Cocoa Fermentations Conducted with a Defined Microbial Cocktail Inoculum

Cocoa fermentations were performed in wooden boxes under the following four experimental regimens: beans naturally fermented with wild microflora; aseptically prepared beans with no inoculum; and beans inoculated with a defined cocktail containing microorganisms at a suitable concentration either at zero time or by using phased additions at appropriate times. The cocktail used consisted of a yeast, Saccharomyces cerevisiae var. chevalieri, two lactic acid bacterial species, Lactobacillus lactis and Lactobacillus plantarum, and two acetic acid bacterial species, Acetobacter aceti and Gluconobacter oxydans subsp. suboxydans. The parameters measured were cell counts (for yeasts, filamentous fungi, lactic acid bacteria, acetic acid bacteria, and spore formers, including reisolation and identification of all residual cell types), sugar, ethanol, acetic acid, and lactic acid contents (and contents of other organic acids), pH, and temperature. A cut test for bean quality and a sensorial analysis of chocolate made from the beans were also performed. The natural fermentation mimicked exactly the conditions in 800-kg boxes on farms. The aseptic box remained largely free of microflora throughout the study, and no significant biochemical changes occurred. With the zero-time inoculum the fermentation was almost identical to the natural fermentation. The fermentation with the phased-addition inoculum was similar, but many changes in parameters were slower and less pronounced, which led to a slightly poorer end product. The data show that the nearly 50 common species of microorganisms found in natural fermentations can be replaced by a judicious selection and concentration of members of each physiological group. This is the first report of successful use of a defined, mixed starter culture in such a complex fermentation, and it should lead to chocolate of more reliable and better quality.     

Population dynamics and metabolite analysis of yeasts involved in a Chinese miscellaneous-flavor liquor fermentation

Baiyunbian liquor, the most popular miscellaneous-flavor liquor in China, is mainly produced in four successive fermentation batches every year. Sensory analysis based on the trained expert panel test revealed that the raw Baiyunbian liquor distilled from the last two fermentation batches always has higher quality than that distilled from the first two batches. In this study, the yeast composition, volatile compounds, and fermentation conditions associated with each fermentation batch were monitored. Significant differences were observed in the yeast community structure and fermentation parameters among different batches, which influenced the volatile profiles of the resulting liquors. Redundancy discriminate analysis and single-strain fermentation revealed that Pichia kudriavzevii and Candida humilis play important roles in enriching volatile compounds. Saccharomyces cerevisiae and Zygosaccharomyces bailii were the dominant yeasts in the last two fermentation batches. The sensorial characteristics of the liquors produced by single-strain fermentation were also analyzed. This study provides an in-depth understanding of the factors that influence liquor production and is beneficial in the development of new fermentation techniques with stable liquor quality.     

Microbial community and physicochemical dynamics during the production of ‘Chicha’, a traditional beverage of Indigenous people of Brazil

The microbial community of artisanal corn fermentation called Chicha were isolated, purified and then identified using protein profile by Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) and confirmed by partial ribosomal gene sequencing. Samples from Chicha beverage were chemically characterized by gas and liquid chromatography (HPLC and GC-MS). Aerobic mesophilic bacteria (AMB) (35.8% of total of isolated microorganisms), lactic acid bacteria (LAB) (21.6%) and yeast (42.6%) were identified. Species of the genera Klebsiella, Bacillus, Staphylococcus, Micrococcus, Enterobacter, and Weissella were identified. Rhodotorula mucilaginosa, Lodderomyces elongisporus, Candida metapsilosis, and C. bohicensis were the yeasts found. The LAB isolates detected were responsible for the high concentrations of lactic acid found during the fermentation process (1.2 g L^??1), which is directly related to the decrease in pH values (from 6.95 to 3.70). Maltose was the main carbohydrate detected during corn fermentation (7.02 g L^??1 with 36 h of fermentation). Ethanol was found in low concentrations (average 0.181 g L^??1), making it possible to characterize the beverage as non-alcoholic. Twelve volatile compounds were identified by gas chromatography; belonging to the groups acids, alcohols aldehydes, acetate and others. MALDI-TOF was successfully used for identification of microbiota. Weissella confusa and W. cibaria were detected in the final product (after 36 h of fermentation), W. confusa is often classified as probiotic and deserve further application studies.     

The impact of lactic acid bacteria on cheese flavor

Abstract Chesse flavor is a manifestation of complex interactions of volatile and non-volatile flavor-active compounds plus tactual perception. Numerous agents, including lactic acid bacteria, procece the flavou sensations. The effect of lactic acid bacteria is more dominant in cheese varieties with limited growth of secondary flora. This review describes the indirect and direct impacts of lactic acid bacteria in cheese with emphasis on carbohydrate fermentation, changes in oxidation-reduction potential, interactions with non-starter bacteria, autolysis, proteolytic and peptidolytic activities, transport of metabolites and flavor production.     

Coffee volatiles induced after mechanical injury and beetle herbivory attract the coffee berry borer and two of its parasitoids

The coffee berry borer (CBB), Hypothenemus hampei (Ferrari), is the most important insect pest of coffee worldwide. In this study, we used headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry to sample and identify volatile compounds from Robusta coffee berries, Coffea canephora Pierre ex Froehner, infested with CBB and with mechanical damage. Furthermore, we evaluated the behavioral responses of the CBB and two of its parasitoids, Prorops nasuta Waterstone and Phymastichus coffea LaSalle, to three selected coffee volatile compounds in a Y-tube olfactometer. We found in the effluvia of red coffee berry compounds not previously reported for this coffee species. Our results show that Robusta coffee berries release induced volatiles either by insect herbivory or by mechanical damage. Small amount of butyl acetate, unknown compound 2, α-longipinene, longiborneol and longiborneol acetate are produced only in infested coffee berries fruits. Quantitatively, nine compounds account for the difference between healthy berries, infested, or mechanically damaged berries. Trans-ocimene, 4,8-dimethyl-3,7-nonadien-2-ol, α-copaene and kaurene increased amount levels in infested berries, while amount of methyl salicylate and linalool increased in mechanically damaged coffee berries. The olfactometric bioassays showed that CBB females and its two parasitoids were attracted to methyl salicylate. In addition, H. hampei and P. nasuta were attracted to linalool, and P. nasuta and P. coffea were attracted to trans-ocimene.     

<Emphasis Type="Italic">In situ</Emphasis> fermentation dynamics during production of <Emphasis Type="Italic">gundruk</Emphasis> and <Emphasis Type="Italic">khalpi</Emphasis>, ethnic fermented vegetable products of the Himalayas

Gundruk is a fermented leafy vegetable and khalpi is a fermented cucumber product, prepared and consumed in the Himalayas. In situ fermentation dynamics during production of gundruk and khalpi was studied. Significant increase in population of lactic acid bacteria (LAB) was found during first few days of gundruk and khlapi fermentation, respectively. Gundruk fermentation was initiated by Lactobacillus brevis, Pediococcus pentosaceus and finally dominated by Lb. plantarum. Similarly in khalpi fermentation, heterofermentative LAB such as Leuconostoc fallax, Lb. brevis and P. pentosaceus initiated the fermentation and finally completed by Lb. plantarum. Attempts were made to produce gundruk and khalpi using mixed starter culture of LAB previously isolated from respective products. Both the products prepared under lab condition had scored higher sensory-rankings comparable to market products.     

The use of selected starter <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> strains to produce traditional and industrial cachaça: a comparative study

Six Saccharomyces cerevisiae strains from cachaça fermentation were characterized for biomass, ethanol, glycerol, and acetic acid yields, as well as productivity. Three strains presenting the best fermentation parameters were selected for cachaça production. The experiments were carried out in an industrial distillery that distills this beverage in a stainless steel column, and in a traditional distillery that uses copper alembic for distillation. The permanence of the selected strains was studied by restriction fragment analysis of mitochondrial DNA. Strains UFMG-A1007 and UFMG-A2097 were prevalent in the vats during the 5 days of the fermentation period. Non-Saccharomyces strains were isolated during the entire fermentation period. In general, the cachaças produced in the stainless steel column had the highest concentrations of volatile acidity, acetaldehyde, esters, and higher alcohols. Both cachaças did not differ statistically in aroma, taste, and overall impression. The use of these indigenous S. cerevisiae strains as starter ferment could improve the sensory attributes of both industrial and traditional cachaças.     

Ochratoxin A-producing Aspergilli in Vietnamese green coffee beans

AIMS: To determine the incidence and severity of infection by ochratoxin A (OA)-producing fungi in Vietnamese green coffee beans. METHODS AND RESULTS: Aspergillus carbonarius, A. niger and yellow Aspergilli (A. ochraceus and related species in section Circumdati) were isolated by direct plating of surface-disinfected Robusta (65 samples) and Arabica (11 samples) coffee beans from southern and central Vietnam. Significantly, more Robusta than Arabica beans were infected by fungi. Aspergillus niger infected 89% of Robusta beans, whereas A. carbonarius and yellow Aspergilli each infected 12-14% of beans. OA was not produced by A. niger (98 isolates) or A. ochraceus (77 isolates), but was detected in 110 of 113 isolates of A. carbonarius, 10 isolates of A. westerdijkiae and one isolate of A. steynii. The maximum OA observed in samples severely infected with toxigenic species was 1.8 microg kg(-1); however, no relationship between extent of infection and OA contamination was observed. CONCLUSIONS: Aspergillus niger is the dominant species infecting Vietnamese coffee beans, yet A. carbonarius is the likely source of OA contamination. SIGNIFICANCE AND IMPACT OF STUDY: Vietnamese green coffee beans were more severely infected with fungi than the levels reported for beans from other parts of the world, yet OA contamination appears to be infrequent.     

The cocoa bean fermentation process: from ecosystem analysis to starter culture development

Cocoa bean fermentation is still a spontaneous curing process to facilitate drying of nongerminating cocoa beans by pulp removal as well as to stimulate colour and flavour development of fermented dry cocoa beans. As it is carried out on farm, cocoa bean fermentation is subjected to various agricultural and operational practices and hence fermented dry cocoa beans of variable quality are obtained. Spontaneous cocoa bean fermentations carried out with care for approximate four days are characterized by a succession of particular microbial activities of three groups of micro‐organisms, namely yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB), which results in well‐fermented fully brown cocoa beans. This has been shown through a plethora of studies, often using a multiphasic experimental approach. Selected strains of several of the prevailing microbial species have been tested in appropriate cocoa pulp simulation media to unravel their functional roles and interactions as well as in small plastic vessels containing fresh cocoa pulp‐bean mass to evaluate their capacity to dominate the cocoa bean fermentation process. Various starter cultures have been proposed for successful fermentation, encompassing both cocoa‐derived and cocoa nonspecific strains of (hybrid) yeasts, LAB and AAB, some of which have been implemented on farms successfully.     

Lactic acid bacteria population dynamics during spontaneous fermentation of radish (<Emphasis Type="Italic">Raphanus sativus</Emphasis> L.) roots in brine

The aim of the present study was to assess the microecosystem development and the dynamics of the lactic acid bacteria population during spontaneous fermentation of radish (Raphanus sativus L.) roots in brine at 20 and 30?°C. In both temperatures, lactic acid bacteria prevailed the fermentation; as a result, the pH value was reduced to ca. 3.6 and total titrable acidity increased to ca. 0.4% lactic acid. Enterococci population increased and formed a secondary microbiota while pseudomonads, Enterobacteriaceae and yeasts/molds populations were below enumeration limit already before the middle of fermentation. Pediococcus pentosaceus dominated during the first days, followed by Lactobacillus plantarum that prevailed the fermentation until the end. Lactobacillus brevis was also detected during the final days of fermentation. A succession at sub-species level was revealed by the combination of RAPD-PCR and rep-PCR analyses. Glucose and fructose were the main carbohydrates detected in brine and were metabolized into lactic acid, acetic acid and ethanol.     

Identification and molecular genetic mapping of <Emphasis Type="Italic">Chili veinal mottle virus</Emphasis> (ChiVMV) resistance genes in pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis>)

Chili veinal mottle virus (ChiVMV) threatens the agricultural production of peppers (Capsicum annuum) in Asia and Africa. In this study, we evaluated ChiVMV resistance in the four pepper varieties CV3, CV4, CV8, and CV9. Segregation analyses revealed that CV3 and CV8 contain the single dominant resistance gene Cvr1, and CV9 contains the single recessive resistance gene cvr4. SNP markers were developed and used to map the Cvr1 gene in CV3 to the short arm of chromosome 6 where NLR genes are clustered. In CV4 oligogenic resistance loci were detected. A genotyping-by-sequencing (GBS) combined with modified sliding window approach mapped two resistance loci, to chromosomes 6 and 10. The development of SNP markers and the resulting knowledge of genomic positioning will assist in breeding ChiVMV-resistant pepper varieties and in the fine mapping of ChiVMV resistance genes.     

Incubation of <Emphasis Type="Italic">Aquilaria subintegra</Emphasis> with Microbial Culture Supernatants Enhances Production of Volatile Compounds and Improves Quality of Agarwood Oil

Incubation with microbial culture supernatants improved essential oil yield from Aquilaria subintegra woodchips. The harvested woodchips were incubated with de man, rogosa and sharpe (MRS) agar, yeast mold (YM) agar medium and six different microbial culture supernatants obtained from Lactobacillus bulgaricus, L. acidophilus, Streptococcus thermophilus, Lactococcus lactis, Saccharomyces carlsbergensis and S. cerevisiae prior to hydrodistillation. Incubation with lactic acid bacteria supernatants provided higher yield of agarwood oil (0.45% w/w) than that obtained from yeast (0.25% w/w), agar media (0.23% w/w) and water (0.22% w/w). The composition of agarwood oil from all media and microbial supernatant incubations was investigated by using gas chromatography-mass spectrometry. Overall, three major volatile profiles were obtained, which corresponded to water soaking (control), as well as, both YM and MRS media, lactic acid bacteria, and yeast supernatant incubations. Sesquiterpenes and their oxygenated derivatives were key components of agarwood oil. Fifty-two volatile components were tentatively identified in all samples. Beta-agarofuran, α-eudesmol, karanone, α-agarofuran and agarospirol were major components present in most of the incubated samples, while S. cerevisiae-incubated A. subintegra provided higher amount of phenyl acetaldehyde. Microbial culture supernatant incubation numerically provided the highest yield of agarwood oil compared to water soaking traditional method, possibly resulting from activity of extracellular enzymes produced by the microbes. Incubation of agarwood with lactic acid bacteria supernatant significantly enhanced oil yields without changing volatile profile/composition of agarwood essential oil, thus this is a promising method for future use.     

The bacterial and archaeal community structures and methanogenic potential of the cecal microbiota of goats fed with hay and high-grain diets

The cecum plays an important role in the feed fermentation of ruminants. However, information is very limited regarding the cecal microbiota and their methane production. In the present study, the cecal content from twelve local Chinese goats, fed with either a hay diet (0% grain) or a high-grain diet (71.5% grain), were used to investigate the bacterial and archaeal community and their methanogenic potential. Microbial community analysis was determined using high-throughput sequencing of 16S rRNA genes and real-time PCR, and the methanogenesis potential was assessed by in vitro fermentation with ground corn or hay as substrates. Compared with the hay group, the high-grain diet significantly increased the length and weight of the cecum, the proportions of starch and crude protein, the concentrations of volatile fatty acids and ammonia nitrogen, but decreased the pH values (P?<?0.05). The high-grain diet significantly increased the abundances of bacteria and archaea (P?<?0.05) and altered their community. For the bacterial community, the genera Bifidobacterium, Prevotella, and Treponema were significantly increased in the high-grain group (P?<?0.05), while Akkermansia, Oscillospira, and Coprococcus were significantly decreased (P?<?0.05). For the archaeal community, Methanosphaera stadtmanae was significantly increased in the high-grain group (P?<?0.05), while Methanosphaera sp. ISO3-F5 was significantly decreased (P?<?0.05). In the in vitro fermentation with grain as substrate, the cecal microorganisms from the high-grain group produced a significantly higher amount of methane and volatile fatty acids (P?<?0.05), and produced significantly lower amount of lactate (P?<?0.05). Conclusively, high-grain diet led to more fermentable substrates flowing into the hindgut of goats, resulting in an enhancement of microbial fermentation and methane production in the cecum.     

Interaction of <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis>–<Emphasis Type="Italic">Lactobacillus fermentum</Emphasis>–<Emphasis Type="Italic">Dekkera bruxellensis</Emphasis> and feedstock on fuel ethanol fermentation

The alcoholic fermentation for fuel ethanol production in Brazil occurs in the presence of several microorganisms present with the starter strain of Saccharomyces cerevisiae in sugarcane musts. It is expected that a multitude of microbial interactions may exist and impact on the fermentation yield. The yeast Dekkera bruxellensis and the bacterium Lactobacillus fermentum are important and frequent contaminants of industrial processes, although reports on the effects of both microorganisms simultaneously in ethanolic fermentation are scarce. The aim of this work was to determine the effects and interactions of both contaminants on the ethanolic fermentation carried out by the industrial yeast S. cerevisiae PE-2 in two different feedstocks (sugarcane juice and molasses) by running multiple batch fermentations with the starter yeast in pure or co-cultures with D. bruxellensis and/or L. fermentum. The fermentations contaminated with D. bruxellensis or L. fermentum or both together resulted in a lower average yield of ethanol, but it was higher in molasses than that of sugarcane juice. The decrease in the CFU number of S. cerevisiae was verified only in co-cultures with both D. bruxellensis and L. fermentum concomitant with higher residual sucrose concentration, lower glycerol and organic acid production in spite of a high reduction in the medium pH in both feedstocks. The growth of D. bruxellensis was stimulated in the presence of L. fermentum resulting in a more pronounced effect on the fermentation parameters than the effects of contamination by each microorganism individually.     

Microbiological and physicochemical characterization of small-scale cocoa fermentations and screening of yeast and bacterial strains to develop a defined starter culture

Spontaneous cocoa bean fermentations performed under bench- and pilot-scale conditions were studied using an integrated microbiological approach with culture-dependent and culture-independent techniques, as well as analyses of target metabolites from both cocoa pulp and cotyledons. Both fermentation ecosystems reached equilibrium through a two-phase process, starting with the simultaneous growth of the yeasts (with Saccharomyces cerevisiae as the dominant species) and lactic acid bacteria (LAB) (Lactobacillus fermentum and Lactobacillus plantarum were the dominant species), which were gradually replaced by the acetic acid bacteria (AAB) (Acetobacter tropicalis was the dominant species). In both processes, a sequence of substrate consumption (sucrose, glucose, fructose, and citric acid) and metabolite production kinetics (ethanol, lactic acid, and acetic acid) similar to that of previous, larger-scale fermentation experiments was observed. The technological potential of yeast, LAB, and AAB isolates was evaluated using a polyphasic study that included the measurement of stress-tolerant growth and fermentation kinetic parameters in cocoa pulp media. Overall, strains L. fermentum UFLA CHBE8.12 (citric acid fermenting, lactic acid producing, and tolerant to heat, acid, lactic acid, and ethanol), S. cerevisiae UFLA CHYC7.04 (ethanol producing and tolerant to acid, heat, and ethanol), and Acetobacter tropicalis UFLA CHBE16.01 (ethanol and lactic acid oxidizing, acetic acid producing, and tolerant to acid, heat, acetic acid, and ethanol) were selected to form a cocktail starter culture that should lead to better-controlled and more-reliable cocoa bean fermentation processes.     

Combined immobilized cell bioreactor and pulse column technology as a novel approach to food modification

The continuous use of an immobilized cell bioreactor (ICB) and a countercurrent pulse column is a unique approach to removing malic acid from coffee beans prior to roasting. This process recycled a high soluble solids water extract from the green coffee beans through a spiral-wound ICB loaded with food-grade bacteria (Lactobacillus spp. or Leuconostoc spp.) which metabolized malic acid in the green coffee bean extract. The demalated extract was then recirculated to extract the malic acid from the green beans during the countercurrent flow of the ‘malic acid-lean’ extract over the beans. The malic acid level in the beans was reduced by more than 80%. This extract recycle process may have other applications for removing unwanted organics or adding desirable water-soluble components. and is particularly suited to processing beans and grains.     

A novel isolate of <Emphasis Type="Italic">Clostridium butyricum</Emphasis> for efficient butyric acid production by xylose fermentation

Bacterial fermentation of lignocellulose has been regarded as a sustainable approach to butyric acid production. However, the yield of butyric acid is hindered by the conversion efficiency of hydrolysate xylose. A mesophilic alkaline-tolerant strain designated as Clostridium butyricum B10 was isolated by xylose fermentation with acetic and butyric acids as the principal liquid products. To enhance butyric acid production, performance of the strain in batch fermentation was evaluated with various temperatures (20–47 °C), initial pH (5.0–10.0), and xylose concentration (6–20 g/L). The results showed that the optimal temperature, initial pH, and xylose concentration for butyric acid production were 37 °C, 9.0, and 8.00 g/L, respectively. Under the optimal condition, the yield and specific yield of butyric acid reached about 2.58 g/L and 0.36 g/g xylose, respectively, with 75.00% butyric acid in the total volatile fatty acids. As renewable energy, hydrogen was also collected from the xylose fermentation with a yield of about 73.86 mmol/L. The kinetics of growth and product formation indicated that the maximal cell growth rate (μ _m ) and the specific butyric acid yield were 0.1466 h^?1 and 3.6274 g/g cell (dry weight), respectively. The better performance in xylose fermentation showed C. butyricum B10 a potential application in efficient butyric acid production from lignocellulose.     

Purification and Characterization of Antioxidative Peptides Derived From Fermented Milk (<Emphasis Type="Italic">Lassi</Emphasis>) by Lactic Cultures

Fermentation of milk with lactic acid bacteria is the most suitable approach to enrich the bioactive peptides in fermented milk products. So in the present study, two sets of fermented milk (lassi) were prepared. The one lassi was prepared using standard Dahi culture NCDC-167(BD₄) and the other one was made with the same Dahi culture combined with Lactobacillus acidophilus NCDC-15 as an adjunct culture. The preparation steps i.e. preheat treatment and incubation period were optimized by using response surface methodology to obtain maximum antioxidant activity. Lassi prepared with adjunct culture using optimized conditions showed an antioxidant activity of 0.66?±?0.01 µM Trolox/mg protein which was significantly higher than that control (0.22?±?0.01 µM Trolox/mg protein). Out of 59 peptide fragments of β casein fermented by L. acidophilus and 24 peptides from control have been identified by LC–MS/MS. Most of the peptides showed the antioxidant activity. The therapeutic potential of fermented milk products could be improved by increased production of bioactive peptides through controlled fermentation using appropriate proteolytic starter strain.     

Sequential inoculum of <Emphasis Type="Italic">Hanseniaspora guilliermondii</Emphasis> and <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> for winemaking Campanino on an industrial scale

In this study, the effect of sequential inoculation with non-Saccharomyces (Hanseniaspora guilliermondii) and Saccharomyces cerevisiae yeast on the distinctive characteristics of the Campanino white wine was investigated. For this purpose, three independent winemaking experiments were carried out on an industrial scale (batches A, B and C). In detail, the first one was carried out using the sequential inoculation technique while the other two, using a S. cerevisiae single-strain starter or no inoculation representing the control batches. Microbiological and chemical parameters and sensorial profiles of the wines were defined. Interestingly, the results showed that when sequential cultures (H. guilliermondii in a sequential mixture with S. cerevisiae) were used, a better wine aroma and quality was observed. More specifically, the wine obtained by sequential inoculation showed lower acetic acid values and enhanced volatile profiles than the wine from the control batches. Finally, sensorial analysis confirmed that the sequential cultures led to an improvement in wine flavour. Therefore, results suggest that the sequential inoculation using non-Saccharomyces and Saccharomyces yeast represents a biotechnological practice that can improve the quality features of traditional white wine. It has been shown for the first time that on an industrial scale H. guilliermondii could be used in sequential inoculum with S. cerevisiae in making white Campanino wine.

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Structure and diversity of bacterial communities in the fermentation of da-jiang

Da-jiang is the traditional soybean fermented food which is popular in the world for a long time. In order to improve the quality and nutritional value of da-jiang, structure and diversity of bacterial communities in the fermentation of da-jiang were analyzed. Illumina MiSeq platforms coupled with bioinformatics approach were used in this study. In the first 28 days, the trends of bacterial abundance were similar in different regions which are increasing firstly, decreasing secondly, and rising again. The quantity of bacteria in post-fermentation is lower than pre-fermentation. In the fermentation of da-jiang, Firmicutes and Proteobacteria are the dominant phyla. The dominant genera in da-jiang from different regions are different: Tetragenococcus (58.1–73.0%) is the dominant genus in da-jiang from Xinmin; Leuconostoc (9.2–25.7%) is the dominant genus in da-jiang from Tieling; Acinetobacter (8.7–25.1%) and Leuconostoc (12.4–22.0%) are the dominant genera in da-jiang from Shenyang. Additionally, Weissella, Lactobacillus, Staphylococcus, Erwinia, and Pseudomonas also were found in da-jiang. It is identified that Leuconostoc steadily existed in all da-jiang samples. These results demonstrate the diversity of microbes in traditional fermented da-jiang, which will probably provide a data basis for choosing starter culture for da-jiang industrial fermentation.