Latilactobacillus sakei (L. sakei) and Staphylococcus carnosus (S. carnosus) are common starters for fermented sausages. However, the mechanism underlying the effects of these two microorganisms on co-cultivation in sausages remains unclear. This study compared the changes in metabolomics following fermentation by L. sakei and S. carnosus individually and in combination. After two days of fermentation, the pH values of the LS (Latilactobacillus Single), SC (Staphylococcus Single), and LSSC (Latilactobacillus-Staphylococcus Combined) groups were 4.59, 5.19, and 4.86. By comparing the common differential metabolites among the three groups, it was found that the content of N2-acetyl-L-ornithine decreased after single fermentation with L. sakei, while the content of N2-acetyl-L-ornithine increased after single fermentation with S. carnosus and combined fermentation with L. sakei. Additionally, KEGG pathway analysis identified eight key metabolic pathways, including purine metabolism, starch and sucrose metabolism. In addition, it was found that L. sakei produced D-Galactose during fermentation, which could be utilized by S. carnosus. The co-fermentation of L. sakei and S. carnosus promoted the production of D-sorbitol. Our results suggest that the metabolic interactions between L. sakei and S. carnosus increase the number of functional metabolites in co-fermented sausages. These findings provide valuable insights and new research directions for the study of LAB and CNS interactions, as well as for the development of fermentation agents.

Beef and yam are valued as functional foods, yet their synergistic effects on gastrointestinal health and immunity remain underexplored. This study investigated the effects of beef and yam on the spleen and stomach. In the present study, a rat model of spleen deficiency was established by poor diet and exhaustive swimming. The weight, food intake, gastrointestinal and immune indexes, and the intestinal flora of the rats were examined. The results showed that the levels of gastrin, motilin, and four cytokines improved. Specifically, the beef group exhibited marked recovery in gastrointestinal hormones, with serum gastrin and motilin levels increasing to approximately 60 pg/mL and 70 pg/mL, respectively, close to the normal control levels, and significantly higher than the model group. The beef and yam effectively restored the balance of intestinal flora, which significantly increased the diversity of intestinal microorganisms. In addition, the tissue structure of the spleen, stomach, small intestine, and colon was also effectively improved. Additionally, yam increased gut microbial diversity and optimized the microbial community structure, consequently enhancing the overall health status. This study elucidates the multi-pathway mechanisms by which beef and yam ameliorate spleen deficiency, providing a scientific basis for their application in functional foods.

Myofibrillar protein (MP) emulsion systems tend to be unstable, leading to loss of water and oil from the emulsion gel. Thus, improvements in MP emulsification ability are needed to enhance the quality of meat products. The effects of different added concentrations of locust bean gum (LBG) (0–5 mg/g) on the emulsion gel performance of bovine MP were studied. LBG can act on myosin to stretch the spatial structure of the protein and thus improve the thermal stability of the emulsion. LBG can enhance the hydrophobicity of the MP emulsion gel molecules, allowing greater combination of the oil phase with protein, optimizing the protein’s secondary structure, and promoting greater order and uniformity in the network structure of the MP emulsion gel. LBG imparts better texture characteristics and water retention properties to MP emulsion gels. Compared with a control group, adding 5 mg/g LBG can increase the hardness of an MP emulsion from 23.11 g to 65.91 g, springiness from 0.74 to 0.82, and water holding capacity from 59.45% to 93.24%. This study provides a reference for improving the quality of beef protein-based food emulsion gel.