Effects of Various Flavors of Baijiu on the Microbial Communities, Metabolic Pathways, and Flavor Structures of Dongbei Suancai.

This study aimed to assess the effects of Chinese Baijiu with different flavors as supplementary material on microbial communities and flavor formation during inoculated fermentation of Chinese Dongbei Suancai. The results showed that the addition of Fen flavor Baijiu significantly increased the relative abundance of Candida, Luzhou flavor Baijiu increased the relative abundance of Pedobacter and Hannaella, while Maotai flavor Baijiu increased the Chryseobacterium and Kazachstania. A total of 226 volatile metabolites were detected in Suancai fermented when adding different flavors of Baijiu. Furthermore, the significantly upregulated metabolites (p < 0.01) of Suancai after adding Baijiu increased by 328.57%, whereas the significantly downregulated metabolites decreased by 74.60%. Simultaneously, the addition of Baijiu promoted the synthesis and decomposition of amino acids and short-chain fatty acids in the early and middle stages of fermentation. Further, Maotai flavor Baijiu improved the diversification of metabolic pathways in the late stage of Suancai fermentation. The E-nose response showed that sulfur-organic, broad-alcohol, sulfur-chlor was the principal differential flavor in Suancai caused by adding Baijiu with different flavors. Simultaneously, Fen flavor Baijiu and Luzhou flavor Baijiu accelerated the formation of the Suancai flavor. These results indicated that Baijiu with different flavors had significant effects on the flavor formation of inoculated fermented Suancai.

Effects of inoculation with a binary mixture of Lactobacillus plantarum and Leuconostoc citreum on cell wall components of Chinese Dongbei suancai.

This study aimed to investigate the effects of inoculation with a starter culture consisting of Lactobacillus plantarum LNJ002 and Leuconostoc citreum BNCC 194779 on microbial community, cell wall polysaccharide characteristics, cell wall degrading enzymes, and microstructure during Chinese Dongbei suancai fermentation. The results showed that Lactobacillus (98.75%) was the dominant genus during fermentation of Dongbei suancai. The principal coordinates analysis (PCoA) suggested that inoculation with Lactobacillus promoted the stability of microbial community structure during Chinese Dongbei suancai fermentation. Besides, the lower content in cellulose (80.28 ± 2.61 ug/mg) and pectin (53.56 ± 2.67 ug/mg) observed in the inoculated fermented suancai. Simultaneously, the inoculated fermented suancai had the most decreases in SR 1 (70.35%) and SR 3 (72.06%) and the most increase in SR 2 (950%), which suggested that inoculation intensified the decrease of the linearity and the RG-1 branching degree of pectin. The contents of polygalacturonase (PG) and pectin methylesterase (PME) in inoculated fermented suancai were 21.06% and 21.86% higher than those in naturally fermented suancai. In addition, the surface of suancai leaves gradually changed from smooth to rough during fermentation, which was accelerated by inoculation. Moreover, Lactobacillus, Aspergillus, Wallemia and Mucor were all negatively correlated with cellulose and GalA. These results revealed that inoculation promoted the formation of dominant genus structure during suancai fermentation, changed the effects of enzymes on the degradation of cell wall components, thereby accelerated the formation of Chinese Dongbei suancai texture.

Microbial communities and metabolite profiles during the fermentation of Chinese Dongbei suancai with Chinese baijiu as supplementary material.

BACKGROUND: In industrial production of suancai, baijiu is commonly used to inhibit the spoilage bacteria and enhance the flavor. However, the effects of baijiu on the microbial diversity and metabolic pathways of suancai are rarely reported in the literature. This study aimed to explore the microbial community, its predicted functional roles, and the metabolites formed during fermentation of Chinese Dongbei suancai fermented using a mixed starter with Chinese baijiu as supplementary material. RESULTS: Results showed that Lactobacillus, Enterobacter, and Leuconostoc were the major bacterial genera in the Dongbei suancai fermented by adding baijiu. Linear discriminant analysis effect size indicated that Leuconostoc was the major biomarker in the early stage of fermentation, whereas Lactococcus, Weissella, and Lactobacillus plantarum were biomarkers in the middle and later stages of fermentation. A total of 638 metabolites were detected in suancai fermented by adding baijiu. However, the principal component analysis showed that baijiu significantly affected the metabolites of suancai in the early and later stages of fermentation. Furthermore, 58, 22, and 26 significantly differential metabolites (P < 0.01) were found on day 0, day 2, and day 30 of fermentation respectively. Moreover, Lactobacillus, Lactococcus, and Enterobacter had positive correlations with amino acids, nucleotides, organic acids, alcohols, and esters. Functional analysis implied that carbohydrate, amino acid, energy, and nucleotide metabolism were the major determinants of the characteristics of suancai fermented with baijiu as supplementary material. CONCLUSION: Baijiu changed the metabolites of inoculated fermented Dongbei suancai. © 2023 Society of Chemical Industry.

Path analysis of non-enzymatic browning in Dongbei Suancai during storage caused by different fermentation conditions.

A non-enzymatic browning reaction occurs easily in Dongbei Suancai (DS) during storage. Using the method of path analysis, the changes in contents of VC (ascorbic acid), polyphenol, reducing sugar, amino nitrogen, and 5-HMF (5-hydroxymethyl furfural) were investigated to analyze the direct pathways and determinants of browning caused by pre-production blanching at 100 °C (R-100), salt-addition increased from 2% to 6% (Y-6) and fermentation time extended from 30 d to 40 d (T-40), respectively. The results showed that R-100 could delay the browning by inhibiting two direct pathways of oxidative decomposition of VC and oxidation-polymerization of polyphenols, but T-40 could lead to an increase in degree of browning for which primary determinant was the interaction between polyphenol and reducing sugar, while Y-6 had no obvious effect on browning pathway and determinants. R-100 was thus deemed to be a good measure with inhibiting non-enzymatic browning in DS during storage.

Key composition optimization of meat processed protein source by vacuum freeze-drying technology.

Vacuum freeze-drying technology is a high technology content, a wide range of knowledge of technology in the field of drying technology is involved, it is also a method of the most complex drying equipment, the largest energy consumption, the highest cost of drying method, but due to the particularity of its dry goods: the freeze-drying food has the advantages of complex water performance is good, cooler and luster of freezing and drying food to maintain good products, less nutrient loss, light weight, easy to carry transportation, easy to long-term preservation, and on the quality is far superior to the obvious advantages of other dried food, making it become the forefront of drying technology research and development. The freeze-drying process of Chinese style ham and western Germany fruit tree tenderloin is studied in this paper, their eutectic point, melting point and collapse temperature, freeze-drying curve and its heat and mass transfer characteristics are got, then the precool temperature and the highest limiting temperature of sublimation interface are determined. The effect of system pressure on freeze-dried rate in freeze-drying process is discussed, and the method of regulating pressure circularly is determined.

Effects of soybean oligosaccharides on intestinal microbial communities and immune modulation in mice.

Soybean oligosaccharides (SBOSs) are potential prebiotics that may be used to improve immune function. Here, we investigated the effects of intragastric administration of SBOSs in mice to determine the effects on autochthonous intestinal microbial communities and immunological parameters. Results E: After 22-day administration, 4.0 g kg body weight (BW)-1 SBOSs significantly enhanced the proliferation of bifidobacteria and lactic acid bacteria (LAB) as compared to the control. This dose of SBOSs also significantly increased numbers of enterococci and decreased numbers of Clostridium perfringens. Treatment with 4.0 g kg BW-1 SBOSs also significantly increased the percentage of T-lymphocytes and lymphocyte proliferation as compared to the control, suggesting that SBOSs promoted cellular immunity in mice. Additionally, 4.0 g kg BW-1 SBOSs induced significant differences in hemolysin production, natural killer (NK) cell activity, phagocytic activity, cytokine production, and immunoglobulin levels compared to the control. CONCLUSION: Our data demonstrated that intragastric administration of SBOSs at a dose of 4.0 g kg BW-1 improved the numbers of beneficial intestinal microbes and enhanced immunological function of mice. Therefore, these data supported that SBOSs may have applications as a prebiotic to improve immune responses in humans. Further studies are warranted.