Formation Of Flavor Compounds Research Articles

Efficient preparation of oyster hydrolysate with aroma and umami coexistence derived from ultrasonic pretreatment assisted enzymatic hydrolysis

In the study, an efficient protease Neutrase®-Flavourzyme® (NF) was screened to prepare the umami-aroma flavor oyster hydrolysate. The effect of protease and ultrasonic pretreatment (UP) assisted by the optimal protease on the flavor substances was investigated. The results demonstrated that the optimal UP-NF (450 W) showed a higher amino acid nitrogen content of 0.34 g/100 mL compared to the NF, and 19 major aroma compounds including octanal, decanal, nonanal, benzaldehyde, 2-undecanone, and 1-octen-3-ol were obtained. Additionally, the free amino acid and fatty acid spectrum indicated that the formation of flavor compounds was primarily due to the oxidation of linoleic and linolenic acids and the degradation of amino acids. Furthermore, taste analysis proved that increased umami and saltiness resulted from the accelerated release of Glu, Asp and 5′-IMP. Overall, UP-NF proved to be an effective method for producing umami-aroma flavor, facilitating further processing of oyster products for the application.

Relationship between the Dynamics of Flavor Compounds and Microbial Succession in the Natural Fermentation of Zhalajiao, a Popular Traditional Chinese Fermented Chili Paste.

Zhalajiao, a traditional Chinese fermented food, is popular due to its unique flavor. Traditional Zhalajiao fermentation is closely related to flavor compounds production. However, the mechanisms underlying the formation of these crucial flavor components in Zhalajiao remain unclear. Here, we explored the dynamic changes in physical and chemical properties, microbial diversity, and flavor components of Zhalajiao at various fermentation times. In total, 6 organic acids, 17 amino acids, and 21 key volatile compounds were determined as flavor components. In Zhalajiao, Lactobacillus and Cyanobacterium were the main bacteria that were involved in the formation of crucial flavor compounds. Candida showed a significant correlation with 14 key flavor compounds during fermentation (p < 0.05) and was the main fungal genus associated with flavor formation in Zhalajiao. This research offers a theoretical foundation for the flavor regulation and quality assurance of Zhalajiao.

The regulation of key flavor of traditional fermented food by microbial metabolism: A review.

The beneficial microorganisms in food are diverse and complex in structure. These beneficial microorganisms can produce different and unique flavors in the process of food fermentation. The unique flavor of these fermented foods is mainly produced by different raw and auxiliary materials, fermentation technology, and the accumulation of flavor substances by dominant microorganisms during fermentation. The succession and metabolic accumulation of microbial flora significantly impacts the distinctive flavor of fermented foods. The investigation of the role of microbial flora changes in the production of flavor substances during fermentation can reveal the potential connection between microbial flora succession and the formation of key flavor compounds. This paper reviewed the evolution of microbial flora structure as food fermented and the key volatile compounds that contribute to flavor in the food system and their potential relationship. Further, it was a certain guiding significance for food industrial production.

Contribution of Additional Glutamic Acid and Fructose in The Formation of Flavor Compounds in Green Tea

Green tea in Indonesia has an astringent and bitter taste due to its high catechin content. Adding amino acids and reducing sugars in green tea processing will increase the desirable flavor and cover the astringent and bitter flavors by increasing the Maillard reaction. Research on the manufacture of green tea with the addition of glutamate and fructose in fresh tea leaves has never been explored. This study aims to find a combination of glutamic acid (0%, 0.35%, 0.7%, 1.05%, 1.4%) and fructose (0%, 0.13%, 0.26%, 0.39%, 0.52%) to improve the flavor profile in green tea. The samples were evaluated for their antioxidant activity, amino acid, volatile, sensory evaluation, and color analysis. The results showed that adding glutamate and fructose increased the antioxidant activity of amino acid compounds and decreased the catechin content in green tea. Thus, the best treatment obtained was glutamate (1.05%) and fructose (0.26%), which increased the Maillard reaction in the formation of flavor compounds in green tea.

Changes in Microbial Communities and Volatile Compounds during the Seventh Round of Sauce-Flavor baijiu Fermentation in Beijing Region

Sauce-flavor baijiu products produced in different regions have perceptible differences in flavor characteristics, but the reasons for the formation of regional flavor substances are still unclear. The brewing process of sauce-flavor baijiu includes multiple rounds of pit fermentation. The base baijiu produced at the end of pit fermentation contributes significantly to the flavor of sauce-flavor baijiu products. This study investigated the microbial community succession and changes in flavor compounds during 7th round pit fermentation of sauce-flavor baijiu produced in Beijing region and comparatively analyzed the componential differences in microbial community and flavor compounds with sauce-flavor baijiu produced in other regions. It was found that Lactobacillus, Virgibacillus, Thauera, and Kroppenstedtia were the dominant bacterial genera, and Byssochlamys, Cutaneotrichosporon, and Apiotrichum were the dominant fungal genera. A total of 47 volatile compounds were identified and quantified in fermented grains. The concentrations of ethyl L(-)-lactate, ethyl caproate, and diethyl succinate gradually decreased with time, while the concentrations of phenethyl acetate, ethyl palmitate, and ethyl phenylacetate increased. The relative abundance of dominant microorganisms as well as the concentrations of volatile compounds showed a successional pattern with fermentation time. Lactobacillus, Virgibacillus, and Kroppenstedtia were positively associated with the synthesis of ethyl phenylacetate and phenylethyl alcohol, while negatively associated with the synthesis of ethyl caproate. Differences in microbial community structure are partly responsible for the regional flavor characteristics of sauce-flavor baijiu and the flavor differences between rounds of base baijiu. This study will provide in-depth insights into the formation of regional flavor compounds of sauce-flavor baijiu.

Effect of organic acid-soaking and sonication on the formation of volatile compounds and α-dicarbonyl compounds in Robusta coffee

In this study, the effects of organic acid-soaking (malic, citric, tartaric, and succinic acid) and sonication on the formation of flavor and α-dicarbonyl compounds in Robusta (C. canephora syn. Coffea robusta) green beans were investigated. A total of 20 volatile compounds were identified in Robusta coffee. Furfural and 5-methyl furfural, two dominant volatile compounds in Arabica coffee, increased after organic acid pretreatment. In Robusta coffee processed from 3% malic acid-soaked coffee beans, furfural and 5-methyl furfural increased by 90.99% and 24.92%, respectively, compared to the control. In Robusta coffee processed from 3% malic acid-sonicated (280 W, 1 h) coffee beans, furfural and 5-methyl furfural increased by 236.03% and 114.77%, respectively. α-Dicarbonyls (glyoxal, methylglyoxal, and diacetyl) were significantly (p < 0.05) decreased in all Robusta coffees after organic acid pretreatment. In Robusta coffee processed from coffee beans soaked and sonicated in tartaric acid solution, the α-dicarbonyls decreased by up to 44% and 58%, respectively, compared to the control. This study suggested the pretreatment methods to enhance the flavor substances and reduce the α-DCs in Robusta coffee.

Fermentation-promoting effect of three salt-tolerant Staphylococcus and their co-fermentation flavor characteristics with Zygosaccharomyces rouxii in soy sauce brewing

Staphylococcus is the dominant genus in the fermentation process of soy sauce, but its effect on the flavor of soy sauce has not been clearly established. In order to investigate the role of this genus in soy sauce fermentation, individual fermentation with Staphylococcus spp. screened from the moromi and their co-fermentation with an ester-producing yeast of Zygosaccharomyces rouxii were designed. Through the analysis of physicochemical properties, organic acid composition, volatile flavor compounds (VFCs) and sensory characteristics during fermentation, Staphylococcus was confirmed as a contributor to the acidity, ester aroma and alcohol aroma of soy sauce. In their co-fermentation with yeast, the ester aroma of soy sauce was further enhanced. Moreover, pathway enrichment analysis and network construction of key VFCs also revealed potential metabolic networks for formation of characteristic flavor compounds in co-fermentation. This work will help optimize the fermentation functional microbiota to obtain better soy sauce flavor.

The number and position of unsaturated bonds in aliphatic aldehydes affect the cysteine-glucose Maillard reaction: Formation mechanism and comparison of volatile compounds

Nonanal, (E)-2-nonenal, (E,E)-2,4-nonadienal, and (E,Z)-2,6-nonadienal were used to reveal the effect of the number and position of unsaturated bond in aliphatic aldehydes on Maillard reaction for the generation of 88 stewed meat-like volatile compounds. The results showed that (E,E)-2,4-nonadienal and (E,Z)-2,6-nonadienal exhibited greater inhibition of the cysteine reaction with glucose than nonanal and (E)-2-nonenal. However, the positions of the unsaturated bonds in aliphatic aldehydes in the Maillard reaction stage were similar. A carbohydrate module labeling approach was used to present the formation pathways of 34 volatile compounds derived from the Maillard reaction with aliphatic aldehyde systems. The number and position of unsaturated bonds in aliphatic aldehydes generate multiple pathways of flavor compound formation. 2-Propylfuran and (E)-2-(2-pentenyl)furan resulted from aliphatic aldehydes. 5-Butyldihydro-2(3H)-furanone and 2-methylthiophene were produced from the Maillard reaction. 2-Furanmethanol, 2-thiophenecarboxaldehyde, and 5-methyl-2-thiophenecarboxaldehyde were derived from the interaction of aliphatic aldehydes and the Maillard reaction. In Particular, the addition of aliphatic aldehydes changed the formation pathway of 2-propylthiophene, thieno[3,2-b]thiophene, and 2,5-thiophenedicarboxaldehyde. Heatmap and PLS-DA analysis could discriminate volatile compound compositions of the five systems and screen the marker compounds differentiating volatile compounds.

Environmental factors induced metabolome shifts during Laobaigan-flavor Baijiu fermentation

Environmental factors are the key factors affecting the fermentation of traditional fermented foods. However, the effects of environmental factors on flavor metabolism of Laobaigan-flavor Baijiu have not been described. In this study, we applied HS-SPME–GC–MS and physicochemical parameters analysis to reveal the dynamic of volatile flavor compounds and environmental factors, and indicated the effects of environmental factors on the succession of volatile flavor compounds. The fermentation process was divided into three stages: alcohols (628 mg/kg) and acids reached higher in the early stage (0–8 days), while aldehydes existed more in the middle stage (10–17 days) and esters accumulated until the middle (2501 mg/kg) or later (1168 mg/kg) stages (20–29 days). Meanwhile, environmental factors changed rapidly (p < 0.05), and significantly correlated with the formation of flavor compounds at different stages. Among them, pH and protein content were significantly related to esters (|r| > 0.6) esterified by monocarboxylic acid in the middle stage, while esters (|r| > 0.7) synthesized with hydroxyl acid had significant relations with temperature and moisture in the later stage. Our study indicated the correlations between the dynamic of environmental factors and the succession of volatile flavor compounds, and it provided a potential approach to manage environmental factors to improve the fermentation of Baijiu.

Microbial communities and their correlation with flavor compound formation during the mechanized production of light-flavor Baijiu

Light-flavor Baijiu fermentation is a typical spontaneous solid-state fermentation process fueled by a variety of microorganisms. Mechanized processes have been increasingly employed in Baijiu production to replace traditional manual operation processes, however, the microbiological and physicochemical dynamics in mechanized processes remain largely unknown. Here, we investigated the microbial community succession and flavor compound formation during a whole mechanized fermentation process of light-flavor Baijiu using the conventional dilution plating method, PacBio single-molecule real-time (SMRT) sequencing and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The results showed that largely different fungal and bacterial communities were involved in the soaking and fermentation processes. A clear succession from Pantoea agglomerans to Bacillus (B.) smithii and B. coagulans in dominant bacterial species and from Cladosporium exasperatum to Saccharomyces cerevisiae and Lichtheimia ramosa in dominant fungal species occurred in the soaking processes. In the fermentation process, the most dominant bacterial species was shifted from Pantoea agglomerans to Lactobacillus (La.) acetotolerans and the most dominant fungal species were shifted from Lichtheimia ramose and Rhizopus arrhizus to Saccharomyces cerevisiae. The bacterial and fungal species positively associated with acidity and the formation of ethanol and different flavor compounds were specified. The microbial species exhibited strong co-occurrence or co-exclusion relationships were also identified. The results are helpful for the improvement of mechanized fermentation process of light-flavor Baijiu production.

Rare short- and medium-chain fatty acid-producing anaerobes from raw soil play vital roles in formation of diverse flavour compounds of Jiangxiangxing Baijiu.

Pit mud is an essential habitat for diverse anaerobes, however, how pit mud of Jiangxiangxing Baijiu contributes to flavour is still unclear. The correlation between pit mud anaerobes and flavour compounds formation was investigated by analyzing flavour compounds and prokaryotic community of pit mud as well as fermented grains. Then scaling-down fermentation and culture-dependent approach were used to verify the effects of pit mud anaerobes on flavour compound formation. We found that short- and medium-chain fatty acids and alcohols, e.g., propionate, butyrate, caproate, 1-butanol, 1-hexanol, and 1-heptanol, were the vital flavour compounds produced by pit mud anaerobes. Pit mud anaerobes hardly migrated into fermented grains because of the low pH and low moisture of fermented grains. Therefore, the flavour compounds produced by pit mud anaerobes might enter fermented grains via volatilization. Moreover, enrichment culturing proved that raw soil was one of the sources for pit mud anaerobes, e.g., Clostridiumtyrobutyricum, Ruminococcaceae bacterium BL-4 and Caproicibacteriumamylolyticum. These rare short- and medium-chain fatty acid-producing anaerobes in raw soil can be enriched during Jiangxiangxing Baijiu fermentation. These findings clarified the role of pit mud during Jiangxiangxing Baijiu fermentation and revealed the key species involved in short- and medium-chain fatty acid-producing production.

Characterization of Flavor Profile of "Nanx Wudl" Sour Meat Fermented from Goose and Pork Using Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) Combined with Electronic Nose and Tongue.

Sour meat is a highly appreciated traditional fermented product, mainly from the Guizhou, Yunnan, and Hunan provinces. The flavor profiles of sour meat from goose and pork were evaluated using gas chromatography-ion mobility spectrometry (GC-IMS) combined with an electronic nose (E-nose) and tongue (E-tongue). A total of 94 volatile compounds were characterized in fermented sour meat from both pork and goose using GC-IMS. A data-mining protocol based on univariate and multivariate analyses revealed that the source of the raw meat plays a crucial role in the formation of flavor compounds during the fermentation process. In detail, sour meat from pork contained higher levels of hexyl acetate, sotolon, heptyl acetate, butyl propanoate, hexanal, and 2-acetylpyrrole than sour goose meat. In parallel, sour meat from goose showed higher levels of 4-methyl-3-penten-2-one, n-butyl lactate, 2-butanol, (E)-2-nonenal, and decalin than sour pork. In terms of the odor and taste response values obtained by the E-nose and E-tongue, a robust principal component model (RPCA) could effectively differentiate sour meat from the two sources. The present work could provide references to investigate the flavor profiles of traditional sour meat products fermented from different raw meats and offer opportunities for a rapid identification method based on flavor profiles.

Enhancement of the aromatic alcohols and health properties of Chinese rice wine by using a potentially probiotic Saccharomyces cerevisiae BR14

In recent years, potential probiotic strains have been increasingly applied to food to promote consumer health or improve the nutrition of products. In current study, a potential probiotic Saccharomyces cerevisiae strain BR14 was applied for the development of functional Huangjiu. The strain significantly increased the ethanol content in final wine, as well as the total acidity, especially acetic acid and lactic acid. As an accessory starter, BR14 promoted the formation of total volatile flavor compounds, particularly in 1-propanol, 3-methyl-1-butanol and phenethyl alcohol. Meanwhile, it reduced the formation of 2-Methyl-1-propanol by 54.65%. Regarding nutrients and functionality of final Chinese rice wine, S. cerevisiae BR14 exhibited excellent capacity in the improvement of glutamic acid, ornithine and antiradical activity for wine production. Content of urea, which determined the formation of ethyl carbamate, considerably decreased by the co-fermentation of BR14. Moreover, polysaccharide of Huangjiu fermented by BR14 stimulated the proliferation of macrophages RAW264.7, and reduced anti-inflammatory response. Based on sensory evaluation, BR14 wine was highly assessed for its intensive levels in alcohol-aroma and full body. This study verified the biofunctions of BR14, indicating the possibility to apply potential probiotic yeasts in food applications.

Integrative proteomic-transcriptomic analysis revealed the lifestyles of Lactobacillus paracasei H4-11 and Kluyveromyces marxianus L1-1 under co-cultivation conditions

Compared with the rice-acid soup inoculated with single starter, the synergistically intensified rice-acid soup inoculated with Lactobacillus paracasei H4-11 (L. paracasei H4-11) and Kluyveromyces marxianus L1-1 (K. marxianus L1-1) contained more flavor compounds. Organic acids mainly included L-lactic acid and the main volatile flavor component was ethyl acetate. Moreover, the signal intensity of astringency and bitterness and the total concentration of volatile sulfur compounds were reduced. The combined analysis results of RNA sequencing (RNA-seq) technology and 4D label-free quantitative (4D LFQ) proteomics explained the flavor formation pathways in rice-acid soup inoculated with L. paracasei H4-11 and K. marxianus L1-1. In L. paracasei H4-11, L-lactate dehydrogenase, phosphoglucomutase, acetate kinase, alcohol dehydrogenase and acetyl-CoA were up-regulated and D-lactate dehydrogenase and N-Acetyltransferase were down-regulated. In K. marxianus L1-1, Acetyl-CoA, acetaldehyde dehydrogenase, acyl-coenzyme A, N-acetyltransferase, and L-lactate dehydrogenase were up-regulated and hexokinase, alcohol dehydrogenase, and alcohol O-acetyltransferase were down-regulated. The above up-regulation and down-regulation synergistically promoted the formation of characteristic flavor compounds (mainly L-lactic acid and ethyl acetate). Enzyme-linked immunoassay (ELISA) and parallel reaction monitoring (PRM) quantitative analysis respectively verified that 5 key metabolic enzymes and 27 proteins in L. paracasei H4-11 and K. marxianus L1-1 were associated with the characteristic flavor of rice-acid soup, as confirmed by the quantitative results of 4D LFQ.

Mechanism of Carbon Skeleton Formation of 2,3,5-Trimethylpyrazine via a Conversion Reaction between Methylglyoxal and Glyoxal.

Maillard flavor compounds, such as 2,3,5-trimethylpyrazine, have been frequently identified in thermally processed food products, such as popcorn and peanuts. However, the origin of the carbon atoms in 2,3,5-trimethylpyrazine has not been clearly elucidated. Herein, a model reaction showed that precursor methylglyoxal and intermediates glyoxal and formaldehyde contributed to the formation of 2,3,5-trimethylpyrazine via a conversion reaction between methylglyoxal and glyoxal. In addition, carbon module labeling technology and model response validation experiments indicated that this transformation reaction between methylglyoxal and glyoxal brought formaldehyde into the methyl group carbon atoms of the 2,3,5-trimethylpyrazine ring. The proposed novel route provides a new perspective for approaches to control the formation of flavor compounds, such as 2,3,5-trimethylpyrazine.

Effect of salts on the formation of acrylamide, 5-hydroxymethylfurfural and flavour compounds in a crust-like glucose/wheat flour dough system during heating

Among many strategies known to mitigate acrylamide formation, addition of cations, particularly calcium, is effective and can be used in bakery products. In this study, the effects of NaCl, KCl, CaCl2, MgCl2, sodium lactate, calcium lactate, and magnesium lactate on aroma and acrylamide formation were investigated in glucose/wheat flour dough systems during heating. Addition of salts inhibited Maillard reaction in favour of caramelisation, with divalent cations found to be most effective. The impact of salts on acrylamide reduction became less effective with increasing temperature. Most Strecker aldehydes and pyrazines decreased in the presence of salts, however CaCl2 and calcium lactate increased the concentration of furans, furfurals, and diketones. Calcium lactate also increased some ethyl-substituted pyrazines at high temperatures. Reduction of acrylamide with salts is associated with higher amounts of furan derivatives and decreased amounts of Strecker aldehydes and pyrazines. The mechanisms behind these changes are discussed.

Microbial diversity of milk ghee in southern Gansu and its effect on the formation of ghee flavor compounds.

Ghee is a traditional Tibetan dairy product with high-fat content, low yield, plasticity, caseation, and rich nutrition. In this study, we analyzed the diversity of microbial communities in yak milk and ghee samples at high and low altitudes, especially the Lactobacillus genus, and further used metabolomic techniques to compare the differences in metabolites in yak ghee at different altitudes. The results showed that the increase in altitude had a significant and generally inhibitory effect on the microbial community diversity in milk ghee, and yak milk at high altitude was abundant in nutrients, which could antagonize the negative impact of increased altitude. Using non-targeted metabolomics, we infer the composition of flavor compounds in ghee: nine kinds of carboxylic acids, 11 kinds of esters, six kinds of ketones, two kinds of alcohols, and four kinds of alkene compounds, among which the key flavor compounds are dl-2-(acetylamino)-3-phenylephrine acid, 1-(4-methoxyphenyl)-2-propanone, sebacic acid, Lysope 18:1, and uracil 1-beta-d-arabinofuranoside. These flavor substances are found in Lactococcus, Lactobacillus, and Streptococcus. With the participation of Lactobacillus, it is synthesized through biosynthesis of alkaloids derived from ornithine, lysine, and nicotine acid and glyoxylate and decarboxylate metabolism, among which Lactococcus plays a key role. In this study, a variety of lactic acid bacteria related to ghee fermentation were screened out, revealing the composition of volatile flavor compounds in Gannan yak milk ghee in the Qinghai-Tibet Plateau and providing a reference for further key volatile flavor compounds and the formation mechanism of flavor compounds.

Acrylamide, a toxic maillard by-product and its inhibition by sulfur-containing compounds: A mini review

The Maillard reaction not only results in the formation of flavor compounds, but also harmful by-products, including the infamous toxicant acrylamide. Dietary acrylamide cannot be eliminated, but its levels in foods can be minimized. This review discusses the mechanisms of inhibition, effectiveness under varied conditions, and limitations of the sulfur-containing compounds: thiols, sulfites, thioethers, and thiosulfinates. These compounds have proven to be effective inhibitors of acrylamide formation. Among these compounds, the thiols are deemed the most effective. However, such success is masked by their negative effects on food taste and odor.

Correlation between microbe, physicochemical properties of Jiuqu in different plateau areas and volatile flavor compounds of highland barley alcoholic drink

Highland barley alcoholic drink (HBD), as one of the most typical rice wines in Qinghai-Tibet plateau area, is generally brewed by adding Jiuqu to highland barley. However, the flavor and quality of HBD fermented with Jiuqu in various plateau regions are different. This study elucidated the potential correlation between the microbial community, physicochemical properties of five traditional plateau Jiuqu, namely Hongxin1 (HX1), Hongxin2 (HX2), Huairang (HR), Hoarfrost gypsophila (HG) and Tibet Qu (TQ), and volatile flavor compounds of HBD. Based on high-throughput sequencing (HTS) technology and LEfSe analysis, it was found that the bacteria and fungi of the five traditional plateau Jiuqu were quite different. Differential microorganisms were Weissella and Pichia in HX1, Lactococcus and Kazachstania in HR, Acetobacter and Rhizopus in TQ. Besides, HX1 and HX2 had higher esterification power, TQ had the highest fermentation power while HR had the lowest enzymatic properties. Finally, RDA and Pearson correlation analysis showed that esterification power and moisture content had positive effects on Lactobacillus, fermentation power and saccharification power were highly positively correlated with Pantoea and Rhizopus, but negatively correlated with Aspergillus. In flavor analysis, Rhizopus, Acetobacter were found positively correlated with alcohols and acids, which contributed to the formation of volatile flavor compounds, Lactobacillus_sanfranciscensis and Lactobacillus_sakei were positively correlated with phenolic compounds. This study showed that the flavor of HBD was seriously affected by the microbiota in Jiuqu, which could help to develop new fortified starter to improve the quality of HBD.

Study on the safety and excellent probiotic properties of fermentation strains isolated from traditional dry-cured duck for starter development

The indigenous starter cultures isolated from fermented food can compete with spoilage and pathogenic bacteria and improve the flavor and organoleptic properties of products. The purposes of this work were to screen and assess the safety, potential probiotic, and fermentation properties of indigenous starter cultures isolated from dry-cured ducks. The properties of indigenous starter cultures were investigated by antibiotic resistance, virulence genes, in vivo toxicity, simulated gastrointestinal, adhesion capacity to Caco-2 cells, inoculation fermentation, etc. Overall, six strains were isolated and identified, including Lactobacillus sakei D15, Weissella hellenica D20, Lactobacillus curvatus D2, Staphylococcus simulans D12, Staphylococcus equorum D19, and Staphylococcus edaphicus D17. The obtained strains showed high safety. Additionally, most strains displayed excellent probiotic properties, including tolerance to lower pH, lysozyme, bile salt, and a high survival rate of the simulated gastrointestinal phase. The adhesion ability of strain cells to Caco-2 cells was 9.22%–14.21%. And the probiotic properties of strains can be strengthened by the expression of specific enzymes. The inoculation with the isolated strains (LS-D15, LC-D2 and SS-D12) could contribute to the formation of volatile flavor compounds in samples. Overall, results demonstrated that strains possessed excellent safety and probiotic properties, and can be used as starter cultures to enhance the quality and flavor of the dry-cured duck.