor compounds in Baijiu, subsequently altering its aroma and taste. Specifically, Chuansha Baijiu exhibited weaker aroma and thinner taste; Suisha Baijiu presented certain complexity and a softer taste; while Kunsha Baijiu boasted a strong aroma and full-bodied taste. This study established a scientific quality evaluation system for Sauce Flavor Baijiu, providing theoretical foundations and technical support for the optimization of brewing techniques and improvement of Baijiu quality.

Insights into flavor quality and metabolites profiles of fresh cheese with different probiotics by SPME-GC-MS and untargeted metabolomics

In this study, fresh cheeses produced with four novel probiotics (Lactobacillus casei PB-LC39, Lactobacillus rhamnosus PB-LR76, Lactobacillus helveticus HH-LH17, and Lactobacillus plantarum HH-LP56) were named as LC, LR, LH, and LP, respectively. SPME-GC-MS and untargeted metabolomics were used to compare and analyze the flavor quality, metabolites and metabolic pathways of LC, LR, LH and LP, and the potential function of differential metabolites was emphasized. The results demonstrated that the incorporation of probiotics resulted in a significant increase in the number of volatile flavor compounds and varying flavor profiles within the cheese. Especially LC, exhibited aromas reminiscent of wine, fruit and rose, and displayed the most favorable flavor qualities among all probiotic cheeses. The results of differential metabolite screening and metabolic pathway demonstrated that probiotic cheese could result in the production of 146–192 differential metabolites, mainly carbohydrates, proteins and acids. Arginine biosynthesis was a key differential metabolite pathway made by probiotics. The LC, LR, LH, and LP groups contained 22, 27, 23, and 24 functional metabolites, including L-carnitine, naringenin, and turanose et al., which might confer anti-inflammatory and improve lipid metabolism functions. These findings provide a theoretical basis for the further functional evaluation and development of probiotic cheese.

Investigating the quality discrepancy between different salmon and tracing the key lipid precursors of roasted flavor

Differences in raw material characteristics directly affect the processing characteristics and quality of the final product. Therefore, it is important for the salmon industry to start regulating or grading from raw material side. In this study, the material characteristics and flavor quality of three different salmons: Atlantic salmon, red salmon, and pink salmon were evaluated. Trans-2,cis-6-nonadienal, octanal, and cis-4-heptenal contributed to the fishy aroma of roasted salmon, while fresh salmon was mainly caused by octanal. The oily aroma of fresh salmon was relevant to octanal, decanal, and 1-heptanol. The results indicated that the composition of phospholipids affect the flavor of roasted salmon, such as phosphatidylethanolamines and phosphatidylcholines, were closely related to the roasted and fishy aroma of roasted salmon. This study revealed that roasting could reduce the sensory quality difference between salmon by changing the textural property and volatile compound profile, provide guidance for production, grading, and consumption of salmon.

Investigation of in situ and ex situ mode of lactic acid bacteria incorporation and the effect on dough extensibility, bread texture and flavor quality during shelf-life

Lactococcus lactis subsp. diacetylactis, Lactobacillus delbrueckii subsp. bulgaricus, and Lb. rhamnosus were evaluated for their efficiencies in preserving bread texture and flavor during shelf-life. The investigated LABs exhibited efficiency during preliminary screening in expressing selected enzymes (protease, xylanase, α-amylase, laccase, and glucose oxidase) and producing exopolysaccharide (EPS). Dough samples were supplemented with either sourdough starters containing live LAB cells or LAB cell lysates. Prolonged fermentation further enhanced the protective advantage of sourdough starter incorporation. During the 5-day shelf-life period, in situ enrichment with Lb. rhamnosus led to a mere 12.5–35.4 % hardness change and 13.8–20.7 % overall texture change. Furthermore, sourdough bread with live LAB cell supplementation displayed a more diverse and intense flavor profile, with high concentration of bread key odorants maintained during shelf-life, including 2,3-butanedione, 2-acetyl-1-pyrroline, and 3-methylbutanal. Meanwhile, no significant improvement was found in bread enriched with LAB cell lysates during shelf-life.

Metagenomics reveals the differences in flavor quality of rice wines with Hongqu and Maiqu as the fermentation starters

Chinese rice wine (CRW) is an alcoholic beverage made mainly from rice or grain through saccharification and fermentation with Jiuqu (starter). Jiuqu makes an important contribution to the formation of the flavor characteristics of rice wine. Hongqu and Maiqu are two kinds of Jiuqu commonly used in CRW brewing. This study compared the microbial community, biogenic amines (BAs), and volatile flavor components (VFCs) of two types of rice wine brewed with Hongqu and Maiqu as fermentation agents. The results showed that the amino acid content of rice wine fermented with Maiqu (MQW) was significantly lower than that of rice wine fermented with Hongqu (HQW). On the contrary, the majority of BAs in MQW were significantly higher than those in HQW, except for putrescine. Multivariate statistical analysis indicated that most of the VFCs detected were enriched in HQW, while ethyl 3-phenylpropanoate and citronellol were enriched in MQW. The results of metagenomic analysis showed that Weissiella, Enterobacter, Leuconostoc, Kosakonia, Saccharomyces, Aspergilus and Monascus were identified as the predominant microbial genera in HQW brewing process, while Saccharopolyspora, Lactococcus, Enterobacter, Leuconostoc, Kosakonia, Pediococcus, Pantoea, Saccharomyces, Aspergillus, Lichtheimia and Nakaseomyces were the predominant microbial genera in MQW brewing. In addition, some VFCs and BAs were strongly correlated with dominant microbial genera in HQW and MQW brewing. Bioinformatics analysis showed that the abundance of genes involved in BAs synthesis in MQW brewing was much higher than that in HQW brewing, while the abundances of genes related to metabolic pathway of characteristic VFCs in HQW brewing were obviously higher than those in MQW, which explained the differences in flavor quality between HQW and MQW from the perspective of microbial genes. Collectively, these findings provide scientific evidence for elucidating the contribution of different microbial genera to the formation of flavor quality of CRW, and is helpful for screening beneficial microbes to enhance flavor quality and drinking comfort of CRW.