Abstract:As a non-thermal sterilization technology, ultra-high pressure sterilization can protect the thermosensitive nutrients and maintain the texture of food, demonstrating unique technical advantages in the processing of prepared dishes. By a review of domestic and foreign literature and performance of relevant equipment, this paper introduced the principle, equipment, and parameters of ultra-high pressure sterilization. Considering the parameters of ultra-high pressure sterilization and the effects of food ingredients on the pressure tolerance of different microbial species, the factors affecting the effect of ultra-high pressure sterilization were analyzed. In addition, the effects of ultra-high pressure sterilization on the physical and chemical properties, sensory quality, enzyme activity, microorganisms count and bioactive substances of prepared dishes were summarized. Finally, the problems and solutions of the current application of ultra-high pressure sterilization in the processing of prepared dishes were pointed out. The review aims to provide reference for the application of ultra-high pressure sterilization in the prepared dish industry.

Abstract:Tea polyphenols are the general term for polyphenols in tea, mainly including catechins, flavonoids, and anthocyanins, which have antioxidant and antimicrobial properties. The author reviewed the structural characteristics and the antioxidant and antibacterial mechanisms of tea polyphenols. Additionally, the application of tea polyphenols in the processing and preservation of meat products is summarized, providing a theoretical basis for their use in meat products. Studies have shown that tea polyphenols can achieve anti-oxidation by scavenging free radicals, chelating metal ions, and inhibiting oxidase activity. Moreover, tea polyphenols can inhibit cell growth and proliferation by inhibiting the activities of enzymes involved in cell metabolism and damaging the cell membrane system. As natural antioxidants, tea polyphenols can significantly prolong the shelf life of meat products and are widely used in fresh, pre-made, sauced, pickled, and other meat products. At present, the mechanisms underpinning the antibacterial and antioxidant effects of tea polyphenols in meat products have not been fully clarified, and the poor solubility and low stability of tea polyphenols remain to be solved. Future research should focus on the modification and optimization of tea polyphenols, synergistic preservation, and the application of tea polyphenols in meat processing to further improve the preservation effect.

Abstract:The widespread abuse of traditional antibiotics has led to the emergence and development of antimicrobial peptides due to the resultant bacterial resistance. Antimicrobial peptides demonstrate high efficacy in combating infectious pathogens and possess unique antimicrobial mechanisms and biocompatibility, effectively reducing the bacterial resistance rate. The high structural adaptability endows antimicrobial peptides with multiple biological activities, enabling targeted action against diverse types of pathogens and abnormal cells. Accordingly, antimicrobial peptides exhibit a promising development prospect. Enhanced stability contributes to prolonging the in vivo half-life and improving the bioavailability of antimicrobial peptides, which holds crucial importance for improving the clinical translation value of antimicrobial peptides. The author summarizes the research progress in antimicrobial peptides regarding the biological activities, mechanisms of action, and applications in food, agriculture, and medical fields. Furthermore, the author discusses the low stability of antimicrobial peptides in applications and the approaches to enhance their stability and makes an outlook on future research directions and application prospects for antimicrobial peptides.

Abstract:[Objective] This study aims to investigate the effects of steaming-drying cycles on the quality changes of Polygonati rhizoma and optimize the processing technology to enhance its application value.[Method] Slices of Polygonati rhizoma processed by 0~5 steaming-drying cycles were prepared. The drying rate and drying kinetics during the drying stage after each cycle were analyzed, and a drying model was fitted. Changes in color difference, appearance, hardness, and mass fractions of polysaccharides, reducing sugars, polyphenols, flavonoids, saponins, and calcium oxalate raphides were measured.[Result] The number of steaming-drying cycles significantly affected the quality of Polygonati rhizoma. The drying rate decreased as the drying time increased, conforming to the Modified Page model, while the water activity reduced. As the number of steaming-drying cycles increased, the sample microstructure was disrupted, which promoted the release of active substances. The mass fractions of saponins, flavonoids, and polyphenols in the C4 group increased by 161.28%, 67.15%, and 417.93%, respectively, compared with those in the C0 group. Non-enzymatic browning reactions led to increased color difference and significantly decreased mass fraction of calcium oxalate raphides, which reduced oral irritation. Although the mass fraction of polysaccharides declined during processing, the C4 group exhibited 5.15% higher polysaccharide retention rate and 141.63% lower hardness than the C5 group.[Conclusion] The processing with steaming-drying cycles significantly improves the quality of Polygonati rhizoma. The processing method of four steaming-drying cycles demonstrates outstanding performance in releasing active substances, preserving polysaccharides, and controlling hardness, showing broad application prospects.

Abstract:[Objective] This study determined the mold count, total plate count, and osmophilic yeast count in Apis cerana honey and explored the correlations of osmophilic yeasts with quality parameters and storage conditions of the honey.[Method] A total of 105 Apis cerana honey samples were used for the determination of mold count, total plate count, and osmophilic yeast count, as well as odor, moisture, phenolic acids, and carbohydrates. The correlations between quality indexes and osmophilic yeasts and the effects of different storage conditions on osmophilic yeast count were explored.[Result] Among the 105 samples, 1, 1, and 67 samples showed the mold count, total plate count, and osmophilic yeast count exceeding the national standards. All the samples with osmophilic yeast count exceeding the national standard had a peculiar smell, and their moisture mass fractions were all higher than 18.54%. The mass fractions of moisture and glycerol had correlations with osmophilic yeast count (P<0.01), and the mass fractions of phenolic acids, fructose, and glucose were correlated with osmophilic yeast count (P<0.05). Different storage temperatures affected the growth of osmophilic yeasts in the samples. At lower storage temperatures (4~7 ℃ and 15~20 ℃), the growth of osmophilic yeasts was slow, while at higher storage temperatures (29~38 ℃), the osmophilic yeast count showed an upward trend to exceed the national standard.[Conclusion] This study provides an important reference for the quality evaluation and quality control of Apis cerana honey.

Abstract:[Objective] The aim of this study is to synthesize aminated glycogen (NG) for loading of the photosensitizer TTVBA and construct a nano drug delivery system (NGT NPs) for photodynamic therapy (PDT) of tumors. [Method] Positively charged NG was synthesized through modification of glycogen with diethylenetriamine (DETA). Then, TTVBA was encapsulated by NG via electrostatic interaction to prepare NGT NPs. The prepared NGT NPs were characterized by infrared spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The hemolysis assay was performed to evaluate the biocompatibility of NGT NPs. The reactive oxygen species (ROS) generation capability of cells treated with NGT NPs was detected with the DCFH-DA probe. The in vitro antitumor activity of NGT NPs was assessed by the CCK-8 assay and AM/PI staining. [Result] NGT NPs were spherical, with the diameter of 104.8 nm and the surface potential of 23.83 mV. The ROS generated by the cells treated with NGT NPs (20 μg/mL) under light was 12 folds of that in the dark. The NGT NPs group possessed a hemolysis rate below 0.41%, which indicated excellent biocompatibility. In B16 cells under light, NGT NPs raised the ROS level ( P<0.001) while reducing the cell survival rate in a mass concentration-dependent manner. AM/PI staining showed more cell death in the light group than in the control group. [Conclusion] NGT NPs possessed good biocompatibility, light-responsive induction of ROS generation, and antitumor activity. This work provides a novel and efficient nanocarrier for the PDT of tumors.

Abstract:[Objective] This study aims to prepare a highly specific antibody against channelrhodopsin-1 (ChR1) from Chlamydomonas reinhardtii (C. reinhardtii) and investigate its regulatory mechanisms in cellular phototaxis and negative phototaxis.[Method] The recombinant expression vector pET-28a(+)-chr1 was constructed and transformed into Escherichia coli (E. coli) BL21 (DE3) competent cells. The expression of the fusion protein 6×His∷ChR1 was induced with IPTG, and the obtained protein was purified by nickel-affinity chromatography. The purified protein was used to immunize New Zealand white rabbits for the production of ChR1 antiserum. ChR1-specific IgG antibodies were enriched from the antiserum through protein A purification. The antibody specificity was assessed by immunoblotting, and the subcellular localization of ChR1 was analyzed by immunofluorescence.[Result] The results of indirect ELISA indicated that the ChR1 antiserum had a titer of 1∶102 400. Immunoblotting with the purified ChR1 antibody identified a distinct band corresponding to endogenous ChR1 in CC-125 cells, with no nonspecific band observed, thereby confirming the high specificity of the antibody. Immunofluorescence staining revealed clear localization of ChR1 at the eyespot and specific staining, demonstrating the suitability of the antibody for immunofluorescence assays.[Conclusion] The prokaryotic expression, purification, and polyclonal antibody preparation of ChR1 were achieved. This study lays a crucial foundation for delving into the localization of ChR1 in C. reinhardtii and the molecular regulatory mechanisms of ChR1 in phototaxis and negative phototaxis.

Abstract:[Objective] This study aims to enhance the high osmotic pressure tolerance of Escherichia coli (E. coli) for the efficient production of succinic acid.[Method] Adaptive evolution, transcriptomic analysis, reverse metabolic engineering, and fermentation optimization were employed for improving E. coli tolerance to high osmotic pressure.[Result] By analyzing the key factors influencing succinic acid production by fermentation, osmotic pressure was identified as the critical factor reducing succinic acid production efficiency . A mutant strain, E. coli FN-6, with tolerance to high osmotic pressure was obtained through adaptive evolution. The key gene cusC responsible for osmotic pressure tolerance was identified by transcriptomic analysis. After optimization of the expression level of cusC, the engineered strain E. coli FN-20 showed strong tolerance to high osmotic pressure. In a 5 L fermenter with E. coli FN-20, the succinic acid titer, yield, and productivity were up to 145.27 g/L, 90.0%, and 2.01 g/(L·h), respectively.[Conclusion] The obtained E. coli FN-20 strain with tolerance to high osmotic pressure enabled efficient production of succinic acid. This provides a new approach for the industrial production of succinic acid and provides the reference for producing other high value-added chemicals by fermentation.

Abstract:[Objective] The physiological characteristics vary greatly among different strains of Tetragenococcus halophilus (T.halophilus). By comparing some indicators of safety properties, growth characteristics, and fermentation performance of T. halophilus strains from different sources, the authors aim to establish a regular understanding of this bacterial species.[Method] Seventeen strains of T. halophilus derived from different aquatic products and soy sauce mash were selected, and their antibiotic resistance, biogenic amine production, hemolytic activity, growth under different environmental conditions, and flavor characteristics after fermenting soybean hydrolysate were determined. Additionally, correlation analysis was conducted to identify the associations among various indicators.[Result] In terms of safety properties, the 17 strains were generally sensitive to penicillin, vancomycin, and tetracycline, but resistant to trimethoprim-sulfamethoxazole, streptomycin, and clindamycin, with strains from the same source showing similar results in antibiotic tests. All the strains commonly produced tyramine and cadaverine, and a few strains produced spermidine and histamine. Histamine-producing strains all originated from shrimp paste and pickled fish. None of the strains exhibited hemolytic activity. In terms of growth characteristics, all the strains grew slowly under conditions of 25 g/dL NaCl, pH 5, and 15 ℃, while their growth rates gradually recovered after the stress conditions were alleviated, with most strains showing the optimal growth temperatures between 30 ℃ and 37 ℃. Glucose at low concentrations promoted the growth of strains, while as the glucose concentration increased, the growth rates of some strains decreased. All the strains could grow under anaerobic conditions. Factor analysis was performed to comprehensively assess the growth of the 17 strains, and the results showed that strains from sauce mash had higher scores, indicating their strong environmental adaptability. In terms of fermentation performance, all the strains improved the flavor and nutritional value of soybean hydrolysate, increasing the mass concentrations of total acids (TA), amino acid nitrogen (AAN), and TCA-soluble peptides after fermentation. Correlation analysis revealed that the growth ability of T. halophilus was positively correlated with its acid production but negatively correlated with AAN and biogenic amine production.[Conclusion] The safety properties, growth characteristics, and fermentation performance of T. halophilus have certain correlations with the strain sources. These findings provide a theoretical basis and reference for gradually establishing a regular understanding of T. halophilus.

Abstract:[Objective] The aim of this study is to evaluate and improve the antioxidant effects of natural antioxidants and their derivatives on anchovy (Engraulis japonicus) oil.[Method] The 60 ℃ accelerated oxidation model was used to evaluate the antioxidant effects of phytic acid, tea polyphenols (TP), rosemary extract, ascorbyl palmitate, vitamin E, tea polyphenol palmitate (TPP), and bamboo leaf extract on anchovy oil based on the peroxide value (POV), thiobarbituric acid reactive substances (TBARS) value, relative intensity of free radicals, and fatty acid composition.[Result] TPP (single antioxidant) and TPP+TP (composite antioxidant) demonstrated the strongest antioxidant effects on anchovy oil.[Conclusion] Although the antioxidant effect of TPP+TP is slightly weaker than that of TPP, because of the lower price of TP, the production cost during anchovy oil processing and storage can be effectively reduced by the combination of TPP and TP. The findings are of great significance to the actual production of anchovy oil and its products.

Abstract:[Objective] This study aims to improve the detection specificity and sensitivity for Escherichia coli (E. coli) O157:H7.[Method] A highly specific and sensitive method for the detection of E. coli O157:H7 was established based on magnetic separation and signal amplification strategies combined with surface-enhanced Raman spectroscopy (SERS). Aptamers were used as recognition elements and combined with magnetic beads and polystyrene (PS) microspheres to construct a separation probe (MB@Apt) and a signal amplification Raman tag (4-MBN@PS@Apt), respectively.[Result] In the presence of E. coli O157:H7, MB@Apt and 4-MBN@PS@Apt formed a “sandwich” structured composite (MB@Apt/E. coli O157:H7/4-MBN@PS@Apt), which could be rapidly separated and enriched by an external magnet. After tetrahydrofuran (THF) was added, the low biological background Raman reporter 4-MBN in the Raman tag was quickly released. The relative Raman intensity of 4-MBN at 1 073.9 cm^-1 showed a good linear relationship with the logarithm of E. coli O157:H7 concentration in the range of 1×10³ to 1×10⁸ CFU/mL, with a determination coefficient (R²) of 0.98. The established method showed a limit of detection (LOD) of 312 CFU/mL for E. coli O157:H7, the recovery rates ranging from 61.87% to 135.55% in tap water and milk samples, and relative standard deviations (RSD) between 0.27% and 5.28%.[Conclusion] This method exhibited high detection sensitivity for E. coli O157:H7 and provided a new approach for rapid detection of foodborne pathogenic bacteria.

Abstract:[Objective] A fluorescent immunochromatographic assay was established based on vitamin B₁ monoclonal antibody to measure the vitamin B₁ in infant formula milk powder.[Method] The performance of vitamin B₁ monoclonal antibody was evaluated. On this basis, a highly sensitive fluorescent immunochromatographic test strip was developed.[Result] The vitamin B₁ monoclonal antibody showed high sensitivity, affinity, and specificity. The fluorescent immunochromatographic test strip showed a visual limit of detection (vLOD) of 10 μg/kg, a cut-off value of 200 μg/kg, and a calculated limit of detection (cLOD) of 2.056 μg/kg. In addition, the recovery rate of this method was 97.3%~115.4%. The test results of the established method were consistent with the liquid chromatography-tandem mass spectrometry (LC-MS/MS) results, with the relative standard deviation (RSD) less than 10%, which indicated good accuracy and stability.[Conclusion] The fluorescent immunochromatographic assay can be used for the rapid detection of actual infant formula milk powder samples. It does not require large-scale instruments or equipment and is portable, thus being of great significance for the rapid screening of a large number of samples.

Abstract:[Objective] A colloidal carbon-labelled immunochromatographic assay with competitive inhibition was developed for the detection of marbofloxacin (MBF) residues in milk powder and chicken.[Method] The anti-MBF polyclonal antibody prepared in the author's laboratory was employed to produce the colloidal carbon-labelled immunoprobe. The effects of pH of reaction system, resuspension solution, treatment solution of sample pad, standard dilution buffer, mass concentration of colloidal carbon, mass concentration of primary antibody, mass concentration of coating antigen, and mass concentration of secondary antibody on the MBF colloidal carbon-labelled immunochromatographic assay were investigated. The sensitivity, specificity, stability, and accuracy of the method were determined.[Result] Under optimal conditions, the cut-off value of the method was 4.0 ng/mL,which was five times higher than the value of traditional colloidal gold-labelled immunochromatographic assay. The semi-quantitative detection limit was 0.4 ng/mL. The method showed good specificity for the detection of MBF and could be stored at room temperature for 16 weeks. The spiked recovery results in milk powder and chicken samples were basically consistent with those of ultra-high performance liquid chromatography coupled with a fluorescence detector.[Conclusion] The established method is simple, sensitive, specific, and stable, and thus it can be utilized for rapid detection of MBF residues in animal-derived foods.

Abstract:[Objective] This study aims to analyze the characteristics of volatile aroma components and key aroma components of black tea samples from different tea varieties in Guangxi.[Method] The aroma components of 12 black tea samples from Guangxi were identified by sensory quality evaluation, headspace solid-phase microextraction-gas chromatography-mass spectrometry（HS-SPME-GC-MS）, hierarchical cluster analysis, and orthogonal partial least squares-discrimination analysis (OPLS-DA).[Result] The black tea samples from different tea varieties showed different aroma characteristics and mainly presented a floral fruity aroma or a sweet aroma. The black tea from ‘Wuniuzao’ demonstrated the highest comprehensive score (91.20), being a representative of black tea with a sweet aroma, followed by ‘Huangguanyin’ (with a comprehensive score of 90.55), which was a representative of black tea with a floral fruity aroma. A total of 40 aroma components were detected in 12 black tea samples, including alcohols, aldehydes, ketones, esters, olefins, pyrroles and their derivatives, and other aroma components. Among them, alcohols, esters, and aldehydes were the main aroma contributors, with the relative content of 59.84%~79.21%, 4.21%~17.68%, and 2.93%~13.64%, respectively. An OPLS-DA model, which enabled the effective distinguishing of black tea samples with a floral fruity aroma and a sweet aroma, was constructed based on the relative content of 33 common aroma components. Dehydrolinalool, linalool oxide Ⅱ, linalool oxide Ⅰ, geraniol, methyl salicylate, (E)-2-hexenal, linalool, and β-ionone were identified as the key differential aroma components between black tea samples with the two aromas.[Conclusion] The black tea samples from different tea varieties in Guangxi have a floral fruity aroma or a sweet aroma. The findings provide a theoretical basis for the recognition of tea aroma characteristics and the development of characteristic black tea.

Abstract:[Objective] This study explored the structural characteristics and in vitro antioxidant activity of yam polysaccharide-selenium nanoparticle (YP-SeNPs) complexes.[Method] Yam polysaccharide (YP) were obtained through hot water extraction and then purified by purification, diethylaminoethyl cellulose 52 (DEAE-52) column chromatography, and dialysis. With YP as a template, YP-SeNPs were prepared with different Se/YP mass ratios (1∶3, 1∶1, and 4∶3) in an oxidation-reduction system comprising ascorbic acid (VC) and sodium selenite (Na₂SeO₃）. The complexes were characterized via multiple techniques, including visual observation of solution color, ultraviolet-visible absorption (UV-vis) spectroscopy, particle size measurement, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The in vitro antioxidant activity of YP-SeNPs was evaluated by measuring the scavenging ability against 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) free radicals.[Result] YP-SeNPs were successfully constructed, exhibiting spherical morphology and containing C, O, and Se elements. The optimal Se/YP mass ratio was determined to be 1∶3, yielding the smallest particle size of (61.67±0.69) nm. The complexes demonstrated high stability. YP effectively prevented the aggregation and sedimentation of SeNPs, thereby improving the dispersion of the complexes. YP-SeNPs exhibited good scavenging capacity against DPPH and ABTS free radicals, with the maximum scavenging rates of (96.66±0.79)% and (96.66±1.19)%, respectively.[Conclusion] YP-SeNPs have good antioxidant activity and can be developed and utilized as a functional antioxidant.

Abstract:[Objective] A simple and sensitive detection method for Staphylococcus aureus is established for the efficient detection of this pathogen in food.[Method] Targeting Staphylococcus aureus, a simple and sensitive fluorescent detection method for Staphylococcus aureus, EXPAR-P-AgNCs, was developed based on exponential amplification reaction (EXPAR) combined with DNA silver nanoclusters (P-AgNCs). A recognition probe was designed to initiate EXPAR in the presence of Staphylococcus aureus, generating a large amount of target DNA(T). The binding of T to hairpin P displaced the G-rich strand from P-AgNCs, resulting in a decrease in the relative fluorescence intensity of P-AgNCs and enabling the detection of Staphylococcus aureus.[Result] The relative fluorescence intensity showed a good linear relationship with Staphylococcus aureus concentration in the range of 1×102 and 1×10? CFU/mL. The limit of detection was as low as 10 CFU/mL. The method shows high specificity without cross-reactions. The recovery rates for Staphylococcus aureus spiked in milk and pork samples ranged from 94.5% to 115.0%.[Conclusion] The developed detection method demonstrates high sensitivity and excellent specificity, offering a promising approach for the detection of microbial pathogens or other contaminants threatening food safety.

Abstract:[Objective] This study aims to prepare γ-aminobutyric acid (GABA)-enriched milk fermented with lactic acid bacteria and evaluate its anti-exercise fatigue effect.[Method] High GABA-producing lactic acid bacteria were selected and used to ferment milk with a commercial starter culture. A mouse model of exercise fatigue was established by four weeks of exhaustive swimming training. After four weeks, the exhaustive swimming time, serum biochemical indicators, antioxidant indicators, and energy storage substance levels were measured and analyzed.[Result] Lactobacillus plantarum (L. plantarum) LP-5 was selected as the strain for fermentation, and its GABA yield reached (1.340±0.003) g/L. The fermented milk showed the titratable acidity of (46.29±2.01) oT, the colony count of 2.18×10⁹ CFU/mL, and the GABA mass concentration of (1.780±0.011) g/L. Compared with that at the initial fermentation, the fermented milk showed increased content of various free amino acids (P<0.05). Differences were observed in the fatigue-related indicators between the control and model groups (P<0.01). Compared with the model group, the commercial starter culture group and the commercial starter culture + L. plantarum LP-5 group exhibited increases in swimming exhaustion time (P<0.01) and decreases in activities of creatine kinase and lactate dehydrogenase in the serum, mass concentration of blood lactate, and concentration of blood urea nitrogen (P<0.01). In addition, the two groups showcased increased activity of superoxide dismutase (P<0.01), decreased concentration of malondialdehyde (P<0.01), and increased mass fractions of glycogen in the liver and muscle (P<0.01). Moreover, the commercial starter culture + L. plantarum LP-5 group showed better anti-fatigue effects.[Conclusion] The GABA-enriched milk fermented with lactic acid bacteria has significant anti-exercise fatigue effects in mice, with the commercial starter culture + L. plantarum LP-5 group showing the most significant effect.

Abstract:[Objective] This study aims to explore the physicochemical indicators, microbial diversity, and volatile substances in the Qupi (surface) and Quxin (core) of high-temperature Daqu.[Method] High-throughput sequencing and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) were employed to compare the microbial diversity, volatile substances, and physicochemical indicators between Qupi and Quxin of three types of Daqu.[Result] The moisture mass fraction in Qupi of the three types of Daqu was lower than that in Quxin (P<0.05), and the moisture mass fraction was the lowest in the Qupi of white Daqu (WP) and the highest in the Quxin of yellow Daqu (YX). The acidity of Qupi and Quxin were in the order of Quxin of black Daqu (BX) > YX > Qupi of black Daqu (BP) > Quxin of white Daqu (WX) > Qupi of yellow Daqu (YP) > WP. High-throughput sequencing results showed that Firmicutes and Proteobacteria were the dominant bacterial phyla, and Ascomycota was the dominant fungal phylum in Daqu. At the genus level, Pseudomonas_E was the dominant bacterial phyla in BP, BX, and YX; Blastococus was the dominant bacterial phyla in WP; and Scopulibacillus was the dominant bacterial phyla in WX. Thermomyces was the dominant fungal genus in all the samples, while its relative abundance varied among samples. In addition, the microbial diversity in Qupi of Jiangxiangxing high-temperature Daqu was higher than that in Quxin. The redundancy analysis (RDA) results indicated that moisture content and temperature were positively correlated with WP, and YX and BX were positively correlated with acidity. The microbial community structure difference between Qupi and Quxin was mainly attributed to the micro-ecosystem difference. The quantitative analysis results of 76 volatile substances in Qupi and Quxin showed that among esters, the mass fraction of ethyl acetate in WP was relatively high; among aldehydes, the mass fraction of benzaldehyde in BX was relatively high; among acids, isovaleric acid has the highest mass fraction in WX; among pyrazines, tetramethyl pyrazine has the highest mass fraction in WX. The results indicated the mass fractions of volatile substances were different in Qupi and Quxin of different types of Daqu.[Conclusion] This study provides a theoretical foundation for further research on the evolution of microbial communities and the mechanism of volatile substances in Jiangxiangxing high-temperature Daqu.