Search Results (182)

Burdock (Arctium lappa L.) is a medicinal and edible homologous plant whose roots contain many bioactive substances such as polysaccharides and phenolics. This study explored the integration of burdock powder and lactic acid bacteria fermentation to enhance the nutritional quality, sensory attributes, and flavor profiles of duck sausages. Three bacterial strains, Lacticaseibacillus casei, L. helveticus, and L. plantarum, were selected based on sensory analysis, and their effects on sausage properties were evaluated through combined fermentation trials. The results demonstrated that duck sausages fermented with L. plantarum and L. helveticus and supplemented with 3% burdock powder (PHB group) exhibited > 1.5-fold higher antioxidant activity (ABTS at 85.2 μmol trolox/g and DPPH at 92.7 μmol trolox/g, respectively; p < 0.05) and 15% increase in total phenolic content (8.24 mg gallic acid/g) compared to non-fermented counterparts. The PHB formulation also enhanced color stability (lightness, redness, yellowness), textural characteristics (hardness, springiness, cohesiveness), and sensory acceptability. Volatile compound analysis revealed a reduction in off-odor aldehydes (hexanal, (E)-2-octenal, (E)-2-decenal, and (E,E)-2,4-decadienal) and increased production of desirable aromatic compounds like tetramethyl-pyrazine. These findings highlight the potential of combining lactic acid bacteria fermentation with burdock powder to develop functional duck sausages with improved nutritional and sensory properties. Full article

To advance the development of protein-rich plant-based foods, a novel binder system for vegan sausage alternatives without the requirement of heat application was investigated. This enables long-term ripening of plant-based analogs similar to traditional fermented meat or dairy products, allowing for refined flavor and texture development. This was achieved by using a poorly water-soluble calcium source (calcium carbonate) to introduce calcium ions into a low-ester pectin—gluten matrix susceptible to crosslinking via divalent ions. The gelling reaction of pectin–gluten dispersions with Ca²⁺ ions was time-delayed due to the gradual production of lactic acid during fermentation. Firm, sliceable matrices were formed, in which particulate substances such as texturized proteins and solid vegetable fat could be integrated, hence forming an unheated raw-fermented plant-based salami-type sausage model matrix which remained safe for consumption over 21 days of ripening. Gluten as well as pectin had a significant influence on the functional properties of the matrices, especially water holding capacity (increasing with higher pectin or gluten content), hardness (increasing with higher pectin or gluten content), tensile strength (increasing with higher pectin or gluten content) and cohesiveness (decreasing with higher pectin or gluten content). A combination of three simultaneously occurring effects was observed, modulating the properties of the matrices, namely, (a) an increase in gel strength due to increased pectin concentration forming more brittle gels, (b) an increase in gel strength with increasing gluten content forming more elastic gels and (c) interactions of low-ester pectin with the gluten network, with pectin addition causing increased aggregation of gluten, leading to strengthened networks. Full article

Biogenic amines (BAs) are frequently detected in seafood products, wines, and fermented foods, and they pose potential risks to human health. The current study analyzed the concentrations of five common BAs in seafood, fermented food, and complementary food for infants and children (fish sausage, canned complementary food for infants containing fish and shrimp ingredients, and fish floss) in China and estimated the acute health risks of histamine (HIS) from fermented foods in Chinese consumers. Among all the samples analyzed, HIS exhibited the highest detection rate (51.9%), followed by PUT (50.1%), and the detection rate of TRY (12.5%) was the lowest. The total average concentration of the five BAs across major food categories revealed that fermented bean curd had the highest total concentration of BAs (816.8 mg/kg), followed by shrimp (383.2 mg/kg) and cheese (328.0 mg/kg). In contrast, samples of complementary food for infants and children contained the lowest concentrations of BAs; the total average concentration of the five BAs was 12.0 mg/kg. The point assessment results showed that acute dietary exposure to HIS was highest from cheese (76.2 mg/d), followed by fermented bean products (74.5 mg/d). Furthermore, the probability assessment indicated that the probability of acute health risks from exposure to HIS was 0.44% for fermented bean product consumers and 0.014% for cheese consumers, respectively. Thus, for the general consumer, the probability of acute health risks caused by HIS in seafood and fermented foods is low. However, individuals with high consumption of cheese and fermented bean products may need to be concerned. Full article

The objective of this study was to perform a preliminary in vitro characterization of Lactiplantibacillus plantarum BG112, assessing its safety and technological features for potential application as a culture starter for an industrial fermented dry meat product. In vitro assays assessed its viability, probiotic properties, and safety for use in food formulations. The strain was characterized through morphological and biochemical tests, carbohydrate fermentation profiling, and various in vitro assays based on FAO/WHO criteria for probiotic selection. These included proteolytic activity, auto-aggregation capacity, tolerance to simulated gastric juice and bile salts, antimicrobial activity, and resistance to sodium chloride, nitrite, and low pH. Safety evaluations were also performed by testing antibiotic susceptibility, hemolytic activity, and DNAse production. The results showed that L. plantarum BG112 exhibited strong tolerance to adverse environmental conditions typically found during sausage fermentation and ripening, along with significant inhibitory activity against pathogenic bacteria, such as Escherichia coli O157:H7, Salmonella Typhimurium, and Staphylococcus aureus. The strain also demonstrated no hemolytic or DNAse activity and presented a favorable antibiotic sensitivity profile, meeting key safety requirements for probiotic use. Further studies using meat matrices and in vivo models are needed to validate these findings. This study contributes to the early-stage selection of safe and technologically suitable strains for use in fermented meat products. These findings support the potential application of L. plantarum BG112 as a safe and effective starter culture in the development of high-value, premium fermented meat products, aligned with current consumer demand for health-enhancing and natural foods. Full article

The production of fermented sausages from poultry meat using traditional technologies and natural maturation conditions is a major challenge. The aim of this study was to identify indigenous microbiota with antilisterial activity from an innovative, additive-free, traditionally fermented chicken sausage. Isolates (n = 88) of lactic acid bacteria (LAB) were collected during maturation and subjected to MALDI-TOF mass spectrometry identification. The capacity to combat Listeria was screened against five strains using the agar well diffusion method in 63 selected LAB isolates. MALDI-TOF mass spectrometry identified four different LAB genera, namely Enterococcus, Lactococcus, Leuconostoc and Lactobacillus, the proportions of which differed significantly during the production phases (p < 0.001). Enterococcus faecalis was the most prevalent LAB species in the initial sausage dough. The presence of lactococci (Lactococcus lactis) and enterococci was detected during the 14- and 30-day ripening period and was gradually displaced by leuconostocs and lactobacilli. Lactobacilli appeared to be abundant during the central and late maturation phases, and consisted of only two species—Latilactobacillus sakei and Latilactobacillus curvatus. In total, 38 LAB isolates (60%) showed antilisterial activity toward at least one Listeria indicator strain. The proportions of antilisterial LAB differed significantly during sausage maturation. Inhibitory activity against all indicator Listeria was detected in the neutralized cell-free supernatants of five strains of Enterococcus faecalis, two L. sakei strains and one Leuconostoc mesenteroides strain. The antilisterial activity observed in the indigenous LAB revealed the possible role of L. sakei as a bioprotective culture, as well as the role of Ln. mesenteroides and E. faecalis as bacteriocin producers, for practical applications. Full article

Deep learning has great potential in the field of functional peptide prediction. This study combines metagenomics and deep learning to efficiently discover potential umami peptides in fermented sausages. A candidate peptide library was generated using metagenomic data from fermented sausages, an integrated deep learning model was constructed for prediction, and SHAP (SHapley Additive exPlanations) interpretability analysis was performed to elucidate the key amino acid features and contributions of the model in predicting umami peptides, screening the top ten peptides with the highest predicted probability. Subsequently, molecular docking was performed to assess the binding stability of these peptides with the umami receptor T1R1/T1R3, selecting the three peptides DDSMAATGL, DGEEDASM, and DEEEVDI with the most stable binding for further study. Docking analysis revealed the important roles of the key receptor residues Glu301, Arg277, Lys328, and His71 in hydrogen bond formation. Molecular dynamics simulations validated the robust integrity of the peptide–receptor associations. Finally, sensory evaluation demonstrated that these three peptides possessed significant umami characteristics, with low umami thresholds (0.11, 0.37, and 0.44 mg/mL, respectively). This study, based on metagenomics and deep learning, provides a high-throughput strategy for the discovery and validation of functional peptides. Full article

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. Full article

In this study, 43 strains of Staphylococcus spp. and 22 strains of lactic acid bacteria (LAB), isolated from six representative fermented meat products (domestic and international), were subjected to a comprehensive safety evaluation, including hemolytic activity, catalase test, hydrogen sulfide production, and antibiotic susceptibility screening. Nine strains were selected for secondary screening based on safety criteria, fermentation characteristics, and acid and salt tolerance tests. Two optimal strains were identified—Staphylococcus saprophyticus LH-5 and Latilactobacillus sakei OFN-11—demonstrating excellent compatibility and no mutual antagonism. Both strains were non hemolytic, catalase positive, susceptible to some of the antibiotic tested, and did not produce hydrogen sulfide, mucus, or gas. These favorable fermentation characteristics included lipase/protease production, amino acid decarboxylase negativity, and salt and acid tolerance. Application experiments in fermented sausages were analyzed for 55 volatile compounds, related to meaty, fruity, and fatty aroma profiles compared to commercial starter cultures. The formulation including the selected strains exhibited lower acidity than its commercial unterparts while maintaining superior sensory and physicochemical attributes. These findings suggest that the S. saprophyticus LH-5 and L. sakei OFN-11 consortium holds promising potential as a starter culture for fermented meat products, offering technological advantages to become a fermentation agent that meets the preferences of Chinese consumers. Full article

Mangifera indica L. by-products obtained by three extraction methods from three cultivars (Keitt, Sensation and Gomera-3) were tested for their antibacterial properties against 20 bacterial species. These species were selected based on their relevance to winemaking processes (Acetobacter, Gluconobacter and Gluconacetobacter), fermented meat products (Staphylococcus) and human diseases (Pseudomonas, Escherichia, Shigella and Klebsiella). All mango by-product extracts showed antimicrobial activity in agar diffusion and broth microdilution experiments. However, differences in antimicrobial activity against acetic acid bacteria were detected between the peel extracts obtained from the two extraction processes. Furthermore, a wide range of minimum inhibitory concentration (MIC) data were found; Staphylococcus spp. (10 species) showed MICs between 1.0–240 mgGAE/mL and Acetobacter spp. (4 species) showed MICs between 1.7 and 200 mgGAE/mL. The most sensitive bacteria belonged to the staphylococcal species (MIC: 1 mgGAE/mL) and the most resistant was Gluconacetobacter saccharivorans (MIC > 400 mgGAE/mL). In general, there was no significant correlation between the phenolic compounds identified and the MIC values. The minimum bactericidal concentration (MBC) revealed that the mango extracts had a bacteriostatic effect. A simple and reliable method for the determination of MIC and MBC in microdilution assays with acetic acid bacteria was described. These results highlight the antibacterial properties of mango by-products against species associated with food spoilage microorganisms and human diseases. Full article

The metabolic activity of fermentative microorganisms plays a critical role in determining the flavor profile of fermented meat products. Modulating carbon and nitrogen sources represents a promising strategy for enhancing product quality. In this study, Debaryomyces hansenii strains isolated from dry-cured ham were assessed in a sterile sausage model to evaluate the effects of different carbon sources (sucrose, corn starch) and nitrogen sources (leucine, soy protein isolate) on colony growth, enzyme activity, and physicochemical properties. These nutritional factors significantly affected the fermentation performance of D. hansenii. Corn starch and soy protein isolate increased colony count by 14.94% and 90%, respectively, and enhanced protease activity by 2-fold and 4.5-fold. Both treatments maintained high lipase activity (>50 U/g). Both supplements improved the water-holding capacity and decreased the water activity. Carbon sources reduced the medium pH, whereas nitrogen sources contributed to the maintenance of pH stability. A further analysis indicated that corn starch promoted the accumulation of aldehydes and ketones, which intensified the sourness and suppressed the saltiness. In contrast, soy protein isolate increased the abundance of free amino acids associated with umami and sweetness, and stimulated the formation of esters, ketones, and pyrazines, thereby enhancing flavor richness and umami intensity. Both ingredients also reduced saturated fatty acid levels and increased the unsaturated to saturated fatty acid ratio. Soy protein isolate exhibited a more pronounced effect on D. hansenii fermentation. This study provides a technical reference for enhancing the flavor characteristics of fermented meat products via the adjustment of carbon and nitrogen sources to regulate D. hansenii fermentation. Full article

Yersinia pseudotuberculosis is a foodborne pathogen with an animal reservoir, thus being able to spread via contaminated meat. The survival of Y. pseudotuberculosis during the ripening and storage of artificially contaminated spreadable fermented sausage (Teewurst) and dry fermented sausage was studied, with initial counts of 8 log, 6 log, and 3 log CFU/g. While the pathogen was completely inhibited in all batches of dry fermented sausage after 4 d of ripening and was thus absent in the final product, it survived much better in the spreadable sausage, characterized by a higher pH and fat content. The counts in the Teewurst final product (after 2 d of ripening) dropped from 8 log, 6 log, and 3 log CFU/g to approx. 6.3, 2.4, and 1.4 log CFU/g, respectively. For the initial concentrations 6 log and 3 log CFU/g, at least 1 out of six samples was still positive after 20 d of cold storage. On the other hand, in the batches with the highest initial counts (8 log CFU/g), all the samples were positive at the end of the experiment (37 d). The rapid decline in pH caused by the starter culture was an effective barrier for Y. pseudotuberculosis in dry fermented sausages, but the pathogen was able to persist in Teewurst. Full article

This study investigated the beneficial effects of individual and co-inoculation with Lactobacillus delbrueckii subsp. lactis N102 and Lactobacillus sakei H1-5 on improving safety parameters, sensory characteristics, and non-volatile metabolite profiles in dry-fermented sausages. Comprehensive analyses were conducted throughout the 20-day maturation period (0, 6, 13, 16, and 20 days), including physicochemical monitoring (moisture content, malondialdehyde (MDA) levels, biogenic amine concentrations, and sodium nitrite residues); sensory evaluation (color parameters and textural properties); and ¹H NMR-based metabolomic profiling. Key findings revealed strain-specific advantages: the N102 inoculation significantly delayed lipid oxidation, achieving the lowest final MDA concentration (4.5 mg/kg) among all groups. Meanwhile, H1-5 supplementation notably improved color attributes (a*/b* ratio = 1.34). The co-inoculation strategy demonstrated synergistic effects through (1) accelerated acidification (pH 5.3 by day 6); (2) enhanced textural properties (significantly increased hardness and elasticity vs. control); (3) optimized water distribution (free water reduced to 0.56% with 64.73% immobilized water); and (4) a significant reduction in sodium nitrite residues (70% decrease) and complete elimination of phenylethylamine (total biogenic amines: 702.94 mg/kg). ¹H NMR metabolomics identified 30 non-volatile metabolites, and the co-inoculation significantly increased the amount of essential amino acids (leucine, isoleucine), flavor-related compounds (glutamic acid, succinic acid), and bioactive substances (gooseberry, creatine). These metabolites enhanced antioxidant capacity, freshness, and nutritional value. Our findings demonstrate that strategic co-cultivation of food-grade lactobacilli can synergistically enhance both the techno-functional properties and biochemical composition of fermented meat products, providing a viable approach for quality optimization in industrial applications. Full article

Autochthonous microorganisms play critical roles in shaping the quality of Chinese sausages and may be influenced by local climate and/or processing conditions. The present study aimed to reveal the interprovincial differences in microbial community between Sichuan and Guizhou sausages, as well as driving factors based on high-throughput sequencing and bioinformatic analysis. The results indicated that Cobetia, Debaryomycetaceae, Kurtzmaniella, and Candida zeylanoides served as biomarkers for Sichuan sausages. In contrast, Enterococcus, unclassified Cyanobacteriales, Lactobacillales, Aspergillus vitricola, Mortierella, Fusarium, and Penicillium were identified as biomarkers for Guizhou sausages. Furthermore, salt content and moisture level showed positive correlations with Cobetia, Staphylococcus, Debaryomyces, and Kurtzmaniella, mainly found in Sichuan sausages. Conversely, pH and water activity (Aw) were positively associated with potential pathogenic bacteria (e.g., Vibrio, Cyanobacteria, Enterococcus, and Aeromonas) and fungi (e.g., Aspergillus, Fusarium, and Penicillium), which were mainly distributed in Guizhou sausages. Notably, microbial composition discrepancies between Sichuan and Guizhou sausages were primarily driven by processing conditions rather than regional climate factors. Collectively, these findings provide valuable insight for developing novel specific starters. Full article

The behavior of Listeria monocytogenes (L. monocytogenes) throughout the shelf life of ready-to-eat foodstuffs represents a major concern in relation to human diet and human health. The aim of the study was to evaluate the behavior of L. monocytogenes in Wiener sausage, as an RTE meat product, throughout 15 days of storage (0–7 °C) under the action of fermented juice from parsley (Petroselinum crispum var. tuberosum) roots and common hawthorn (Crataegus monogyna) berry phenolics, compared with the effect of the food additives sodium nitrite and sodium ascorbate used in the standard formulation. For this purpose, one experimental formulation (F1) and one standard formulation (F2) of Wiener sausages were designed using the following preservatives and antioxidants: 50 ppm fermented parsley root juice (as a nitrite source) and 50 ppm hawthorn berry phenolics were used in F1, and 50 ppm sodium nitrite (as food additive E 250) and 50 ppm sodium ascorbate (as food additive E 301) were used in F2. The ability to support L. monocytogenes growth was assessed by a challenge test throughout the 15 days of storage. Based on the results of the assessment, the natural ingredients fermented parsley root juice and hawthorn berry phenolics could act as preservatives that ensure microbiological safety during the shelf life of the product. The nitrite and phenolic compounds of these natural ingredients showed antimicrobial activity against foodborne pathogens, including L. monocytogenes. Full article

The aim of the study was to use a commonly employed technology in the meat industry, the inoculation of a biocontrol starter, in the processing of a plant-based fermented dry-cured sausage analog to improve its safety against possible Listeria monocytogenes contamination. Challenge tests were used to select suitable lactic acid bacteria (LAB) for the analog under industrial production conditions. First, 20 LAB strains were tested in vitro and five of them were further tested by stuffing the ingredients under industrial conditions. The L. monocytogenes counts highlighted Latilactobacillus sakei 205 as the most protective one, achieving a reduction of 2.6 log CFU/g. Further, a triangular test and Check-All-That-Apply test were performed to understand the organoleptic differences that could be expected in the final product. The batch inoculated with Llb. sakei 205 did not show any sensory differences from the commercial batch. Therefore, Llb. sakei 205 was identified as a potential protective starter due to the microbiological and sensory results. This pioneering study applied biocontrol starters to plant-based meat analogs, aligning with clean-label trends. Full article