Fermented Soybean Products Research Articles

Thai Fermented Soybean (Thua-Nao) Prevents Early Stages of Colorectal Carcinogenesis Induced by Diethylnitrosamine and 1,2-Dimethylhydrazine Through Modulations of Cell Proliferation and Gut Microbiota in Rats.

Thua-nao is a traditional fermented soybean product widely consumed in the northern areas of Thailand. There has been little research on the biological activity of Thua-nao, particularly its anticancer properties. The objective of this study was to examine the cancer chemopreventive effects of dried Thua-nao on liver and colorectal carcinogenesis induced by carcinogens in rats. Rats were injected with diethylnitrosamine (DEN) and 1,2-dimethylhydrazine (DMH) to induce preneoplastic lesions. Rats orally received dried Thua-nao for 13 weeks. The preneoplastic lesions, including glutathione S-transferase placental form (GST-P)-positive foci and aberrant crypt foci (ACF), were evaluated in the liver and colon, respectively. The cancer chemopreventive mechanisms of dried Thua-nao on liver and colorectal carcinogenesis were examined. Dried Thua-nao administration suppressed colorectal aberrant crypt foci. Moreover, dried Thua-nao reduced proliferation cell nuclear antigen (PCNA)-positive cells in the colon. Interestingly, dried Thua-nao modulated the gut microbiota in DEN- and DMH-induced rats. Isoflavones, including genistein and daidzein, represent promising chemopreventive agents in dried Thua-nao. In conclusion, these results highlight the cancer chemopreventive effect of dried Thua-nao in DEN and DMH-induced colorectal carcinogenesis through cell proliferation reduction and gut microbiota modulation.

Traditionally produced tempeh harbors more diverse bacteria with more putative health-promoting properties than industrially produced tempeh

In recent years, there has been a significant shift towards industrialization in food production, resulting in the implementation of higher hygiene standards globally. Our study focused on examining the impact of hygiene standards on tempeh, a popular Rhizopus-based fermented soybean product native to Indonesia, and now famous around the world. We observed that tempeh produced with standardized hygiene measures exhibited a microbiome with comparable bacterial abundances but a markedly different community structure and function than traditionally produced tempeh. In detail, we found a decreased bacterial abundance of lactobacilli and enterobacteria, bacterial diversity, different indicator taxa, and significantly changed community structure in industrial tempeh. A similar picture was found for functional analysis: the quantity of bacterial genes was similar but qualitative changes were found for genes associated with human health. The resistome of tempeh varied based on its microbiome composition. The higher number of antimicrobial resistance genes in tempeh produced without standardized hygiene measures mainly belong to multidrug efflux pumps known to occur in plant-based food. Our findings were confirmed by functional insights into genomes and metagenome-assembled genomes from the dominant bacteria, e.g. Leuconostoc, Limosilactobacillus, Lactobacillus, Enterococcus, Paenibacillus, Azotobacter and Enterobacter. They harboured an impressive spectrum of genes important for human health, e.g. for production of vitamin B1, B7, B12, and K, iron and zinc transport systems and short chain fatty acid production. In conclusion, industrially produced tempeh harbours a less diverse microbiome than the traditional one. Although this ensures production at large scales as well as biosafety, in the long-term it can lead to potential effects for human gut health.

Improving natto quality through Co-fermentation of functionally complementary Bacillus and Lactiplantibacillus species

Natto, a nutritious fermented soybean product, is known for its health benefits. Modern production methods use Bacillus subtilis as the starter culture to ensure consistent quality. However, this method overlooks the potential positive effects of other microbial species present in traditionally, naturally fermented natto. This study explored the effects of ARTP-induced mutants of B. subtilis var. natto and several strains of lactic acid bacteria (LAB) on natto quality. The results showed that these two types of bacteria have complementary roles in fermentation. B. subtilis var. natto, with enhanced extracellular protease activity, promotes the hydrolysis of soy protein and enhances the product's ACE inhibitory and fibrinolytic activities. Meanwhile, two strains of Lactiplantibacillus plantarum reduced the content of total volatile basic nitrogen (TVB-N) while increasing the content of folic acid in the final product. In addition, B. subtilis var. natto and LAB produce different profiles of volatile compounds (VOCs). Subsequently, B. subtilis var. natto and Lpb. plantarum were used to co-ferment natto in different ratios. The results showed that the two types of bacteria could co-colonize and enhance fermentation quality through their respective strengths. Specifically, Lpb. plantarum strains co-metabolized with B. subtilis var. natto to elevate the content of pyrazines, characteristic VOCs in natto. The optimal quality of natto was achieved when Lpb. plantarum HIS6, Lpb. plantarum LP3 and B. subtilis var. natto Y15-11 were combined in a 2:1:2 ratio. This study not only identified effective combinations of starter cultures with complementary benefits but also elucidated the metabolic pathways of key volatile compounds. Our findings also provide technical insights for improving natto quality, enhancing consumer acceptance, and supporting industrial production.

Mini-Review: The Distinct Carbohydrate Active Enzyme Secretome of Rhizopus spp. Represents Fitness for Mycelium Remodeling and Solid-State Plant Food Fermentation.

Rhizopus is a genus of filamentous fungi belonging to the Mucoromycota division. Rhizopus species produce a white, dense mycelium, which is used to create tempeh, a solid-state fermented Asian soybean product, that is gaining renewed attention as a proteinaceous plant food. The profile of carbohydrate-active enzymes (CAZymes) of a fungus or group of fungi, particularly the secretome CAZymes profile, reflects adaptation to different lifestyles and habitats, and has a significant impact on fermentative capacity. This review examines the CAZymes profiles of Rhizopus species focusing on their implication for carbohydrate utilization and solid-state fermentation of plant materials. Through comprehensive genomic assessments and comparisons with other filamentous fungi, we particularly highlight how the unique CAZymes secretome profile is closely correlated with the taxonomy and ecological niches of Rhizopus species. We discuss how the CAZymes secretome capacity of Rhizopus species differs from other fungi and summarize the current state of knowledge regarding the specific CAZymes involved in the modification of carbohydrates in the fungal cell wall and in plant cell walls. We foresee that advanced genomic and proteomic technologies will be used to expand the biotechnology applications of Rhizopus spp.

Effect of drying techniques on the stability of volatile compounds and antioxidative activities of dried Thai fermented black soybean (thua nao)

Thua nao, a traditional fermented soybean product in Thailand, is widely consumed as a plant-based food or a condiment due to its distinct flavor, taste, and nutritional benefits. In this research, thua nao samples were produced from black soybeans. After fermentation, various drying methods, including sun drying (SUN), hot air drying (HOT), microwave vacuum drying (MIC), and vacuum drying (VAC) were employed to produce dried thua nao. The dried samples were stored under ambient conditions for 8 months. Results revealed lipid oxidation and the Maillard reaction occurred during storage, leading to a decline in bioactive compounds and antioxidant activities. Volatile aroma compounds were analyzed using solid-phase microextraction coupled with gas chromatography-mass spectrometry, while principal component analysis (PCA) evaluated aroma profile changes during storage. PCA indicated that HOT, MIC, and VAC -treated samples remained stable for up to 4 months, while SUN-treated samples changed after 2 months. It was found that SUN treatment prominently promoted the formation of oxidized volatile compounds associated with fatty-waxy and green attributes. The HOT treatment contributed more to aroma volatile compounds associated with nutty-roasted, floral, woody-smoky, and sweet attributes. While, both MIC and VAC treatments showed a noticeable loss of aroma volatile compounds, they retained higher level of bioactive compounds compared to the other treatments. This information aids in selecting suitable drying techniques for thua nao products and enhances understanding of chemical transformations induced by drying.

Monitoring and risk assessment of biogenic amines in commercial Thua-Nao, a traditional Northern Thai fermented soybean paste

Thua-Nao, a traditional fermented soybean product in Thailand, is susceptible to contamination with biogenic amines (BAs), thus increasing the risk to human health. The present study evaluated the contamination, formation, and risk assessments of BAs in two types of Thua-Nao. The elution conditions were optimized and used to analyze thua nao BAs with good correlation coefficients and high recovery. The average total BA content in dried Thua-Nao (D-TN; 342 mg/kg) was greater than that in fresh Thua-Nao (F-TN; 239 mg/kg), but the difference was not significant. Tyramine (TYM) was the dominant BA in thua nao, accounting for more than half of the total BAs in the majority of the samples, and it also exhibited a significant positive correlation with soluble protein and total BAs. The calculated highest estimated daily intake (EDI) and index of food safety (IFS) of TYM were 1.51 μg/kg/day and 0.008, respectively, among the age groups who consumed thua nao, indicating a low risk to human health. However, the acute risk index of TYM in F-TN and D-TN among patients taking monoamine oxidase inhibitors (MAOIs) was greater than 80 %. Thus, these results suggested that an adverse health effect is unlikely for the general population after excessive consumption of TYM-contaminated Thua-Nao, but it may have serious health implications for patients taking MAOIs.

Bioconversion of lignans in flaxseed cake by fermented tofu microbiota and isolation of Enterococcus faecium strain ZB26 responsible for converting secoisolariciresinol diglucoside to enterodiol

Human intestinal microbiota plays a crucial role in converting secoisolariciresinol diglucoside, a lignan found in flaxseed, to enterodiol, which has a range of health benefits: antioxidative, antitumor, and estrogenic/anti-estrogenic effects. Given the high secoisolariciresinol diglucoside content in flaxseed cake, this study investigated the potential of co-fermenting flaxseed cake with fermented soybean product to isolate bacterial strains that effectively convert secoisolariciresinol diglucoside to enterodiol in a controlled environment (in vitro). The co-fermentation process with stinky tofu microbiota significantly altered the lignan, generating 12 intermediate lignan metabolites as identified by targeted metabolomics. One particular promising strain, ZB26, demonstrated an impressive ability to convert secoisolariciresinol diglucoside. It achieved a conversion rate of 87.42 ± 0.33%, with secoisolariciresinol and enterodiol generation rates of 94.22 ± 0.51% and 2.91 ± 0.03%, respectively. Further optimization revealed, under specific conditions (0.5 mM secoisolariciresinol diglucoside, pH 8, 30 °C for 3 days), ZB26 could convert an even higher percentage (97.75 ± 0.05%) of the secoisolariciresinol diglucoside to generate secoisolariciresinol (103.02 ± 0.16%) and enterodiol (3.18 ± 0.31%). These findings suggest that the identified strains ZB26 have promising potential for developing functional foods and ingredients enriched with lignans.

Characterization and correlations of dominant microorganisms and volatile compounds in fermentation process of Yangjiang douchi.

Yangjiang douchi (YD) is a traditional fermented soybean product, which is popular in Chinese cuisine for its unique flavor. However, due to its high salt content and unstable flavor, its competitiveness in the international market is gradually weakening. Microorganisms have a key role in the production process of YD because it is a fermented food but the effect of microorganisms on the volatile compounds of YD is also not currently clear. In this paper, aroma compounds and microbial diversity in different fermentation stages of YD were analyzed using gas chromatography-mass spectrometry/olfactometry (GC-MS/O) and IlluminaMiseq system sequencing. A total of 78 aroma-active compounds were detected throughout the fermentation process and they influenced the formation of flavor in YD. Fungi flora were relatively single in YD, and bacteria were rich and varied. A total of 418 species of bacteria were present during fermentation, with unclassified_Staphylococcus, Staphylococcus_kloosii, and Bacillus_velezensis_Bacillus predominating. There were 25 species of fungi at the species level, and Aspergillus minisclerotigenes (OTU 4) played a dominant role in the whole fermentation process. Staphylococcus and Bacillus in the bacterial genus were strongly correlated with most flavor compounds detected, and A. minisclerotigenes in the fungi were more relevant to flavor compounds. This research provides a theoretical basis for the enhancement of the flavor of traditional fermented douchi in China. © 2024 Society of Chemical Industry.

Metabolic changes and isoflavone biotransformation in natto for improved nutritional distribution and bioavailability

We used LC-MS to identify the metabolic changes in soybean fermented by Bacillus subtilis DC-15 to comprehend the biochemical alterations. Total 650 distinct metabolites were observed, with amino acids, dipeptides, fatty acids, small molecule sugars, and isoflavones having the largest abundances. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the primary metabolic pathways involved during the fermentation of soybeans were related to amino acid metabolism, including beta-alanine metabolism, phenylalanine metabolism, glycine, serine, and threonine metabolism. In the gastric phase, the maximum amount of soy isoflavones was successfully converted from its glycoside form (50.04 μg/mL) to the aglycone form (104.07 μg/mL). The distribution of protein and lipid particles in natto during various stages of digestion showed changes from aggregated particles to more scattered particles. For the future development and enhancement of fermented soybean products, our metabolomic data can shed light on activated biochemical pathways and changes in metabolic pattern.

A comparative study on the nutritional composition, protein structure and effects on gut microbiota of 5 fermented soybean products (FSPs)

In this study, we conducted an analysis of the differences in nutrient composition and protein structure among various fermented soybean products and their impacts on the gut microbiota of rats. Conventional physicochemical analysis was employed to analyze the fundamental physicochemical composition of the samples. Additionally, we utilized high-performance liquid chromatography and ELISA techniques to quantify the presence of antinutritional compounds. Fourier infrared spectroscopy was applied to delineate the protein structure, while 16 s rRNA gene sequencing was conducted to evaluate alterations in gut microbiota abundance. Subsequently, KEGG was utilized for metabolic pathway analysis. Our findings revealed that fermented soybean products improved the nutritional profile of soybeans. Notably, Douchi exhibited the highest protein content at 52.18 g/100 g, denoting a 26.58 % increase, whereas natto showed a 24.98 % increase. Douchi and natto demonstrated the most substantial relative amino acid content, comprising 50.86 % and 49.04 % of the total samples, respectively. Moreover, the levels of antinutritional factors markedly decreased post-fermentation. Specifically, the α-helix content in doujiang decreased by 13.87 %, while the random coil content in soybean yogurt surged by 132.39 %. Rats that were fed FSP showcased notable enhancements in gut microbiota and associated metabolic pathways. A strong correlation was observed between nutrient composition, protein structure, and gut microbiota abundance. This study furnishes empirical evidence supporting the heightened nutritional attributes of FSPs.

Bioturbation effect of artificial inoculation on the flavor metabolites and bacterial communities in the Chinese Mao-tofu fermentation

A comparison between artificially inoculated Mao-tofu (CC) and naturally fermented Mao-tofu (MM) indicated that artificially adding Mucor plasmaticus to Mao-tofu dramatically enhanced the essential amino acid (EAA) content, as well as umami and sweet amino acids. Gas chromatography-tandem mass spectrometry (GC–MS/MS) analysis revealed that phenol (3.226 μg/g), 1-octen-3-ol (5.031 μg/g), ethyl heptanoate (1.646 μg/g), and indole (3.422 μg/g) were the key flavor components in Mao-tofu. Unlike MM, CC displayed a substantial increase in esters and a considerable decrease in foul odor substances, including sulfur-containing compounds and indole. Lactococcus raffinolactis, Enterobacter sp. 638, and Streptococcus parauberis KCTC 11537 represented the key bacterial species altering the amino acids and flavor of Mao-tofu according to PacBio single-molecule real-time (SMRT) sequencing and correlation analysis. This study presents the technical feasibility of artificially inoculating Mao-tofu to regulate the core bacterial communities and control the quality of fermented soybean products.

Consumption of poly-γ-glutamate-vitamin B6 supplement and urinary microbiota profiles in Korean healthy adults: a randomized, double-blinded, placebo-controlled intervention study.

Poly-γ-glutamic acid (γ-PGA), a natural polymer found in fermented soybean products, has been reported to play a prebiotic role in the gut. This intervention study investigated the effects of γ-PGA-containing supplement consumption on urinary microbiota in healthy adults because of limited data on such investigation. A 4-week parallel trial including 39 male and female Korean adults, who were free of chronic diseases and infection, was designed as a randomized, double-blinded, placebo-controlled study. A total of 30 participants completed the study wherein the intervention group (n = 17) received a mixture supplement containing 600 mg/day of γ-PGA and 100 mg/day of vitamin B6, while the control group (n = 13) received a placebo. Paired datasets (baseline and endpoint data) of microbiota profiles, which were constructed via urinary assays of microbe-derived extracellular vesicles, were analyzed and compared between the two groups. Only the intervention group yielded significant results for the Bray-Curtis and Jaccard dissimilarity indices between baseline and endpoint data (P < 0.05). In the phylum-level analysis of microbial composition, the Firmicutes to Bacteroidetes ratio (FB ratio) tended to decrease from baseline in the intervention group; however, it increased in the control group. Differences between the baseline and endpoint FB ratios were significant between the two groups (P < 0.05). This study's findings suggest that γ-PGA-vitamin B6 supplementation potentially alters the microbial community composition of a host. Further investigation into the biological consequences of commensal microbiota alteration by γ-PGA-containing supplement consumption is warranted.

Isoflavone aglycone contents of commercial fermented soybean products in Korea and the isoflavone aglycone-producing ability of &lt;i&gt;Bacillus subtilis&lt;/i&gt; isolated from the products

Isoflavone aglycone contents of commercial fermented soybean products in Korea and the isoflavone aglycone-producing ability of &lt;i&gt;Bacillus subtilis&lt;/i&gt; isolated from the products

Enzymatic Activity and Amino Acids Production of Predominant Fungi from Traditional Meju during Soybean Fermentation.

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to Mucoromycota, including Lichtheimia, Mucor, Rhizomucor, and Rhizopus, produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to Aspergillus subgenus circumdati. The genera Penicillium and Scopulariopsis produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to Aspergillus subgenus circumdati, including A. oryzae, showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of A. oryzae as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.

Construction of SERS output-signal aptasensor using MOF/noble metal nanoparticles based nanozyme for sensitive histamine detection

Herein, a signal output SERS aptasensor for Histamine (HA) detection is designed. MIL-100(Fe) was loaded with gold nanoparticles (AuNPs) to form composite nanozyme MIL-100(Fe)@AuNPs, which was used in the reaction system TMB/H2O2. Silver nanoparticles (AgNPs) were synthesized as “amplifier” for the SERS signal of ox TMB. After nucleic acid functionalization, the two parts were assembled to form the multifunctional substrate with both high catalytic and SERS efficiency. In the detection system, the specific binding effect of HA aptamer toward HA induced a decrease in the assembly of AgNPs on MIL-100(Fe)@AuNPs which caused a decrease in ox TMB SERS signals. The linear relation of HA ranged from 10−11 M to 5 × 10−3 M with LOD as low as 3.9 × 10−12 M. Recovery ratio in fermented soybean products (94.42–105.75 %) proved the real sample applicability. The fabricated SERS aptasensor will provide technical support for the safety during food processing and storage.

Identification, Characterization, and Receptor Binding Mechanism of New Umami Peptides from Traditional Fermented Soybean Paste (Dajiang).

Dajiang, a traditional Chinese condiment, is made from fermented soybeans. It is highly popular among consumers as a result of its delicious umami flavor, which mainly originates from umami peptides. To examine the mechanism of umami taste in Dajiang, we selected Dajiang samples with strong umami taste and subjected them to purification and identification analysis using ethanol precipitation, gel chromatography, reversed-phase high-performance liquid chromatography, and ultraperformance liquid chromatography-tandem mass spectrometry. Subsequently, on the basis of toxicity and umami prediction analysis, we screened, synthesized, and characterized three novel bean umami peptides in Dajiang: TLGGPTTL, 758.4174 Da; GALEQILQ, 870.4811 Da; and HSISDLQ, 911.4713 Da. Their sensory threshold values were 0.25, 0.40, and 0.17 mmol/L, respectively. Furthermore, molecular docking results showed that hydrogen-bonding and hydrophobic interactions are important interaction forces in the binding of umami peptide to taste receptors. Ser147 and Glu148 of the T1R3 taste receptor are important amino acid residues for binding of the three umami peptides. This study uncovers the mechanism of umami-peptide-driven flavor in fermented soybean products.

Safety Analysis of Korean Cottage Industries' Doenjang, a Traditional Fermented Soybean Product: A Special Reference to Biogenic Amines.

The typical Korean diet contains a significant quantity of doenjang owing to its unique taste and health benefits. However, the presence of anti-nutritional and toxic substances, such as biogenic amines and microbial pathogens, in doenjang has resulted in a loss of revenue and poor consumer health. The present study focused on the identification and quantification of different biogenic amines, pathogenic Bacillus cereus, and yeast counts in 36 doenjang products (designated as De-1 to De-36, 500 g each) procured from the different cottage industries situated in different parts of the Republic of Korea. The results indicated, only three samples were contaminated with B. cereus, exceeding the recommended limit (4 log CFU/g) suggested by the national standards of Korea. A total of six distinct yeasts were identified in different doenjang samples, whose comprehensive enzymatic profiling suggested the absence of harmful enzymes such as N-acetyl-β-glucosaminidase, α-chymotrypsin, and β-glucuronidase. The biogenic amines were detected in the range of 67.68 mg/kg to 2556.68 mg/kg and classified into six major groups based on hierarchical cluster analysis. All doenjang samples contained tryptamine, putrescine, cadaverine, histamine, and tyramine, while 94.44% were positive for spermidine and spermine. The results documented the analysis of traditional cottage industry doenjang and suggest the need for constant monitoring to ensure the safety of food for the consumer.

Microbial community succession and its correlation with the dynamics of flavor compound profiles in naturally fermented stinky sufu.

Wuhan stinky sufu is a traditional fermented soybean product with a short ripening period and unique flavor. The aim of this study was to explore the characteristic flavor compounds and core functional microbiota of naturally fermented Wuhan stinky sufu. The results indicated that 11 volatile compounds including guaiacol, 2-pentylfuran, dimethyl trisulfide, dimethyl disulfide, acetoin, 1-octen-3-ol, (2E)-2-nonenal, indole, propyl 2-methylbutyrate, ethyl 4-methylvalerate, nonanal were characteristic aroma compounds, and 6 free amino acids (Ser, Lys, Arg, Glu, Met and Pro) were identified as taste-contributing compounds. 4 fungal genera (Kodamaea, unclassified_Dipodascaceae, Geotrichum, Trichosporon), and 9 bacterial genera (Lysinibacillus, Enterococcus, Acidipropionibacterium, Bifidobacterium, Corynebacterium, Lactococcus, Pseudomonas, Enterobacter, and Acinetobacter) were identified as the core functional microbiota with positive effects on the production of flavor compounds. These findings would enhance the understanding of core flavor-producing microorganisms in naturally fermented soybean products and potentially provide guidance for enhancing the quality of sufu.

Metagenomics and metagenome-assembled genomes analysis of sieng, an ethnic fermented soybean food of Cambodia

Sieng is an ethnic fermented soybean food of Cambodia. No information on microbial community structures and their roles in health benefits of sieng is available till date. Hence, we aimed to profile the microbial community structures, to infer predictive functionalities and to recover the high-quality metagenome-assembled genomes (MAGs). Bacillus subtilis was the most abundant species in sieng, followed by Tetragenococcus halophilus, Enterococcus sp., Brevibacillus borstelensis, B. cereus, B. glycinifermentans, Halanaerobium praevalens, Mammaliicoccus sciuri, Staphylococcus gallinarum, Enterococcus faecium, B. cytotoxicus, Aneurinibacillus migulanus, B. thermoamylovorans, Paenibacillus dendritiformis and B. velezensis. Predictive functional profiles of sieng revealed several KEGG pathways and detection of CRISPR-Cas proteins. Six high-quality MAGs were recovered and identified as Bacillus subtilis, B. velezensis, B. glycinifermentans, B. borstelensis, B. thermoamylovorans and Ligilactobacillus acidipiscis. Genome annotation of recovered genomes showed biomarker genes for encoding several functional properties. Comparative analysis of previously reported microbiota in similar Asian sticky fermented soybean foods of other countries viz. Kinema of India, Nepal and Bhutan, pe poke of Myanmar and cheonggukjang of Korea with sieng was also studied. The PCoA plot showed a discrete variation between sieng and metagenomes of other similar fermented soybean foods, based on species level. However, sieng metagenome recorded the presence of halophilic bacterial species in higher abundance unlike other fermented soybean products. The present work is the first report on microbial community structure, and metagenome-assembled genomes of sieng.

Kajian Produksi Dan Analisis Mutu Pangan Tradisional Sere Kedele Di Kabupaten Klungkung, Bali

&#x0D; &#x0D; &#x0D; Sere kedele is a traditional fermented soybean product. This type of food is processed by home industries, especially in Klungkung Regency and several areas in Gianyar. This research was conducted to obtain information related to the traditional production process and analysis of the quality of sere kedele, especially in the Klungkung Regency, Bali. This research carried out in two stages, namely a survei to determine the production process, raw/additional materials used, presentation method, production area, and distribution of sere kedele in Klungkung Regency. The second stage is to analyze the chemical properties of traditional sere kedele food in Klungkung Regency. The survei results show that there are five producers of sere kedele in the villages of Tusan, Tihingan, Galiran, Tojan, Akah and Besang. The processing of sere kedele is different for each producer, such as the length of boiling, the length of fermentation, and the stage of adding seasonings. The samples used in this study is raw sere kedele and fried sere kedele. Sere kedele mentah in Klungkung Regency contains water content 56.85%-60.85%, ash content 1.21%-1.34%, protein content 14.68%-22.04%, fat content 5.69%-9.62%, and carbohydrate content of 13.64%-15.16%. Meanwhile, fried soybean sere has a water content of 1.42%-4.46%, an ash content of 1.45%-1.83%, a protein content of 13.45%-30.65%, fat content of 36.14%-42,1%, and carbohydrate content is 26.78% -41.49%.&#x0D; Keywords: sere kedele, Klungkung, fermentation, traditional food&#x0D; &#x0D; &#x0D;