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Microbial metabolism is important for the unique flavor formation of Mei yu, a kind of traditional Chinese fermented fish pieces. However, the interactive relationship between microorganisms and flavor components during fermentation is still unclear. In this study, electronic nose and headspace-solid-phase microextraction-gas chromatography-mass spectrometry analysis were performed to identify flavor components in Mei yu during the fermentation, and the absolute microbial quantification was conducted to identify the diversity and succession of microbial communities. During fermentation, there was an increase in the types of volatile compounds. Alcohols, aldehydes, aromatics and esters were the main flavor compounds and significantly increased in Mei yu, while hydrocarbon and aldehydes significantly decreased. The absolute abundances of Lactobacillus, Lactococcus and Weissella increased significantly after 3 days' fermentation, which were closely associated with the productions of 1-nonanol, 2-methoxy-4-vinylphenol, guaiacol, ethyl palmitate and ethyl caprylate that might though pathways related to fatty acid biosynthesis and amino acid metabolism. However, these genera were negatively correlated with the production of indole. Additionally, the total volatile basic nitrogen (TVB-N) levels of Mei yu fermented during 3 days were within the limits of 25 mg TVB-N/100 g fish, with the contents of free amino acids and lipoxygenase activities were significant lower than that of 4 days' fermentation. In view of food safety and flavor, it suggested that the natural fermented Mei yu at room temperature should be controlled within 3 days. This study highlights the application of absolute quantification to microbiome analysis in traditional fermented Mei yu and provides new insights into the roles of microorganisms in flavor formation during fermentation.

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Wheat starch fermentation slurry is the main substrate for producing Ganmianpi, a traditional Chinese fermented wheat starch-based noodle. In the present work, the microbial population dynamics and metabolite changes in wheat starch fermentation slurry at different fermentation times (0, 1, 2, 3, and 4 days) were measured by using high-throughput sequencing analysis and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS) methods. The texture and sensory properties of Ganmianpi made from fermented starch slurry are also evaluated. The results showed that Latilactobacillus curvatus and Leuconostoc citreum were the dominant bacteria in wheat starch fermentation slurry, while Saccharomyces cerevisiae and Kazachstania wufongensis were identified as the main species of fungi. With the extension of fermentation time, the reducing sugar content first increased and then decreased, when the titratable acidity content showed an increasing trend, and the nonvolatile acid was significantly higher than the volatile acid. A total of 62 volatile flavor compounds were identified, and the highest content is alcohols, followed by acids. Fermentation significantly reduced the hardness and chewiness of Ganmianpi, and increased its resilience and cohesiveness. Ganmianpi made from fermented starch slurry for two and three days showed a higher sensory score than other samples. The present study is expected to provide a theoretical basis for exploiting the strains with potential for commercial application as starter cultures and quality improvement of Ganmianpi.

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Azolla caroliniana Willd. is an understudied wild edible plant native to the Eastern United States. Other species of Azolla have been used across the world for several thousand years as a livestock feed and as "green manure." The use of Azolla for human consumption is thought to be limited by its high total polyphenolic content (TPC). However, the TPC and nutritional content of A. caroliniana has not been thoroughly studied. We measured TPC and other nutrients before and after cooking methods designed to lower TPC. We found that TPC was 4.26 g gallic acid equivalent (GAE) kg-1 DW in raw A. caroliniana. All cooking methods significantly lowered TPC. Protein content was 19% DW, and the apparent protein digestibility was 78.45%. Our yield was 173 g FW m-2 day-1 and 5.53 g DW m-2 day-1. Azolla caroliniana is a high-yielding plant with great potential for cultivation and domestication.

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This study focused on evaluating the potential of the natural fermentation of pea flour to improve the release of antioxidant compounds. Preliminary fermentations of 36.4% w/w flour dispersions were performed in tubes under different conditions (24 and 48 h, 30 and 37 °C). Finally, fermented flours (FFs) were obtained in a bioreactor under two conditions: 1: 36.4% w/w, 24 h, 30 °C (FF1); 2: 14.3% w/w, 24 h, 37 °C (FF2). The pH values decreased to 4.4-4.7, with a predominance of lactic acid bacteria. As in the fermentations in tubes, an increment in the proteolysis degree (TNBS method) (greater for FF2), polypeptide aggregation and a decrease in their solubility, an increase in <2 kDa peptides, and an increase in the Oxygen Radical Absorption Capacity (ORAC) potency of PBS-soluble fractions after fermentation were demonstrated. Also, fermentation increased the proteolysis degree after simulated gastrointestinal digestion (SGID, COST-INFOGEST) with respect to the non-fermented flour digests, with some differences in the molecular composition of the different digests. ORAC and Hydroxyl Radical Averting Capacity (HORAC) potencies increased in all cases. The digest of FF2 (FF2D) presented the greater ORAC value, with higher activities for >4 kDa, as well as for some fractions in the ranges 2-0.3 kDa and <0.10 kDa. Fermentation also increased the 60%-ethanol-extracted phenolic compounds, mainly flavonoids, and the ORAC activity. After SGID, the flavan-3-ols disappeared, but some phenolic acids increased with respect to the flour. Fermentation in condition 2 was considered the most appropriate to obtain a functional antioxidant ingredient.

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Fermentation plays a crucial role in traditional Chinese mianpi processing, where short-term natural fermentation (within 24 h) is considered advantageous for mianpi production. However, the influence of short-term natural fermentation on the properties of wheat starch is not explored yet. Hence, structural characteristics and paste properties of wheat starch during natural fermentation were investigated in this study. The findings revealed that fermenting for 24 h had a slight effect on the morphology of wheat starch but significantly decreased the particle size of starch. Compared to native wheat starch, the enzyme activity produced during fermentation may destroy the integrity of starch granules, resulting in a lower molecular weight but higher relative crystallinity and orderliness of starch. After 24 h of natural fermentation, higher solubility and swelling power were obtained compared to non-fermentation. Regarding paste properties, fermented starches exhibited higher peak viscosity and breakdown, along with lower final viscosity, tough viscosity, and setback. Furthermore, the hardness, gel strength, G', and G" decreased after fermentation. Clarifying changes in starch during the short-term natural fermentation process could provide theoretical guidance for improving the quality and production of short-term naturally fermented foods such as mianpi, as discussed in this study.

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Chinese sausage is a popular traditional Chinese meat product, but its high-fat content makes consumers hesitant. The purpose of this study is to compare the nutritional differences of Chinese sausages with different fermentation times (0, 10, 20, 30 d) and fat content (the initial content was 11.59% and 20.14%) during digestion. The comparison of digestion degree, protein structure, and peptide composition between different sausages were studied through in vitro simulated digestion. Chinese sausages with high-fat content had higher α-helix, ß-turn, and random coil, making them easier to digest. The fermentation process made this phenomenon more pronounced. The high-fat sausage fermented for 10 d showed the highest release of primary amino acids (about 9.5%), which was about 3.5% higher than the low-fat sausage under the same conditions. The results of peptidomics confirmed the relevant conclusions. After gastric digestion, the types of peptides in the digestive fluid of high-fat sausages were generally more than those in low-fat sausages, while after intestinal digestion, the opposite results were observed. The type of peptide reached its peak after fermentation for 20 d. These findings are of obvious significance for selecting the appropriate fermentation time and fat content of Chinese sausages.

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Vinegar has been used for centuries as a food preservative, flavor enhancer, and medicinal agent. While commonly known for its sour taste and acidic properties due to acetic acid bacteria metabolism, vinegar is also home to a diverse community of lactic acid bacteria (LAB). The main genera found during natural fermentation include Lactobacillus, Lacticaseibacillus, Lentilactobacillus, Limosilactbacillus, Leuconostoc, and Pedicoccus. Many of the reported LAB species fulfill the probiotic criteria set by the World Health Organization (WHO). However, it is crucial to acknowledge that LAB viability undergoes a significant reduction during vinegar fermentation. While containing LAB, none of the analyzed vinegar met the minimum viable amount required for probiotic labeling. To fully unlock the potential of vinegar as a probiotic, investigations should be focused on enhancing LAB viability during vinegar fermentation, identifying strains with probiotic properties, and establishing appropriate dosage and consumption guidelines to ensure functional benefits. Currently, vinegar exhibits substantial potential as a postbiotic product, attributed to the high incidence and growth of LAB in the initial stages of the fermentation process. This review aims to identify critical gaps and address the essential requirements for establishing vinegar as a viable probiotic product. It comprehensively examines various relevant aspects, including vinegar processing, total and LAB diversity, LAB metabolism, the potential health benefits linked to vinegar consumption, and the identification of potential probiotic species.

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BACKGROUND: In recent years, millets are often considered an emerging crop for sustainable agriculture. Therefore, millets can be exploited as an alternative source of starch which has many applications ranging from food, packaging, bioplastics, and others. However, starch is seldom used in its native form and is more often modified to enhance its functional properties. In literature, many traditional millet-based food recipes often incorporate a fermentation step before cooking. Therefore, using this traditional knowledge fermentation has been explored as a potential method for modifying millet starch. RESULTS: Pearl millet (PM) and finger millet (FM) flour were allowed to naturally ferment for 24 h followed by starch extraction. Compared to native (N) starch, water/oil holding capacity and least gelation concentration of fermented (F) starch decreased with no significant change in swelling power. The solubility, paste clarity and in vitro digestibility of starch were significantly affected by fermentation. X-ray diffraction (XRD) data indicates that after fermentation, crystallinity increased while the A-type crystalline structure remained intact. Fourier-transform infrared (FTIR) spectra showed no deletion or addition of any new functional groups. Thermal characterization by differential scanning calorimetry (DSC) showed that the enthalpy of gelatinization of PM starch decreased while that of FM starch increased after fermentation. CONCLUSION: The results indicate that 24 h natural fermentation had a significant impact on functional properties of starch without altering the structural architecture of starch granules. Therefore, fermentation can be further explored as a low-cost alternative for starch modification. © 2023 Society of Chemical Industry.

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Red dragon fruit (RDF) is well-known for its high nutritional content, especially the red pigment betacyanins that possess high antioxidant activity. Natural fermentation is an ancient yet outstanding technique that relies on the autochthonous microbiota from fruits and vegetables surfaces to preserve and improve the nutritional values and quality of the food product. The present study was to evaluate and identify the indigenous microbial community (bacteria and fungi) that are involved in the natural fermentation of RDF. Results revealed a total of twenty bacterial pure cultures and nine fungal pure cultures were successfully isolated from fermented red dragon fruit drink (FRDFD). For the first time, the PCR amplification of 16S rRNA and ITS regions and sequence analysis suggested nine genera of bacteria and three genera of fungi (Aureobasidium pullulans, Clavispora opuntiae, and Talaromyces aurantiacus) present in the FRDFD. Four dominant (≥10 % isolates) bacteria species identified from FRDFD were Klebsiella pneumonia, Brevibacillus parabrevis, Bacillus tequilensis and Bacillus subtilis. The carbohydrate fermentation test showed that all the indigenous microbes identified were able to serve as useful starter culture by fermenting sucrose and glucose, thereby producing acid to lower the pH of FRDFD to around pH 4 for better betacyanins stability. The present study provides a more comprehensive understanding of the indigenous microbial community that serves as the starter culture in the fermentation of RDF. Besides, this study provides a useful guide for future research to be conducted on studying the rare bacterial strains (such as B. tequilensis) identified from the FRDFD for their potential bioactivities and applications in medical treatment and functional foods industries.

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In order to find out the effect of salt concentration on fermented rape stalks, the physicochemical quality and volatile components was investigated using high performance liquid chromatography (HPLC) and headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that there were abundant kinds of free amino acids (FAAs) in all samples, mainly presenting sweet, umami and bitter taste. Through taste activity value (TAV), His, Glu, and Ala contributed significantly to the taste of the sample. 51 volatile components were identified, of which the relative contents of ketones and alcohols were high. By the relative odor activity value (ROAV) analysis, the main components that had a great impact on the flavor were phenylacetaldehyde, ß-Ionone, ethyl palmitate and furanone. Adjusting the appropriate salt concentration for fermentation could improve the comprehensive quality of fermented rape stalks and promote the development and utilization of rape products.

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Due to the uncontrolled fermentation process and unstable quality of naturally fermented leaf mustard, inoculated fermentation is receiving more attention. Here, the physicochemical properties, volatile compounds, and microbial community in leaf mustard under natural fermentation (NF) and inoculated fermentation (IF) were analyzed and compared. The contents of total acid, crude fiber, and nitrite of leaf mustard were measured. Headspace-solid phase microextraction-gas chromatography-mass spectrometry and orthogonal projection on latent structure-discriminant analysis were used to analyze the differences of volatile compounds in NF and IF leaf mustard. Moreover, Illumina MiSeq high-throughput sequencing technology was employed to reveal the composition of microbiota. The results showed that the nitrite content in leaf mustard after IF (3.69 mg/kg) was significantly lower than that after NF (4.43 mg/kg). A total of 31 and 25 kinds of volatile components were identified in IF and NF, respectively. Among the detected compounds, 11 compounds caused the differences between IF and NF leaf mustard. The results of inter-group difference analysis showed that there were significant differences in fungal flora between IF and NF samples. Saccharomycetes, Kazachstania, and Ascomycota were the landmark microorganisms in IF leaf mustard and the landmark microorganisms in NF were Mortierellomycota, Sordariomycetes, and Eurotiomycetes. The abundance of probiotics (such as Lactobacillus) in IF leaf mustard (51.22%) was higher than that in NF (35.20%) and the abundance of harmful molds (such as Mortierella and Aspergillus) was opposite. Therefore, IF leaf mustard showed the potential to reduce the content of nitrite and harmful molds and increase the beneficial volatile compounds and probiotics. PRACTICAL APPLICATION: Leaf mustard of inoculated fermentation (IF) showed better fermented characteristics than natural fermentation in terms of lower nitrite content, greater beneficial volatile substances, and better potential for increasing probiotics and reducing harmful molds. These results provided a theoretical basis for IF leaf mustard and contributed to the industrial production of fermented leaf mustard.

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Mouding sufu, a traditional fermented soybean product in China, has been recognized by the public in the southwestern regions of China. To reveal the microbial community succession and their relationship with the flavor formation during the natural fermentation of Mouding sufu, microbial community, non-volatile flavor compounds and volatile flavor compounds were analyzed by high-throughput sequencing, high-performance liquid chromatography, gas chromatography ion migration spectroscopy, respectively. The results showed that Lactobacillus and Klebsiella were the most abundant bacterial genus, whereas the main fungal genera were unclassified-f-Dipodascaeae and Issatchenkia. In addition, Glutamic acid, Aspartic acid, Alanine, Valine, Lysine, Histidine, lactic acid, succinic acid, and acetic acid were the main non-volatile flavor substances. Furthermore, the taste activity values of glutamic acid, aspartic acid and lactic acid reached 132, 68.9, 18.18 at H60, respectively, meaning that umami and sour were the key taste compounds. Simultaneously, ethyl 3-methylbutanoate-M, ethyl propanoate, methyl 2-methylbutanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate-D, ethyl isobutyrate, linalool-M, linalool-D, cis-4-heptenal, 2-methylpropanal were the characteristic volatile flavor of Mouding sufu. Finally, correlation analysis showed that g__Erwinia and g__Acremonium correlated with most of the key aroma compounds. 20 bacteria and 21 fungi were identified as core functional microbe for Mouding sufu production.

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This work compared the flavor evolution of normal-fat (NF) with that of low-fat (LF) Chinese sausage during natural fermentation. Higher degree of lipid oxidation occurred in NF sausages, resulting in its faster formation of stable volatile profiles. Faster formation of esters occurred in NF sausage in the initial 10 days, whereas prolonged fermentation reduced the level of ethyl lactate-M, ethyl heptanoate, ethyl hexanoate-D and ethyl pentanoate-D. Gradual reduction of alcohols was observed in both groups, and surge in aldehydes occurred in LF samples during day 20-30 period. Faster formation of taste characteristics and larger amount of 2-methylfuran as well as 2,3-dimethylpyrazine were found in LF sausages, since more free amino acids were liberated in LF sausages. Umami and aftertaste tastes formed in the first 20 days, whereas prolonged fermentation reduced these favorable taste. These results highlight that the choice of proper fermentation duration should largely depend on the fat content in Chinese sausages.

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Complex microbial communities contribute significantly to the flavor formation of traditional fermented fish products. However, the relationship between microorganisms and flavor formation in traditional fermented grass carp products is still unclear. In this study, the diversity and succession of microbial communities and the variation of volatile compounds during natural fermentation of grass carp were analyzed using high-throughput sequencing of 16S rRNA and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. The core functional microorganism and key volatile compounds were identified, and their potential relationship was revealed using a correlation network model analysis. The microbial community analysis result showed that the microbial diversity during natural fermentation of grass carp decreased markedly with increasing fermentation time, and Lactiplantibacillus, Staphylococcus, and Enterobacter were the dominant genera in naturally fermented grass carp. HS-SPME-GC-MS analysis result showed that 45 volatile compounds were identified from fermented samples, among which 13 compounds (e.g., hexanal, heptanal, nonanal, decanal, 3-octanone, 3-methyl-1-butanol, 1-hexanol, 1-heptanol, 1-octen-3-ol, 1-octanol, ethyl acetate, 3-methyl-1-butanol acetate, and 2-methoxy-4-vinylphenol) were identified as the key volatile compounds. Additionally, the correlation network model analysis result revealed that Lactiplantibacillus showed significantly positive correlations with most of the key volatile compounds, making an important contribution to the formation of volatile flavor in naturally fermented grass carp. This study may lead to an understanding of the role of core functional microorganisms in the formation of volatile flavor during the natural fermentation of grass carp and provide some theoretical guidance for the industrial production of high-quality fermented grass carp products.

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Alfalfa is harvested two or three times a year in central and western Inner Mongolia, China. However, the variations in bacterial communities as affected by wilting and ensiling, and the ensiling characteristics of alfalfa among the different cuttings, are not fully understood. To enable a more complete evaluation, alfalfa was harvested three times a year. At each time of cutting, alfalfa was harvested at early bloom, wilted for 6 h, and then ensiled in polyethylene bags for 60 days. The bacterial communities and nutritional components of fresh alfalfa(F), wilted alfalfa(W) and ensiled alfalfa(S), and the fermentation quality and functional profile of bacterial communities of the three cuttings alfalfa silage, were then analyzed. Functional characteristics of silage bacterial communities were evaluated according to the Kyoto Encyclopedia of Genes and Genomes. The results showed that all nutritional components, fermentation quality, bacterial communities, carbohydrate, amino acid metabolism and key enzymes of bacterial communities were influenced by cutting time. The species richness of F increased from the first cutting to the third cutting; it was not changed by wilting, but was decreased by ensiling. At phylum level, Proteobacteria were more predominant than other bacteria, followed by Firmicutes (0.063-21.39%) in F and W in the first and second cuttings. Firmicutes (96.66-99.79%) were more predominant than other bacteria, followed by Proteobacteria (0.13-3.19%) in S in the first and second cuttings. Proteobacteria, however, predominated over all other bacteria in F, W, or S in the third cutting. The third-cutting silage showed the highest levels of dry matter, pH and butyric acid (p < 0.05). Higher levels of pH and butyric acid were positively correlated with the most predominant genus in silage, and with Rosenbergiella and Pantoea. The third-cutting silage had the lowest fermentation quality as Proteobacteria were more predominant. This suggested that, compared with the first and second cutting, the third cutting is more likely to result in poorly preserved silage in the region studied.

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Fermented minced peppers are a traditional fermented food that has a unique flavor due to various microbial communities involved in fermentation. Understanding the changes in microbial communities and volatile components of fermented minced peppers is particularly important to unveil the formation of unique flavor of fermented peppers. In this study, the microbial communities and volatile compounds in fermented minced pepper was analyzed by high-throughput sequencing and GC-MS, as well as their underlying correlations were also established. Results indicated that 17 genera were identified as dominant microorganisms in the fermentation of minced pepper, accompanied by the detection of 64 volatile compounds. Further hierarchical clustering analysis (HCA) displayed that dynamic change of volatile metabolites were involved in the fermentation process, where alkane volatile components were mainly generated in the early stage (3-5 days), and alcohols volatile components were in the middle stage (7-17 days), while ester volatile components were mainly produced in both the early stage (3-5 days) and last stage (17-20 days). Bidirectional orthogonal partial least squares (O2PLS) analysis revealed that 11 genera were core functional microorganisms of fermented minced pepper. Cladosporium and Hansenpora were significantly correlated with the formation of 9 and 6 volatiles, respectively. These findings provide new insights into aroma profile variation of fermented minced peppers and underlying mechanism of characteristic aroma formation during fermentation.

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Finger millet is a cereal grain which is superior to wheat and rice in terms of dietary fibre, minerals, and micronutrients. Fermentation is one of the oldest methods of food processing, and it has been used to ferment cereal grains such as finger millet (FM) for centuries. The aim of this study was to investigate the impact of spontaneous fermentation (SF) on mineral content, functional, thermo-pasting, and microstructural properties of light- and dark-brown FM flours. Spontaneous fermentation exhibited a significant increase in the macro-minerals and micro-minerals of FM flours. In terms of functional properties, SF decreased the packed bulk density and swelling capacity, and it increased the water/oil absorption capacity of both FM flours. Spontaneous fermentation had no effect on the cold paste viscosity of FM flours. However, significant decreases from 421.61 to 265.33 cP and 320.67 to 253.67 cP were observed in the cooked paste viscosity of light- and dark-brown FM flours, respectively. Moreover, SF induced alterations in the thermal properties of FM flours as increments in gelatinisation temperatures and gelatinisation enthalpy were observed. The results of pasting properties exhibited the low peak viscosities (1709.67 and 2695.67 cP), through viscosities (1349.67 and 2480.33 cP), and final viscosities (1616.33 and 2754.67 cP), along with high breakdown viscosities (360.00 and 215.33 cP) and setback viscosity (349.33 and 274.33 cP), of spontaneously fermented FM flours. Scanning electron microscopy showed that SF influenced changes in the microstructural properties of FM flours. The changes induced by SF in FM flours suggest that flours can be used in the food industry to produce weaning foods, jelly foods, and gluten-free products that are rich in minerals.

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The 'Kyoho' grape (Vitaceae, Plantae) has large ears, plenty of flesh, and rich nutrition and is planted across a large area in China. There are few reports on this variety in winemaking, especially on the dynamic changes of fungi in the wine fermentation broth. In this study, we used the 'Kyoho' grapes as raw materials and adopted a high throughput to analyze dynamic changes in fungal species composition of the natural fermentation broth at four time points: day 1 (D1P), day 3 (D3P), day 5 (D5P), and day 15 (D15P). Changes in fungal metabolic pathways and dominant yeasts were also analyzed. A total of 78 families, 110 genera, and 137 species were detected, in the natural fermentation broth samples. Forty-nine families, 60 genera, and 72 species were found in the control check (CK). A total of 66 differential metabolic pathways were enriched; of those, 41 were up-regulated compared to CK, such as CDP-diacylglycerol biosynthesis I (PWY 5667), chitin degradation to ethanol (PWY 7118), and the super pathway of phosphatidate biosynthesis (PWY 7411). Changes in fungal metabolic pathways were in line with the dynamic changes of dominant yeast species in the whole process of fermentation. Pichia kluyveri, P. membranifaciens, and Citeromyces matritensis are the dominant species in the later stages of natural fermentation. These yeast species may play vital roles in the 'Kyoho' wine industry in the future.

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Suansun is a typical fermented bamboo shoot product widely consumed in southern China. Complex microorganisms are involved during spontaneous fermentation of suansun. However, little is known about the succession and roles of these microbiota throughout the fermentation process, especially for the functional microbiota involved in aroma formation. Thus, in this study, the dynamic changes in physicochemical parameters, flavor compounds, and microbiota community during the natural production of suansun were investigated. The principal component analysis (PCA) results showed that physicochemical parameters and flavor compounds varied substantially during the 30-day fermentation. Moreover, the microbial flora exhibited a dynamic change from the acid-sensitive genera of Lactococcus, Leuconostoc, Weissella, and Enterobacter to an acid-resistant genus of Lactobacillus due to lactic acid and acetic acid accumulation. Furthermore, bidirectional orthogonal partial least squares (O2PLS) indicated that four bacterial genera, namely, Lactobacillus, Clostridium_sensu_stricto_1, Enterobacter, and Leuconostoc, showed strong connections with various characteristic flavors, thus playing crucial roles in the unique flavor formation of suansun. These results may shed light on the development of effective starter cultures for the industrial manufacture of high-quality suansun products.

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The effect of fermentation treatment on the surface morphology, crystal structure, molecular weight, chain length distribution, and physicochemical properties of corn starch was investigated using natural fermentation of corn ballast. The amylose content in corn ballast starch reduced at first after natural fermentation, then grew, following the same trend as solubility. There were certain erosion marks on the surfaces of fermented corn ballast starch granules. The crystalline structure of corn ballast starch remained the same, i.e., a typical A-type crystalline structure, at different fermentation times; however, the intensities of diffraction peaks were different. The weight-average molecular weight of starch first increased and then decreased after fermentation. The content of low-molecular-weight starch (peak 3) decreased from 25.59 to 24.7% and then increased to 25.76%, while the content of high-molecular-weight starch (peak 1) increased from 51.45 to 53.26%, and then decreased to 52.52%. The fermentation time showed a negative correlation with the viscosity of starch, and the pasting temperature first increased, and then decreased. Natural fermentation can be used as a technical means to produce corn starch products as a result of the experiments' findings, and future experiments will detect and analyze the bacterial structure of corn fermentation broth in order to better understand the molecular mechanism of natural fermentation affecting the structure and physicochemical properties of corn starch.