Solid-state pure culture is a biotechnology that simulates the natural fermentation environment. It uses solid matrix such as rice, bran, soybean meal as the growth medium for industrial microorganisms to ferment and produce by single microbial strain under sterile conditions. Compared with liquid fermentation, its fermentation conditions are stricter, but it can improve the quality and yield of the product. In this paper, the types and principles of different solid-state fermentation reactors suitable for pure culture were introduced, the factors (temperature and heat transfer process, ventilation and mass transfer process, sterilization and inoculation process, and the water content and pH of the material) affecting the solid-state fermentation effect were summarized, the application of solid-state pure culture technology in fermented foods was elaborated, and the future research prospects of solid-state fermentation reactors were expected.

Fungal laccase is a simple, efficient, energy-saving, and environmentally friendly green biocatalyst, which has extremely important application potential and commercial value in the field of food processing and wastewater treatment. Using O₂ as a substrate, these enzymes induce single electron transfer of phenolic and non-phenolic compounds to produce water as the only by-product. At present, lignin in food and agricultural waste can be effectively oxidized and cleaved with laccase obtained by macrofungi fermentation culture, reducing energy consumption and cost. In addition, the laccase produced during the fermentation process can be recovered and recycled for application in food processing and wastewater treatment. The methods of producing fungal laccase from food industry by-products and agricultural waste were summarized, the latest research progress on the application of fungal laccase in improving the quality of fruit juice, wine, beer, bread and pectin gelation in food processing, as well as the treatment of food wastewater from wineries and olive oil plants were primarily highlighted, in order to provide theoretical basis and scientific guidance for expanding the application of fungal laccase in the field of food industry and environmental remediation.

The antioxidant properties of glutathione significantly affect the formation of aroma during the fruit wine fermentation process, and it is also a precursor to the synthesis of mercaptan aroma compounds, which can be used as an essential substance for modulating and enhancing the aroma of fruit wine. The dual roles of glutathione as a "substrate" and "enzyme-promoted" agent during the aroma-enhancing fermentation process of fruit wine were reviewed, and the protective and regulatory mechanisms of glutathione on key aroma components in fruit wine were reviewed. Furthermore, the positive effects of Saccharomyces cerevisiae, non-Saccharomyces cerevisiae, glutathione-enriched inactive dry yeast and live yeast cell derivative on aroma compounds under the regulation of glutathione were discussed, aiming to provide a theoretical basis and reference for further research on enhancing the aroma of fruit wine with glutathione.

Caproic acid bacteria are functional microorganisms that produce caproic acid in pit mud, and caproic acid is the precursor of ethyl caproate, a characteristic flavor compound of strong-flavor (Nongxiangxing) Baijiu. Therefore, caproic acid bacteria are crucial in the production of strong-flavor Baijiu. In this paper, the sources of caproic acid bacteria production in pit mud, caproic acid synthetic metabolic pathways, and the relationship between pit mud quality indicators and caproic acid bacteria were briefly introduced. The application of caproic acid bacteria in new artificial pit mud and pit mud maintenance was mainly elaborated. The research aims to maintain the balance of microecology inside the pit mud, meet the needs of pit mud maintenance, and improve the quality of Baijiu.

Chinese Baijiu is unique among the world alcoholic drinks because of its unique production technology and liquor body style, in which multi- strains fermentation is the main technological feature different from other distilled liquors. As an important microorganism in the brewing process of Baijiu, Bacillus has an extremely important influence on the flavor and quality of liquor. The species, diversity, functional characteristics, and the application of functional Bacillus in Baijiu brewing process were summarized, and the future research direction of Bacillus was prospected, aiming to provide theoretical reference for the application of Bacillus in Baijiu production, which was of great significance for Baijiu quality improvement production.

In this study, using an ester-producing strain Wickerhamomyces anomalus C11 as the research object, the stress tolerance of the strain was studied by plate growth method. The whole-genome of W. anomalus C11 was sequenced with Illumina second-generation sequencing technology, and the functional genes were annotated and analyzed using clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and carbohydrate active enzymes (CAZy) database. The pathogenicity was analyzed based on the pathogen-host interaction (PHI) database. The results demonstrated that W. anomalus C11 exhibited good environmental tolerance to multiple stress conditions, including 100 g/L NaCl, 25 mmol/L H₂O₂ , 500 mmol/L mannitol, pH 3.0-10.0, low temperature (16 ℃), high temperature (37 ℃), and 40 mmol/L Pb. The W. anomalus C11 genome had a total length of 11.48 Mbp, GC content of 34.42%, and encoded 4 249 genes. The W. anomalus C11 genome was annotated to 1 641, 3 346 and 3 145 functional genes from the COG, GO and KEGG databases, respectively. Additionally, the genome harbored 32 glycoside hydrolase- related genes and 39 glycosyltransferase-related genes, which could contribute to its ester-producing capacity and stress tolerance. Virulence gene prediction identified 676 virulence-attenuated genes, 391 non-virulent genes, 134 avirulent genes, 84 lethal genes, and 39 hypervirulent genes, further confirming W. anomalus C11 had low virulence and high safety.

In this study, the in vitro antioxidant activity of free peptides in distiller's grains of strong-flavor (Nongxiangxing) Baijiu was determined by measuring the free radical scavenging rate of 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH). The cyclic peptides in the free peptides were identified using high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry (HPLC-Q-TOF-MS), and the anti-oxidative stress action mechanism of cyclic peptides was studied using network pharmacology combined with molecular docking methods. The results showed that the content of cyclic dipeptides in distiller's grains was 30.20 mg/g, and the half maximal inhibitory concentration (IC₅₀) value of DPPH radicals was 2.30 mg/ml, which had a certain in vitro antioxidant capacity. A total of 19 cyclic peptides were isolated and identified from the distiller's grains extract, including 10 cyclic dipeptides, 2 cyclic tripeptides, 7 cyclic peptide ethyl esters. Among them, 8 cyclic dipeptides were involved in 274 core targets related to antioxidant effects, including 8 key core targets. All 8 cyclic dipeptides and 8 key core targets could form stable complexes through intermolecular forces, and exerted anti-oxidative stress effects through multi-target and multi-pathway, mainly involved in apoptosis, cancer, calcium regulation, inflammation and other biological processes.

In order to investigate the quality differences of base liquor produced from fermented grains in different spatial locations of sauce-flavor (Jiangxiangxing) Baijiu pit, the volatile components in the base liquor of the fourth-round sauce-flavor Baijiu were quantitatively analyzed using gas chromatography-flame ionization detection (GC-FID), and the differences in volatile flavor components of the base liquor produced from different spatial positions of the fermented grains were analyzed by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The contribution of different compounds to the aroma characteristics of the base liquor was evaluated by combining the aroma activity value (OAV). The PCA results showed that the three types of base liquors produced from the fermented grains of surface, middle, and bottom pit were well distinguished. 12 differential compounds were screened by OPLS-DA combined with variable importance projection (VIP) values, including ethyl caproate, n-propanol, and ethyl acetate. Combining the aroma activity value (OAV>1, VIP>1), it was found that ethyl caproate and ethyl butyrate contribute greatly to the flavor of base liquor produced from the fermented grains of bottom pit. The correlation analysis between differential compounds and aroma characteristics showed that acetic acid, octanoic acid, and ethyl acetate were significantly and extremely significantly positively correlated with floral and fruity aromas (P<0.05, P<0.01), while they were significantly or extremely significantly negatively correlated with cellar aroma and sauce aroma (P<0.05, P<0.01); Furfural, butyric acid, hexanoic acid, etc. were significantly positively correlated with Quxiang (P<0.01), while they were significantly negatively correlated with Liangxiang (P<0.01). This study provided a basis for understanding the aroma difference of base liquor produced by fermented grains at different locations in the pits, and laid a foundation for exploring the fermentation mechanism of sauce-flavor Baijiu pits.

In this study, using Illumina high-throughput sequencing, diversity analysis, and principal coordinate analysis (PCoA), the physicochemical properties and microbial community structure of Huangshui from new (one-year-old) and old pits (over 10 years and over 20 years old) in Qionglai production area were compared. The results revealed that the concentrations of acetic acid, propionic acid, lactic acid, and caproic acid in the Huangshui from the old pits were significantly higher than those from the new pit (P<0.05). Additionally, the contents of reducing sugar and starch in the Huangshui from the old pits increased significantly with the age of the pits (P<0.05). As the pit age increased, the richness and diversity of bacterial communities in the Huangshui of both the new and old pits gradually decreased, while the fungal communities initially decreased and then increased. The Huangshui of different pits ages could be distinguished by PCoA. Lactobacillus and Microascus were the dominant genera in the new pit, while Lactobacillus and Thermoascus were the dominant genera in the old pits. Lactobacillus showed a significant positive correlation with the contents of lactic acid, reducing sugar, and starch (P<0.01), suggesting that Lactobacillus might be the key genus influencing the differences in Huangshui across pit ages and in the fermentation system of Baijiu. Moreover, the fungal genera Monascus and Penicillium were positively correlated with lactic acid, caproic acid, reducing sugar, and starch contents. These findings indicated that changes of pit age had an important effect on the formation of microbial community and its metabolites in the Huangshui.

To explore the regulatory role of Rhizopus in brewing, the culturable experiment was carried out with Rhizopus delemar. The effects of medium moisture and temperature on the spore proliferation, amylase activity, and volatile flavor compound production were studied. The model was constructed by orthogonal partial least squares discriminant analysis (OPLS-DA), and key volatile flavor compounds were screened based on variable importance in projection (VIP) values and analysis of variance P value. The results showed that moisture 45% was beneficial for R. delemar spore propagation and amylase production. The highest spore counts were (139.28±5.94)×10⁶ spores/g at 25 ℃. The highest amylase activity was (126.09±4.33) U/g at 30 ℃. The moisture 30% and temperature 40 ℃ were the optimal for the accumulation of volatile flavor substances. 36 volatile flavor compounds were added after wheat substrate was inoculated with R. delemar, and 11 key differential volatile flavor compounds (VIP>1, P<0.05) were screened out, including benzyl alcohol, heptyl acetate, methoxybenzoxime, ethyl myristate, ethanol, butyl acetate, ethyl hexanoate, ethyl acetate, ethyl octanoate, and 1-nonanol.

The substance composition of sauce-flavor (Jiangxiangxing) Baijiu samples (numbered as 5y, 10y, 20y, 35y and 60y) with different aging years (5 year, 10 year, 20 year, 35 year and 60 year) were analyzed through non-targeted metabolomics, and the different substances of sauce-flavor Baijiu with different aging years were explored by principal component analysis (PCA) combined with orthogonal partial least squares-discriminant analysis (OPLS-DA) multivariate statistical analysis. The results showed that a total of 89 volatile compounds were detected from sauce-flavor Baijiu with different aging years by headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS), mainly ethyl palmitate, ethyl hexanoate, and ethyl phenylacetate, and the longer the aging year, the more volatile compounds. There were 17, 21, 17 and 17 main differential volatile compounds among samples of 5y and 10y, 10y and 20y, 20y and 35y, 35y and 60y, respectively. A total of 1 292 non-volatile compounds in sauce-flavor Baijiu with different aging years were detected by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC- MS/MS), and there were 28, 24, 13 and 21 main differential non-volatile compounds among samples of 5y and 10y, 10y and 20y, 20y and 35y, 35y and 60y, respectively, mainly amino acids, fatty acids, organic acids, and aromatic compounds, such as heptanedioic acid, azelaic acid, mannitol, conjugated linoleic acid and so on. These findings revealed the changing law of the composition of sauce-flavor Baijiu with different aging years, and provided a scientific basis for seeking a reasonable aging time of sauce-flavor Baijiu.

Litchi (Litchi chinensis Sonn.) fruit wine was prepared using fresh litchi as material, and the fermentation process was optimized by single factor and response surface tests using sensory scores as response value. The volatile flavor components and non-volatile metabolites in litchi fruit wine before and after fermentation were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and liquid chromatography-mass spectrometry (LC-MS). The model was constructed using orthogonal partial least squares discriminant analysis (OPLS- DA), the key differential metabolites were screened by variable importance in projection (VIP) and P values, and the metabolic pathways were analyzed. The results showed that the optimal fermentation process was obtained as follows: fermentation temperature 28 ℃, yeast inoculum 2.5%, initial pH 5.0, and initial reducing sugar content 180 g/L. Under these optimal conditions, the alcohol content and sensory score of litchi fruit wine were 15.64%vol and 92.0 points, respectively. A total of 10 organic acids were detected in litchi fruit wine, and a total of 56 volatile flavor compounds were detected in litchi fruit wine before and after fermentation, including 21 alcohols, 12 esters, 2 aldehydes, 3 acids, 8 alkenes and 10 others. A total of 544 key differential metabolites (VIP≥1, P<0.05) were screened from litchi fruit wine before and after fermentation, of which 334 were up-regulated and 210 were down-regulated. The results of KEGG pathway enrichment analysis showed that the metabolites such as fenugreek and L-malic acid were significantly enriched after fermentation and had potential health care functions, and amino acid biosynthesis pathways played an important role in the formation of characteristic flavors.

In order to screen specific yeast strains for sour cherry fruit wine, using naturally fermented sour cherry juice as experimental material, the yeast strains were isolated and screened using traditional culture and separation technology in conjunction with morphological observation. The superior yeast strains were subsequently screened by fermentation performance test and ethanol production capacity test, identified by molecular biology technology, and their tolerance was analyzed. The results indicated that a total of 34 yeast strains were isolated and screened from the naturally fermented sour cherry juice. Among them, 6 superior yeast strains exhibiting rapid gas production and high ethanol production ability were screened, and numbered as FC2, FC3, FC11, FC14, FC16 and FC18, respectively. After identification, the strains FC2 and FC11 were identified as Saccharomyces cerevisiae, while the remaining strains were identified as Hanseniaspora uvarum. All 6 strains could tolerance ethanol volume fraction 16, pH 2.6 and glucose mass concentration 400 g/L, and the strains FC2, FC11 and FC16 exhibited superior tolerance compared to strains FC3, FC14 and FC18. These study results could provide some references for sour cherry fruit wine brewing.

In this study, using a strain tz-6 with antagonistic effect on Staphylococcus aureus as the research object, the strain tz-6 was identified by morphological observation, physiological and biochemical tests and 16S rDNA sequence analysis, and the effects of the strain tz-6 on the growth of S. aureus, β-galactosidase, deoxyribonucleic acid (DNA) and protein leakage degree, cell membrane formation and pyruvate release were investigated to explore its antibacterial mechanism. The results showed that strain tz-6 was identified as Streptomyces sp., the fermentation crude extract of strain tz-6 could damage the membrane and internal structure of S. aureus, increase the membrane permeability, leading to acidic substances and β-galactosidase release, enhance nucleic acid and protein content in bacterial supernatant, and hinder the body energy and material metabolism in S. aureus.

In order to investigate the microbial community structure in the Daqu and fermented grains at the later stages of fermentation for strong-flavor (Nongxiangxing) and light-flavor (Qingxiangxing) Baijiu, analyze the similarities and differences in microbial communities between the two types of Baijiu production, the microbial community structure in Daqu and fermented grains was analyzed by high-throughput sequencing technology. The results showed that the richness and diversity of bacteria were significantly higher than that of fungi in both flavor type of Daqu and fermented grains. There were two specific strains in strong-flavor Daqu. At the bacterial genus level, the relative abundance of Weissella in strong-flavor Daqu was much higher than that in light-flavor Daqu (23% and <1%, respectively), while the relative abundance of Pantoea was lower than that of light-flavor Daqu. The relative abundance of Acetobacter in the fermented grains of strong-flavor Baijiu was the highest, the relative abundance of Lactiplantibacillus in fermented grains of light-flavor Baijiu was the highest. At the fungal genus level, the relative abundance of Pichia and Saccharomyces in Daqu and fermented grains of strong-flavor Baijiu were the highest, respectively. The relative abundance of Saccharomycodes and Saccharomyces in Daqu and fermented grains of light-flavor Baijiu were the highest, respectively. The relative abundance of Pichia in strong-flavor Daqu (66%) was much higher than that in light-flavor Daqu (2%). The difference of community abundance in strong-flavor Daqu was larger, while the difference of community abundance in light-flavor Daqu was balanced. Saccharomyces was the most abundant genus in both flavor types of fermented grains. The relative abundance of Aspergillus in the fermented grains of strong-flavor Baijiu (6%) was lower than that in light-flavor Baijiu (18%), while the relative abundance of Naumovozyma (20%) was higher than that in light-flavor Baijiu (1%). These findings provided a theoretical basis for clarifying the formation mechanism of Baijiu flavor types and the cultivation and screening of functional microorganisms.

To obtain Monascus spp. with high efficiency in degrading pit bottom wastewater from sauce-flavor (Jiangxiangxing) Baijiu production, Monascus strains were screened from sauce-flavor Baijiu Daqu using traditional cultivation methods and identified through morphological observation and molecular biology techniques. The growth capacity of Monascus was evaluated with biomass. The degradation of organic pollutants and the effects of fermentation pit bottom wastewater on lovastatin and γ-aminobutyric acid production of screened strains were investigated, and the synthesis mechanism of high value-added metabolites was analyzed. The results showed that the isolated strains HSHM, AKHM, ZSHM and CMHM were identified as Monascus ruber, Monascus anka, Monascus purpureus, and Monascus pilosus, respectively. Strain ZSHM exhibited the highest biomass (0.098±0.016 g/L) and achieved removal rates of 56.76% biochemical oxygen demand (BOD₅) and 67.63% chemical oxygen demand (COD_cr) indextrose broth medium supplemented with 10% (V/V) pit bottom wastewater. When strain ZSHM was fermented in rice and sorghum substrates, the yields of lovastatin and γ-aminobutyric acid were (23.26±2.08) mg/100 g, (34.27±0.29) mg/100 g and (53.67±0.74) mg/100 g, and (43.66±0.75) mg/100 g, respectively. After adding pit bottom wastewater 10% (V/V) to rice and sorghum substrate, lovastatin yield were significantly reduced to (16.56±0.71) mg/100 g and (35.16±2.08) mg/100 g (P<0.05), and γ-aminobutyric acid yield were significantly increased to (42.58±1.68) mg/100 g and (57.12±1.31) mg/100 g (P<0.05). Transcriptomic analysis revealed that pit bottom wastewater enriched γ-aminobutyric acid by significantly up-regulating genes expression of GAD, GDH2, ALDH, and aofH.

In this study, the sensory characteristics and bacterial community structure of low-temperature Daqu from Liangshan region of Shandong province were determined using electronic nose and electronic tongue technology and MiSeq high-throughput sequencing technology, and the correlation was analyzed. Compared with the bacterial community of low-temperature Daqu in Xiangyang region, Bacillus strains were isolated and identified by pure cultivation and molecular biology techniques. The results showed that the volatile aroma components of Liangshan low-temperature Daqu mainly comprised sulfides, ethanol, and aldehydes/ketones, saltiness and umami tastes were prominent, while sourness and umami aftertastes were weak. The dominant bacterial genera were mainly Pediococcus (25.33%), Weissella (21.58%), and Companilactobacillus (5.27%). Pediococcus, Lactiplantibacillus, and Levilactobacillus showed a significant positive correlation with bitterness or bitter aftertaste (P<0.05). Compared to Xiangyang low-temperature Daqu, the bacterial community richness in Liangshan low-temperature Daqu was lower, with less Bacillus and more lactic acid bacteria, and the common bacterial groups included Bacillus, Kroppenstedtia, and some lactic acid bacteria. A total of 8 strains of Bacillus were isolated and identified from Liangshan low-temperature Daqu, including 3 strains of Bacillus licheniformis, 2 strains of Bacillus sonorensis, 2 strains of Bacillus paralicheniformis, and 1 strain of Bacillus haynesii.

In this study, the diversity of fungal flora of medium-high temperature brick-shaped Daqu and Baobao Daqu from Songhe region was deeply analyzed using high-throughput sequencing technology, and the basic physicochemical properties were detected, aiming to explore the correlation between their physicochemical indexes and fungal community. The results showed that there were 58 operational taxonomic units (OTU) belonging to 3 phyla, 8 classes, 10 orders, 20 families and 30 genera. The α-diversity index values of the two species were similar, the structure of the flora was similar, but the average relative abundance was different. The common dominant fungal genera (relative abundance>1%) were Issatchenkia, Rhizopus, Candida, Wickerhamomyces, Rhizomucor, Torulaspora, and Lichtheimia, Aspergillus and Alternaria were the unique dominant fungi in Baobao Daqu and brick-shaped Daqu, respectively. The moisture, starch content and saccharifying power of brick-shaped Daqu were higher, and the acidity, fermentation power and esterification power of Baobao Daqu were higher. Among them, there were significant differences in moisture, acidity, saccharifying power, fermentation power and esterification power (P<0.05). Correlation analysis results showed that the physiochemical characteristics of Daqu had different effects on fungal community, and the effect of saccharification and esterification power on fungal community structure was particularly significant.

In this study, using Congo red staining method and enzyme activity assay, the high-yield cellulase fungi from soil samples in Turpan area was screened. The screened strain was identified by morphological observation and molecular biology techniques, and the enzymatic characteristics of cellulase produced by the strain were studied. The results showed that a high-yield cellulase fungi 12-3-6 was obtained, and the activity of filter paper enzyme (FPA) and carboxymethyl cellulase (CMCase) in the fermentation broth of the fungi were 7.30 U/ml and 39.56 U/ml, respectively. Strain 12-3-6 was identified as Aspergillus egyptiacus. The results of enzymatic characteristic analysis showed that the optimal reaction conditions of FPA and CMCase produced by strain 12-3-6 fermentation was both reaction temperature 50 ℃ and reaction pH value 5.0. The relative enzyme activity of FPA and CMCase produced by strain 12-3-6 fermentation was still higher after 1 h at 30-60 ℃ or pH 5.0-6.0, and Cu²⁺ could significantly improve the enzyme activity. Sodium dodecyl sulfate (SDS) had a certain inhibitory effect on enzyme activity. The results indicated that the cellulase produced by strain 12-3-6 had high activity and stable enzymatic properties, and had a good application prospect.

Using the Hongyingzi sorghum from Renhuai Guizhou, Qianxi Guizhou, and Ezhou Hubei as the research object, the physicochemical indicators were detected by conventional detection methods, and its metabolites were analyzed by using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) non-target metabolomics technology, the orthogonal partial least squares-discriminant analysis (OPLS-DA) and cluster analysis (CA) were performed based on the results, and the metabolites with significant differences were screened in combination with the variable importance in projection (VIP) value and variance analysis P value (VIP>1, P<0.05). The results showed that there was certain difference in the physicochemical indicators of Hongyingzi sorghum from different regions. The 1 000-grain weight, starch, protein, and tannin contents were 21.24-21.86 g, 65.13%-69.64%, 10.03%-11.01%, and 1.44%-1.60%, respectively. A total of 455 metabolites and 187 significantly different metabolites were identified in the Hongyingzi sorghum from different regions. The results of cluster analysis for the first 25 significantly different metabolites showed that they mainly contained phenolic compounds, organic heterocycles, terpenoids, and amino acids, etc. The contents of phenolic acids, flavonoids and amino acids in Hongyingzi sorghum from different regions related to the Baijiu brewing varied significantly. The contents of phenolic acids, flavonoids and amino acids in Hongyingzi sorghum from Renhuai Guizhou was relatively high, which was more suitable for sauce-flavor (Jiangxiangxing) Baijiu brewing.

Acetoin-producing Bacillus were screened from the fermented grains of sauce-flavor (Jiangxiangxing) Baijiu. The strains were identified through morphological observation and molecular biology techniques. Using uninoculated fermented grains as a control, the selected strains were inoculated into a solid-state fermentation system of fermented grains at different fermentation time (12 h, 24 h, 48 h), to investigate the effects of different inoculation time on the physicochemical indexes, organic acid content, and volatile flavor compounds during fermentation. The results showed that an acetoin-producing strain YH403 was isolated and identified as Bacillus amyloliquefaciens. The fermentation performance of fermented grains of strain YH403 inoculated at 24 h was significantly improved. Compared with the blank group without inoculation, the pH value, water content and reducing sugar content of fermented grains of strain YH403 inoculated at 24 h were improved, which promoted the synthesis of L-lactic acid, acetic acid, succinic acid, citric acid and L-malic acid in fermented grains. The contents of total volatile flavor substances in fermented grains of strain YH403 inoculated at 24 h were significantly increased, especially the contents of esters, pyrazines, alcohols and acetoin were significantly increased, and the contents of acetoin in fermented grains of strain YH403 inoculated at 24 h were twice that of the blank group. Moreover, the synthesis stability of volatile flavor substances was also enhanced.

To investigate the differences in bacterial community structure between high- and medium-high-temperature Daqu, the bacterial community structure of the two types of Daqu was analyzed by third-generation sequencing technology, the correlation between bacterial community and gene functions of bacterial community were analyzed, and the strains were isolated and identified by microbial pure culture and molecular biology techniques. The results showed that the dominant bacterial phyla (average relative abundance>1%) in two types of Daqu included Firmicutes, and the dominant bacterial genera included Kroppenstedtia, and the dominant bacterial species included Kroppenstedtia eburnea. Principal coordinates analysis (PCoA) and linear discriminant analysis effect size (LEfSe) analysis results showed that there were significant differences in the bacterial community structure between the two types of Daqu, with Thermoactinomycetaceae and Dietziaceae as biomarkers for high- and medium-high-temperature Daqu, respectively. Correlation analysis results indicated that the bacterial community in medium-high-temperature Daqu exhibited higher stability. Functional prediction results showed that medium-high temperature Daqu had significantly higher average relative abundance in three functions: carbohydrate transport and metabolism, cell wall/membrane biosynthesis, and cellular motility and signal transduction mechanisms, compared to high- temperature Daqu. A total of 114 strains, belonging to 9 genera and 17 species, were isolated and identified from the two types of Daqu samples, mainly Bacillus licheniformis.

In order to study the application potential of Meyerozyma caribbica in dry red wine fermentation, using 'Cabernet Sauvignon' grapes as raw materials, and the wine was brewed by M. caribbica and Saccharomyces cerevisiae with single fermentation (CK, MC), simultaneous fermentation (TS1, TS2, TS3) and sequential fermentation (SX1, SX2). The physicochemical indexes, volatile flavor components and sensory quality of wine samples were analyzed. The results showed that the quality of mixed fermented wine sample inoculated with M. caribbica for 72 h and then inoculated with S. cerevisiae (SX2) was better, the alcohol content was 12.00%vol, the total acid content was 4.57 g/L, and the anthocyanin content was the highest (468.23 mg/L). A total of 25 volatile flavor components were detected, including 9 esters, 7 alcohols, 4 acids, 3 aldehydes and ketones, and 2 others, and the total contents of volatile flavor components were the highest (3 322.01 μg/L). The key flavor volatile components (odor activity value (OAV)>1) were ethyl caproate, hexyl acetate, ethyl heptanoate, ethyl decanoate, and ethyl caprylate, etc. The results of principal component analysis (PCA) showed that different samples could be distinguished based on volatile flavor compounds with OAV>0.1. The results of sensory evaluation showed that the sensory score of wine sample SX2 was the highest (83.67 points), with typical flavor.

In order to explore the effects of Rhizopus addition on the quality of Xiaoqu light-flavor (Qingxiangxing) Baijiu, the effects of different Rhizopus addition on the enzymatic activity and physicochemical factors of fermented grains, and the flavor components in the base liquor were analyzed by conventional analysis, gas chromatography and high performance liquid chromatography. The results demonstrated that Rhizopus addition predominantly affected enzymatic activities during the saccharification stage. With only Jiuqu addition 1% and no Rhizopus as the control group, when the Rhizopus addition was 0.5%, the saccharification enzyme activity (31.31 U/g) was significantly higher than that of control group (16.94 U/g) (P<0.05). The activity of acid protease (11.09 U/g) was significantly higher than that of control group (6.26 U/g) (P<0.05). The activity of liquefaction enzyme (0.38 U/g) was higher than that of control group (0.35 U/g), but not significant (P>0.05). When the Rhizopus addition was 0.5%, compared with the control group, the contents of acidity, residual sugar, amino acid nitrogen and ammonia nitrogen in fermented grains were the highest at the beginning of fermentation, which were increased by 18.43%, 14.31%, 14.24% and 47.98%, respectively. Additionally, with the Rhizopus increased, the ethyl acetate content in the base liquor gradually increased. By the end of fermentation (15 d), compared to the control group, the ethyl acetate content in the liquor sample with Rhizopus addition 0.5% had increased by 67.84%. In conclusion, Rhizopus addition 0.5% had the optimal effect. This study provided new insights for enriching the flavor profile of liquor and improving the quality of Xiaoqu light-flavor Baijiu.

In this study, the succession rule of fungal community during high-temperature Daqu fermentation was studied by Illumina MiSeq sequencing technology. The α-diversity analysis showed that the richness and diversity of the fungal community increased first and then decreased during high- temperature Daqu fermentation, and the species number (369.16) and Simpson index (0.75) reached the highest at the time of the second Fanqu, and were highly significantly higher than that at the time of Chaiqu (P<0.01). The dominant fungal genera during Daqu fermentation included Thermoascus, Thermomyces, Aspergillus, Rasamsonia, and Byssochlamys. The β diversity analysis confirmed highly significant changes in fungal community structure during fermentation. Linear discriminant analysis effect size (LEfSe) analysis showed that different fermentation stages presented characteristic dominant bacteria, and Phialosimplex, Thermoascus and Thermomyces could be biomarkers of the first Fanqu, second Fanqu and Chaiqu stages, respectively. Correlation analysis showed that changes in fungal community structure might be closely related to inter-species interactions. These findings laid foundation for future optimization of the Daqu fermentation process and improvement of product quality.

In order to understand the distillation rules of higher fatty acids and their ethyl esters in the distillation and aging process of strong-flavor (Nongxiangxing) Baijiu, and the effect of palmitic acid on Baijiu flavor was explored, the higher fatty acids and their ethyl esters in the distillation and aging process was detected by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that the higher fatty acids contents were positively correlated with the distillation process, especially in the late distillation period. The contents of high fatty acid ethyl ester decreased first and then increased. Linoleic acid, stearic acid, palmitic acid and its ethyl ester and ethyl laurate were identified as the key markers to distinguish strong-flavor Baijiu with different aging years. During the aging, the contents of linoleic acid, stearic acid and ethyl palmitate decreased significantly in 8-year aged liquor, indicating that spontaneous esterification and ester volatilization co-acted. In addition, palmitic acid (50 mg/L) inhibited the volatilization of ethyl caproate by 30%, thus affecting Baijiu flavor.

In order to study the driving factors of bacterial community succession during the fermentation process of fresh chili sauce, the changes of bacterial community diversity and physicochemical indicators during the fermentation process of fresh chili sauce were detected respectively by high-throughput sequencing technology and conventional analytical methods, and the interaction between bacterial community succession and endogenous environmental factors changes were revealed by multivariate statistical analysis. The results showed that the reducing sugar contents and pH gradually decreased, and the contents of total acid and amino acid nitrogen shown a trend of stabilizing after rising. The diversity and richness of bacterial communities showed a decreasing trend. Lactobacillus were the absolutely dominant bacterial genus during the fermentation of fresh chili sauce, and its relative abundance increased from 4.48% to 54.67%. There were 27 marker differential bacterial genera during the fermentation process of fresh chili sauce. The results of correlation analysis showed that there were some differences in the interaction between different endogenous environmental factors and dominant bacteria genus, and multiple endogenous environmental factors jointly drove bacterial community succession during the fermentation of fresh chili sauce. Among them, Lactobacillus was extremely significantly positive correlated with the contents of total acid and amino acid nitrogen (P<0.01), and extremely significantly negative correlated with reducing sugar contents and pH (P<0.01). This study provided a theoretical basis for precise artificial regulation during the fermentation of fresh chili sauce.

Using seven kinds of soybean (SB1-SB7) as raw materials, a soy sauce was brewed by high-salt dilute-state technology. The basic physicochemical indexes, free amino acids and free fatty acids composition of the soybean were determined, and the sensory quality, physicochemical indexes, volatile flavor components and non-volatile taste substances of the soy sauce samples were analyzed. The results showed that the physicochemical indexes, free amino acid contents, free fatty acid ratio of 7 different soybeans were different to some extent. SB1, SB2 and SB7 soy sauce samples had better sensory scores (7.86, 7.89 and 8.01 points, respectively). Among them, SB7 soy sauce sample had better comprehensive quality, with higher contents of amino acid nitrogen, reducing sugar and total acid (0.86%, 4.08% and 1.59%, respectively), and the free amino acid and total organic acid contents were highest (30.32 mg/ml and 118.73 mg/ml, respectively). The types of volatile flavor components were the most (50 kinds), and the total contents were the highest (213.2 mg/ml), which was mainly reflected in the higher alcohols and furans (36.86 mg/ml and 11.92 mg/ml, respectively). The sensory score was 8.01, showing the characteristics of delicious and soft, with a strong flavor of sauce and ester.

In order to save the culture time and raw materials of single strain Fuqu, simplify the preparation process of Fuqu, and improve the production efficiency of Fuqu, a mixed-strain Fuqu was prepared using Saccharomycopsis fibuligera and Rhizopus spp. With saccharification power and viable yeast cell counts as evaluation indexes, the preparation process conditions were optimized through single-factor and orthogonal experiments. The mixed-strain Fuqu was applied to the brewing of light-flavor (Qingxiangxing) Baijiu. The physicochemical indexes and changes of volatile flavor substances during the fermentation process of light-flavor Baijiu were studied by conventional detection methods and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) method, and the effect of mixed-strain Fuqu addition on the flavor of light-flavor Baijiu was investigated. The results showed that the optimal preparation process conditions for the mixed-strain Fuqu were as follows: culture temperature 30 ℃, moisture 45%, and cultivation time 36 h. Under these optimal conditions, the saccharification power was 582 U/g, and the viable yeast cell counts were 8.42×10⁸ CFU/g. The mixed-strain Fuqu was applied to light-flavor Baijiu brewing, using commercial Fuqu as the control group, the mixed-strain Fuqu significantly increased the acidity of the fermented grains (P<0.05) and enhanced the contents of ethyl acetate and ethyl lactate, which were 1 798.43 mg/L and 666.91 mg/L, respectively. The results showed that the application of mixed-strain Fuqu in the light-flavor Baijiu brewing could increase the contents of main flavor substances and simplify the Fuqu-making process, providing a new idea for light-flavor Baijiu Jiuqu production.

In order to improve the quality of yogurt during storage and prolong the shelf-life of yogurt, using traditional fermented yogurt as the control group, the Lactobacillus bulgaricus L-14 was substituted for Lactobacillus paracasei ALAC-4 with a broad-spectrum inhibition effect, good fermentation performance, and no antagonism to Streptococcus thermophilus L-1, and was used to ferment yogurt with inoculation 1∶1 (experimental group). The effect of L. paracasei ALAC-4 on the quality of yogurt during storage was explored by determining physicochemical indexes, texture, microbiological indexes, flavor, and sensory evaluation of yogurt in two groups during storage (0-28 d) after fermentation. The results showed that L. paracasei ALAC-4 instead of L. bulgaricus L-14 could delay the decline of sensory scores, water holding capacity, viscosity, post-acidification and flavor quality during the storage period (0-28 d), inhibit the growth of fungi, and prolong the shelf-life, but the effect on the texture was small. After 28 d of storage, the sensory score of yogurt in the experimental group was 82.61, the pH, titratable acidity, water holding capacity, and viscosity were 4.6, 117 °T, 73.33% and 2 622.35 mPa·s, respectively, and the elasticity, resilience, gelatinization, hardness, cohesion and chewiness were 2.73, 0.018, 1.955 N, 10.445 N, 0.188 and 0.537 N, respectively. The logarithmic value of viable Lactococcus and Lactobacillus counts was 8.5 and 8.6, respectively during sealed storage at room temperature, no molds and yeasts were detected, and the flavor quality was good.

In order to broaden the market of Baijiu, meet the needs of young consumers, and solve the problems of traditional low alcohol Baijiu such as thin liquor body and turbidity, light loss and precipitation in the process of alcohol reduction, the ultra-low alcohol strong-flavor (Nongxiangxing) Baijiu was produced by turbidity removal treatment with alcohol activated carbon adsorption and filtration. On the basis of single factor tests, a 4 factors 3 levels response surface tests were conducted using Box-Behnken central composite design. Using the activated carbon addition, activated carbon pores mesh number, standing adsorption time and temperature as the influencing factors, the effects of various factors on the transmittance and sensory score of ultra-low alcohol strong-flavor Baijiu were explored, and the turbidity removal process of ultra-low alcohol strong-flavor Baijiu was optimized. The results showed that when the alcohol reduction of strong-flavor Baijiu was less than 25%vol, the optimal turbidity removal process conditions for ultra-low alcohol strong-flavor Baijiu by activated carbon were as follows: activated carbon pores mesh number 400 mesh, activated carbon addition 0.54‰, static adsorption temperature 5 ℃, and time 20.3 h. Under these optimal conditions, the transmittance and sensory score of ultra-low alcohol strong-flavor Baijiu were 92% and 87 points, respectively.

Using highland barley as the raw material and Bacillus amyloliquefaciens B-14 as the fermentation strain, 1-deoxynojirimycin (DNJ) was produced with solid-state fermentation. The optimal process parameters for the solid-state fermentation of DNJ were optimized through single-factor and response surface experiments. The in vitro hypoglycemic activity was investigated by measuring α-glucosidase, α-amylase, and conducting in vitro digestion experiments. The results indicated that the optimal process parameters for DNJ production by solid-state fermentation of highland barley with B. amyloliquefaciens were fermentation time 3 d, cooking time 41 min, temperature 37 ℃, and inoculum 5.5%. Under these optimized conditions, the DNJ content reached 6.13 mg/g. The half-maximal inhibitory concentration (IC₅₀) values for α-glucosidase and α-amylase were 0.29 mg/ml and 2.89 mg/ml, respectively. In the in vitro digestion experiments, as the addition of the solid-state fermented highland barley product increased, the starch hydrolysis rate showed significantly inhibitory effect. When the addition was 20%, simulated intestinal digestion time was 180 min, the starch hydrolysis rate was 35.13%, indicating that the highland barley fermentation products had a significant effect on reducing blood sugar levels, which provided a reference for the research and development of functional foods based on barley.

In this study, lactic acid bacteria with high-yield protease was isolated and screened from feces of breastfed infants within 6 months of age by hydrolytic ring preliminary screening and protease rescreening. The screened strains were identified by morphological observation, physiological and biochemical tests and molecular biology techniques. The protease production conditions were optimized by single factor test, Plackett-Burman test, steepest climbing tests and response surface tests using protease as evaluation index. The results showed that a strain mys-01 with high-yield protease capacity was obtained and identified as Lacticaseibacillus rhamnosus. The optimal conditions for protease production of Lacticaseibacillus rhamnosus mys-01 were fermentation temperature 38 ℃, time 24 h, initial pH 6, whey powder addition 4%, inoculum 8.5%, malt extract addition 3%. Under the optimized conditions, the protease activity was 70.59 U/ml, which was 84.07% higher than before optimization.

To improve the utilization rate of tea by-products, tea-flavor distilled liquor was prepared by traditional solid-state fermentation using fresh malt and green tea stems as mixed fermentation raw materials. Using sensory score and ethyl acetate content as evaluation indices, the fermentation process was optimized based on single factor tests and central combination design (CCD) tests as well as artificial neural network (ANN) analysis combined with genetic algorithm, and the volatile aroma components of the liquor samples were determined by gas chromatography-mass spectrometry (GC-MS). The results showed that the optimal fermentation conditions were green tea stems addition 7%, cooked grain moisture 52%, Jiuqu addition 0.7%, fermentation time 7 d, and temperature 25 ℃. Under the optimized conditions, the ethyl acetate content of the tea-flavor distilled liquor was 0.46 g/L, the sensory score was 86.67 points, and the alcohol content was 55%vol. A total of 31 volatile flavor compounds were detected based on GC-MS, including 5 alcohols, 16 esters, 5 aldehydes and 5 others. Esters had the highest content, accounting for 52% of all flavor compounds. Tea-flavor distilled liquor possessed robust tea aroma, agreeable mellow taste and distinctive flavor, which served to enhance the character of the tea liquors to a notable degree.

Taking a strain of propionic acid-producing Bacillus tropicus R3 and a strain of lactic acid-producing Lactococcus lactis Z5 as the research objects, the differences in growth and metabolism of the two strains under pure culture and co-culture conditions were compared, and the effects of strain Z5 on the growth and metabolism of strain R3 were explored using glucose and lactic acid as carbon sources. The results showed that under the pure culture conditions, the strain R3 had the highest propionic acid yield (1.793 g/L) when the mass concentration of lactic acid was 10 g/L, while strain Z5 had the highest lactic acid yield (9.75 g/L) when the mass concentration of glucose was 30 g/L. Under co-culture conditions, the lactic acid was only generated by glucose metabolism with strain Z5, while propionic acid was only generated by glucose metabolism with strain R3. The results of the effects of strain Z5 on the growth and metabolism of strain R3 indicated that when strain Z5 and R3 were inoculated simultaneously, the growth advantage of strain Z5 exceeded that of strain R3, lactic acid generated by glucose metabolism with strain Z5 could provide substrate for strain R3 to metabolize and generate propionic acid and succinic acid.

In this study, the color, physicochemical properties, flavor, and taste of 21 representative sweet Huangjiu samples from 6 major Huangjiu production regions in China were systematically analyzed using national standard detection methods combined with modern analytical techniques. The results showed that the overall quality of sweet Huangjiu from Fangxian, Hubei province showed the greatest differences compared to other regions. Specifically, in terms of color, sweet Huangjiu from Fangxian, Hubei province exhibited the highest brightness, sweet Huangjiu from Longyan, Fujian province displayed the most vibrant red hue, while sweet Huangjiu from Shaoxing, Zhejiang province presented the deepest yellow color. Regarding flavor and taste, sweet Huangjiu from Fangxian, Hubei province had the highest response values to W3C (aromatic compounds), W1S (short-chain alkanes) and W5S (nitrogen oxides) (P<0.05), whereas sweet Huangjiu from Qingdao, Shandong province had significantly higher bitterness, astringency and bitter aftertaste than sweet Huangjiu from Fangxian, Hubei province and Shaoxing, Zhejiang province (P<0.05). In terms of physicochemical qualities, the contents of total sugar and soluble solids in sweet Huangjiu from Zhenjiang, Jiangsu province and Heyuan, Guangdong province were higher (P<0.05). Sweet Huangjiu from Shaoxing, Zhejiang province was rich in amino acids, while sweet Huangjiu from Heyuan, Guangdong province possessed the highest alcohol content. The main distinguishing factors among sweet Huangjiu from different regions were identified as follows: aromatic compounds and L* value of sweet Huangjiu from Fangxian, Hubei province; alcohol content, total sugar, and soluble solids of sweet Huangjiu from Heyuan, Guangdong province and Zhenjiang, Jiangsu province; taste of sweet Huangjiu from Qingdao, Shandong province and Longyan, Fujian province, and a* value, amino acid nitrogen, W2W (aromatic compounds and organic sulfides), and W3S (long-chain alkanes) of sweet Huangjiu from Shaoxing, Zhejiang province.

Using soaked plum wine as the research object, the bitter was removed by amygdalin enzymatic hydrolysis method and β-cyclodextrin taste inhibition method. Taking removal rate of amygdalin as the evaluation index, two kinds of bitter removal processes were optimized by single factor tests and orthogonal tests. In addition, the correlation between amygdalin contents and bitter taste was discussed, and the color and odor of debitter soaked plum wine were determined by color difference instrument and electronic nose, respectively. The results showed that the optimal debittering process of amygdalin enzymatic hydrolysis method was as follows: amygdalinase addition 0.3 U/ml, enzymatic hydrolysis temperature 50 ℃, initial pH 4.8. The optimal debittering process of β-cyclodextrin taste inhibition method was as follows: β-cyclodextrin addition 1.0%, action temperature 40 ℃ and time 60 min. Under the optimal conditions, the removal rates of amygdalin in soaked plum wine were 25.54% and 23.92%, and the residues were 1.52 mg/L and 1.56 mg/L, respectively, which were lower than the threshold value (1.59 mg/L) in plum wine. The total color difference (ΔE value) of debitter wine sample with amygdalin enzymatic hydrolysis method and untreated wine sample was only 0.07, with less color difference. The typical fruit flavor substance benzaldehyde (methyl group) was well retained, the sulfur content was reduced, the sulfur odor was weakened, and the sensory quality of green plum wine was obviously improved. In conclusion, the two bitter removal processes could effectively reduce the bitter of soaked plum wine, and the amygdalin enzymatic hydrolysis method was better than β-cyclodextrin taste inhibition method.

In this study, using Panax quinquefolius, Lycium barbarum and glutinous rice as raw materials, and sweet Jiuqu as saccharification fermentation agent, P. quinquefolius and L. barbarum sweet fermented glutinous rice was prepared. Taking the alcohol content and sensory score as evaluation indexes, the fermentation process were optimized by single factor and response surface tests, and the physicochemical and microbiological indexes, the contents of total phenols and total flavonoids, and the antioxidant activity were analyzed. The results showed that the optimal fermentation process conditions of the wine were as follows: P. quinquefolius extract addition 5.0%, L. barbarum pulp addition 7.6%, sweet Jiuqu addition 1.0%, fermentation time 48 h, and temperature 30 ℃. Under the optimal process conditions, the sensory score of P. quinquefolius and L. barbarum sweet fermented glutinous rice was 94.4 points, the alcohol content was 1.83%vol, the contents of total acid and soluble solid were 4.63 g/L and 22.67%, respectively. It had a special fermentation aroma of sweet fermented glutinous rice, with orange yellow, sweet and sour. The contents of total flavonoids and total phenols of the wine were 127.7 mg/L and 28.1 mg/L, respectively. The half-inhibitory concentration (IC₅₀) values to 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals were 0.27 ml/ml and 0.716 ml/ml, respectively, indicating that the product had good antioxidant properties.

A method for the simultaneous determination of 13 non-phthalate plasticizers in strong-flavor (Nongxiangxing) Baijiu by gas chromatography- mass spectrometry (GC-MS) was established. The alcohol content of sample was diluted with water to about 20%vol, then extracted with n-hexane, and then extracted twice by vortex, ultrasound and centrifugation. The extracted solution was combined and concentrated by nitrogen blowing and then re-dissolved. The chromatographic column was Agilent HP-5MS column (30 m×0.25 mm×0.25 μm), the inlet temperature was 280 ℃, and the initial temperature of column oven was 70 ℃. A variety of non-phthalate plasticizers were detected by select ion monitoring (SIM) mode and quantified by external standard method. The results showed that the 13 non-phthalate plasticizers had a good linear relationship in the range of 0.02-1.0 mg/L, the correlation coefficient (R²)≥0.996 2, the limit of detection (LOD) were 0.002-0.05 mg/kg, and the limit of quantification (LOQ) were 0.006-0.15 mg/kg; The average standard recovery rates were 55.9%-113.8%, and the relative standard deviation (RSD) of precision tests results were 1.0%-8.8%. The method was accurate, efficient, rapid and simple, and could be used for the qualitative and quantitative detection of a variety of non-phthalate plasticizers in Baijiu.

In this study, using five cherry cultivars planted in the same area as materials, 27 kinds of mineral elements in cherries were detected by inductively coupled plasma-mass spectrometry (ICP-MS) technology, and the mineral element differences of different cherry cultivars were distinguished by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA) and correlation analysis. The results showed that five cherry cultivars were similar in element species, but significant differences in element content. The main elements with high content were K, Mg, Ca, Na and Fe. Both PCA and PLS-DA models could distinguish cherry cultivars, and the main characteristic elements were K, Mg, Ca and Fe. There was a correlation between many elements in cherries, like Se, As, K, Sn; Cd, Pb, Cr, Ni; Ba, Al, Ca, Mn, Sr, Fe, Mo, B, Mg, Ti, Co, Zn; and those three groups of elements were positively correlated within the group. It provided a reference for product development of supplementary mineral elements according to the needs of the relevant population.

A method for simultaneous determination of 11 organic acids (citric acid, isocitric acid, tartaric acid, succinic acid, malic acid, malonic acid, lactic acid, adipic acid, maleic acid, fumaric acid and ascorbic acid) in high-temperature Daqu was established using ultra-high performance liquid chromatography triple quadrupole tandem mass spectrometry (UPLC-MS/MS). The high-temperature Daqu sample was extracted and diluted with water, separated by Accucore aQ chromatography column (150 mm×2.1 mm, 2.6 μm), eluted with a gradient of methanol-0.2% formic acid water as the mobile phase at a flow rate of 400 μl/min and column temperature of 40 ℃, determined by negative ion multiple reaction monitoring mode (MRM), and quantified by the matrix external standard method. The results showed that the 11 organic acids had good linear relationships within their respective mass concentration ranges, with correlation coefficients R²≥0.996, the detection limit (LOD) were 0.08-4.13 μg/kg, the quantification limit (LOQ) were 0.27-13.76 μg/kg, the average recovery rates were 77.0%-113.0%, and the relative standard deviation (RSD) of precision tests results were 0.1%-11.5%. This method had simple pretreatment, short analysis time, high accuracy, and good repeatability, which was suitable for analyzing the contents of 11 organic acids in high-temperature Daqu samples.

Kombucha milk wine was prepared with fresh milk as the raw material and fermented by Kombucha and yeast. Using Kombucha milk wine as the blank group (CK), and the Kombucha five grains milk wine prepared by mixed fermentation with five grains as the experimental group (WG), the volatile flavor substances were determined by gas chromatography-ion mobility spectrometry (GC-IMS) technology, and principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were performed based on the results. The results showed that a total of 40 volatile flavor substances were detected in the two milk wine samples, including 10 alcohols, 16 esters, 5 ketones, 5 aldehydes, 2 hydrocarbons, 1 heterocyclic compound, and 1 terpene compound. The proportion of ester substances in the Kombucha milk wine (43.00%) was higher than that in the control (CK) (31.89%). PCA and OPLS-DA could effectively distinguish the two types of milk wine samples. Based on the relative odor activity value (ROAV) and variable importance in projection (VIP) value, 6 key volatile flavor substances (ROAV>1) and 14 differential volatile markers (VIP>1). To sum up, the malt flavor, herbal flavor, green flavor and apple flavor of the milk wine were increased by adding five grains fermentation.

Taking Baijiu enterprises as the research objects, a relational model was constructed with brand anthropomorphism as the independent variable, psychological distance as the mediating variable, and purchase intention as the dependent variable based on stimulus-organism-response (SOR) theory. Through questionnaire surveys and empirical research, the results indicated that both impression-based cues and interaction-based cues of brand anthropomorphism could positively influence consumer purchase intentions, with the influence of impression-based cues being more significant. Psychological distance served as a mediating factor in the relationship of influence brand anthropomorphism on consumer purchase intentions. Based on these findings, countermeasures and suggestions were proposed for Baijiu enterprises, including designing unique Baijiu brand anthropomorphism images, fully leveraging the interactive attributes of Baijiu brands, and implementing reasonable anthropomorphism strategies to achieve differentiated marketing.

Aiming at the financial performance evaluation of Baijiu enterprises, selecting Luzhou Laojiao Co., Ltd. as the main research object and 16 listed Baijiu companies as samples, the financial performance evaluation index system of Baijiu enterprises was constructed from the four dimensions of profitability, operating capacity, debt paying capacity and development capacity. The financial performance ranking and competition situation HASSE diagram of Baijiu enterprises were obtained based on partial order set decision method. On this basis, partial order dynamic sensitivity analysis was carried out to identify the key influencing factors of financial performance. The research showed that this evaluation method avoided the weight assignment problem in the process of multi-index evaluation, revealed the countermeasures to improve financial performance, had important theoretical value and practical significance for improving the financial performance level of Luzhou Laojiao and promoting the high-quality development of Baijiu industry, and provided reference and inspiration for the improvement of financial performance evaluation methods.

Under the background of globalization and rapid development of information technology, digital marketing transformation of Guizhou's medium-, small- and micro-sized sauce-flavor (Jiangxiangxing) Baijiu enterprises has become the key to gaining competitive advantages in the market. Based on literature review and theoretical exploration methods, the challenges faced by Guizhou's medium-, small- and micro-sized sauce-flavor Baijiu enterprises in terms of technology adoption, cultural content creation, user engagement and market positioning were analyzed. The study found that these challenges can be effectively addressed by implementing strategies such as technological innovation, cultural integration, user interaction enhancement and market positioning optimization. The results provided practical guidance for the digital marketing transformation of Guizhou's medium-, small- and micro sauce-flavor Baijiu enterprises, while contributing new perspectives to the theoretical study of digital marketing, which had certain theoretical and practical significance.

The wine tourism industry, as an innovative sector combining wine production and tourism experiences, has developed rapidly in recent years, becoming a key force in promoting regional economic growth, cultural exchange, and ecological conservation globally. The development of the global wine tourism industry was reviewed, major business models and practices across different countries were analyzed, and the multifaceted values of wine tourism in cultural preservation, economic growth, and brand building was explored. Based on tourism experience and experience economy theories, a comprehensive wine tourism system model was proposed. Recommendations such as resource integration, brand building, innovative experiences, quality improvement, differentiated marketing, and policy support were provided, aiming to offer valuable insights for enhancing China's international competitiveness in wine tourism and ensuring its sustainable development.