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Background: Mild Colombian coffees are recognized worldwide for their high-quality coffee cup. However, there have been some failures in post-harvest practices, such as coffee grain fermentation. These failures could occasionally lead to defects and inconsistencies in quality products and economic losses for coffee farmers. In Colombia, one of the fermentation methods most used by coffee growers is wet fermentation, conducted by submerging the de-pulped coffee beans for enough time in water tanks to remove the mucilage. Objectives: We evaluated the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours) on the total number of microbial groups. We also identified microorganisms of interest as starter cultures. Methods: We used a completely randomized experimental design with two factors; the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours), for 9 treatments with two replicates. During the coffee fermentation (1,950 g), the pH and °Brix were monitored. Total counts of different microbial groups (mesophiles, coliforms, lactic-acid bacteria, acetic-acid bacteria, and yeasts) were performed. Various isolates of microorganisms of interest as starter cultures (lactic-acid bacteria and yeasts) were identified using molecular sequencing techniques. Results: 21 lactic-acid bacteria (LAB) isolates and 22 yeasts were obtained from the different mini-batch fermentation systems. The most abundant lacticacid bacteria species found were Lactiplantibacillus plantarum (46%) and Levilactobacillus brevis (31%). Pichia kluivery (39%) and Torulaspora delbrueckii (22%) were the most abundant yeast species. Conclusion The studied factors did not have effect over the microorganism's development. The identified bacterial and yeasts species have potential as starter cultures for better-quality coffees and in fermentation-related applications. [ABSTRACT FROM AUTHOR]

Background: Mild Colombian coffees are recognized worldwide for their high-quality coffee cup. However, there have been some failures in post-harvest practices, such as coffee grain fermentation. These failures could occasionally lead to defects and inconsistencies in quality products and economic losses for coffee farmers. In Colombia, one of the fermentation methods most used by coffee growers is wet fermentation, conducted by submerging the de-pulped coffee beans for enough time in water tanks to remove the mucilage. Objectives: We evaluated the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours) on the total number of microbial groups. We also identified microorganisms of interest as starter cultures. Methods: We used a completely randomized experimental design with two factors; the effect of the water (g)/de-pulped coffee (g) ratio (I: 0/25, II: 10/25, III: 20/25) and final fermentation time (24, 48, and 72 hours), for 9 treatments with two replicates. During the coffee fermentation (1,950 g), the pH and °Brix were monitored. Total counts of different microbial groups (mesophiles, coliforms, lactic-acid bacteria, acetic-acid bacteria, and yeasts) were performed. Various isolates of microorganisms of interest as starter cultures (lactic-acid bacteria and yeasts) were identified using molecular sequencing techniques. Results: 21 lactic-acid bacteria (LAB) isolates and 22 yeasts were obtained from the different mini-batch fermentation systems. The most abundant lactic-acid bacteria species found were Lactiplantibacillus plantarum (46%) and Levilactobacillus brevis (31%). Pichia kluivery (39%) and Torulaspora delbrueckii (22%) were the most abundant yeast species. Conclusion The studied factors did not have effect over the microorganism’s development. The identified bacterial and yeasts species have potential as starter cultures for better-quality coffees and in fermentation-related applications.

The influence of the starter cultures, such as Lactobacillus rhamnosus, L. plantarum, Kocuria rosea, Staphylococcus carnosus, L. plantarum, L. rhamnosus and L. paracasei, on the functional-technological and physicochemical characteristics of the pork meat during the salting is investigated in this paper. It has been proven that the use of these starter cultures in the technology of raw ba-lik products makes it possible to obtain finished products with improved quality indicators, which is promising in the food industry. It had been shown that in the pork meat samples with the starter cultures, the acidity from 5.74 pH units is more intensively decreased – to 5.52 pH units compared to the control sample (up to 5.64 pH units). Using the starter cultures based on nitrite-reducing microorganisms for the salting in 72 hours positively influenced the formation of the required colour characteristics. It had been established that the moisture-binding capacity and plasticity of the pork meat samples with the starter cultures are characterised by the increased indicators compared with the control sample – by 4.73% and 7.73% and by 2.19 cm2.g, respectively. The difference in the volatile fatty acids content in the pork meat samples with the starter cultures compared with the control sample is 22 and 33%, respectively, in 72 hours of salting. The obtained results can be used in the enterprises of the meat processing industry to produce fermented meat products, particularly raw dried logs.

Microstructural changes in meat that occur during refrigerated storage depend on the hygiene of slaughtering and primary processing of animal carcasses, their cooling conditions, storage period, and microbial contamination and reflect the processes of meat maturation and spoilage. To extend the shelf life of pork in half-carcasses in a chilled state, 20 heads of 6-month-old large white pigs were used, which were delivered to the meat processing enterprise for slaughter. All half carcasses were cooled in a refrigerating chamber using showering, 1 hour later they were divided into 2 groups: control (without treatment) and experimental with the final treatment with a suspension of lactic acid bacteria of the SafePro® B-2 strain (Lactobacillus sakei). It has been found that cooling of pork half-carcasses in a refrigerating chamber with stiving and final processing by a culture suspension of lactic-acid microorganisms of strain SafePro® B-2 (Lactobacillus sakei) on the 4th day of storage had a positive effect on the microscopic structure of the pork neck and was characterized by a uniform color distribution when histologic specimens of muscular tissue are colored with hematoxylin and eosin, and minor cracks in the sarcoplasm, preservation of transverse and longitudinal striation of muscular fibers in comparison with that of the unprocessed pork half-carcasses with cultures of lactic-acid microorganisms. The microscopic structure of the muscular tissue of the pork half-carcass neck after cooling with stiving and final processing by a culture of lactic-acid microorganisms of strain SafePro® B-2 for 7 days of storage had a more distinct histoarchitecture in comparison with that of the unprocessed pork half-carcasses, as well as was characterized by insignificant areas of muscular fibers with transverse cracks, suspended development period of autolysis processes, partial preservation of transverse and longitudinal striation of muscle fibers. This points to a positive effect of lactic acid bacteria of strain SafePro® B-2 (Lactobacillus sakei) on the quality of the pork meat and contributes to the extension of its shelf life under chilled vintage.

Traditional spontaneously fermented foods are well known for their sensory and safety properties, which is mainly due to their indigenous microflora. Within this group of food, Mediterranean dry-cured sausages stand out as a significant source of lactic-acid bacterial strains (LAB) with biotechnological properties, such as their antimicrobial activity. The aim of this study was to investigate the biodiversity of antagonistic LAB strains from different Andalusian traditional sausages, such as salchichón and chorizo. First, a screening was carried out focusing on the antimicrobial activity against foodborne pathogens, such as Listeria monocytogenes, Escherichia coli, Clostridium perfringens, and Staphylococcus aureus, selecting two strains due to their higher antibiosis properties, both in agar and liquid media. These bacteria were identified as Lactiplantibacillus paraplantarum BPF2 and Pediococcus acidilactici ST6. In addition, genomic studies confirmed the presence of certain structural genes related to the production of bacteriocins. Finally, the culture supernatants of both strains were purified and analyzed by LC-MS/MS, obtaining the relative molecular mass and the amino acid sequence and identifying the peptides as the bacteriocins Pediocin-PA and Leucocin K. In conclusion, genomes and antimicrobial substances of P. acidilactici ST6, a Pediocin-PA producer, and Lpb. paraplantarum BPF2, a Leucocin K producer, isolated from Andalusian salchichón and chorizo, respectively, are presented in this work. Although further studies are required, these strains could be used alone or in combination as starters or protective cultures for the food industry. [ABSTRACT FROM AUTHOR]

This scientific paper determined the microbiological quality of Macedonian white brined cheese. Four best variants of Macedonian white brined cheeses were analysed for their microbiological parameters. From pathogenic microflora the following parameters were examined: a total number of: Coliforms, E. coli, pathogenic staphylococci, Molds, Yeast, Listeria and Salmonella. From lactic acid bacteria the following parameters were examined: the total number of Lactococcus bacteria and the total number of Lactobacillus bacteria. In all examined cheese samples pathogenic bacteria were not detected. Lactococcus bacteria was dominant bacteria in all four cheese variants at the beginning of ripening period till day 20. After that and at the end of ripening period (60 day) the Lactobacillus bacteria were predominant. [ABSTRACT FROM AUTHOR]

Microstructural changes in meat that occur during refrigerated storage depend on the hygiene of slaughtering and primary processing of animal carcasses, their cooling conditions, storage period, and microbial contamination and reflect the processes of meat maturation and spoilage. To extend the shelf life of pork in half-carcasses in a chilled state, 20 heads of 6-month-old large white pigs were used, which were delivered to the meat processing enterprise for slaughter. All half carcasses were cooled in a refrigerating chamber using showering, 1 hour later they were divided into 2 groups: control (without treatment) and experimental with the final treatment with a suspension of lactic acid bacteria of the SafePro® B-2 strain (Lactobacillus sakei). It has been found that cooling of pork half-carcasses in a refrigerating chamber with stiving and final processing by a culture suspension of lactic-acid microorganisms of strain SafePro® B-2 (Lactobacillus sakei) on the 4th day of storage had a positive effect on the microscopic structure of the pork neck and was characterized by a uniform color distribution when histologic specimens of muscular tissue are colored with hematoxylin and eosin, and minor cracks in the sarcoplasm, preservation of transverse and longitudinal striation of muscular fibers in comparison with that of the unprocessed pork half-carcasses with cultures of lactic-acid microorganisms. The microscopic structure of the muscular tissue of the pork half-carcass neck after cooling with stiving and final processing by a culture of lactic-acid microorganisms of strain SafePro® B-2 for 7 days of storage had a more distinct histoarchitecture in comparison with that of the unprocessed pork half-carcasses, as well as was characterized by insignificant areas of muscular fibers with transverse cracks, suspended development period of autolysis processes, partial preservation of transverse and longitudinal striation of muscle fibers. This points to a positive effect of lactic acid bacteria of strain SafePro® B-2 (Lactobacillus sakei) on the quality of the pork meat and contributes to the extension of its shelf life under chilled vintage. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine for the first time the microbiota in artisanal-type and industrial-type Gidotyri cheeses and investigate the influence of the cheese-making practices on their composition using culture-independent techniques. The microbiota present in artisanal with commercial starters (Artisanal_CS, n = 15), artisanal with in-house starters (Artisanal_IHS, n = 10) and industrial (Ind., n = 9) Gidotyri cheese samples were analyzed using a targeted metagenomic approach (16S rRNA gene). The Ind. Gidotyri cheese microbiota were less complex, dominated by the Streptococcaceae family (91%) that was more abundant compared to the artisanal Gidotyri cheeses (p < 0.05). Artisanal cheeses were more diverse compositionally with specific bacterial species being prevalent to each subtype. Particularly, Loigolactobacillus coryniformis (OTU 175), Secundilactobacillus malefermentans (OTU 48), and Streptococcus parauberis (OTU 50) were more prevalent in Artisanal_IHS cheeses compared to Artisanal_CS (p ≤ 0.001) and Ind. (p < 0.01) Gidotyri cheeses. Carnobacterium maltaromaticum (OTU 23) and Enterobacter hormaechei subsp. hoffmannii (OTU 268) were more prevalent in Artisanal_CS cheeses compared to Artisanal_IHS cheeses (p < 0.05) and Ind. cheeses (p < 0.05). Hafnia alvei (OTU 13) and Acinetobacter colistiniresistens (OTU 111) tended to be more prevalent in Artisanal_CS compared to the other two cheese groups (p < 0.10). In conclusion, higher microbial diversity was observed in the artisanal-type Gidotyri cheeses, with possible bacterial markers specific to each subtype identified with potential application to traceability of the manufacturing processes' authenticity and cheese quality. [ABSTRACT FROM AUTHOR]

Traditional spontaneously fermented foods are well known for their sensory and safety properties, which is mainly due to their indigenous microflora. Within this group of food, Mediterranean dry-cured sausages stand out as a significant source of lactic-acid bacterial strains (LAB) with biotechnological properties, such as their antimicrobial activity. The aim of this study was to investigate the biodiversity of antagonistic LAB strains from different Andalusian traditional sausages, such as salchichón and chorizo. First, a screening was carried out focusing on the antimicrobial activity against foodborne pathogens, such as Listeria monocytogenes, Escherichia coli, Clostridium perfringens, and Staphylococcus aureus, selecting two strains due to their higher antibiosis properties, both in agar and liquid media. These bacteria were identified as Lactiplantibacillus paraplantarum BPF2 and Pediococcus acidilactici ST6. In addition, genomic studies confirmed the presence of certain structural genes related to the production of bacteriocins. Finally, the culture supernatants of both strains were purified and analyzed by LC-MS/MS, obtaining the relative molecular mass and the amino acid sequence and identifying the peptides as the bacteriocins Pediocin-PA and Leucocin K. In conclusion, genomes and antimicrobial substances of P. acidilactici ST6, a Pediocin-PA producer, and Lpb. paraplantarum BPF2, a Leucocin K producer, isolated from Andalusian salchichón and chorizo, respectively, are presented in this work. Although further studies are required, these strains could be used alone or in combination as starters or protective cultures for the food industry.

The dark fermentation process was evaluated for biohydrogen production from food waste through fungal solid-state fermentation (SSF). Three fungal cultures (one strain of Aspergillus tubingensis and two strains of Meyerozyma caribbica) were compared, being A. tubingensis the best hydrolyser culture for releasing soluble carbohydrates. The biochemical hydrogen potential of food waste hydrolysate (FWH) at different substrate-inoculum ratios obtained a lower hydrogen yield than untreated food waste (RFW). The highest hydrogen yield value corresponded to treatments RFW-20 and RFW-30 with 77.0 ± 2.6 and 76.9 ± 1.4 mL H 2 normalized by per gram volatile solid added (NmL H 2 /gVS added), respectively. The microbial community of food waste was analysed, being detected lactic-acid bacteria genera as Latilactobacillus and Leuconostoc. The presence of actively growing bacteria during the SSF could explain the lowest hydrogen yield (20.1–36.0 NmL H 2 /gVS added) in the FWH treatment due to the substrate competition between lactic-acid bacteria and hydrogen-producing bacteria, where the lactic-acid bacteria were favoured by their faster growth rate. • The fungal solid-state fermentation of food waste using A. tubingensis increased the released carbohydrates. • The presence of indigenous lactic-acid bacteria from food waste could affect H 2 production. • Food waste hydrolysate with A. tubingensis obtained a lower H 2 yield than control. • The use of fungal solid-state fermentation decreased the lag phase of the dark fermentation process. [ABSTRACT FROM AUTHOR]

The by-products of the food industry are an economic alternative as a source of nutrients to obtain biomass. At the same time, theiruse could solve the environmental problem related to their disposal, which is highly polluting due to their elevated biochemical oxygen demand. In this work, we seek to optimize the production of cellular biomass of two native Patagonian strains of Lactiplantibacillus plantarum (UNQLp 11 and UNQLp155), selected for its oenological and technological properties, using apple pomace (AP), a residue from the juice and cider industry. The supplementation of AP with yeast extract, salts, and Tween 80 (sAP), proved to maintain the growth of the Lpb. plantarum strains, similar to the commercial medium used to grow LAB (De Man, Rogosa, Sharpe, MRS). Cultures grown in sAP medium showed good tolerance to wine conditions (high ethanol content and low pH), demonstrated by its ability to consume L-malic acid. The subsequent inoculation of these cultures in sterile wines (Merlot and Pinot noir) was carried out at laboratory scale, evaluating cell viability and L-malic acid consumption for 21 days at 21 °C. Cultures grown in sAP media showed a similar performance to MRS media. Thus, sAP media proved to be a suitable substrate to grow oenological Lpb. plantarum strains where cultures (with high size inoculums) were able to drive malolactic fermentation, with an L-malic acid consumption higher than 90%. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine for the first time the microbiota in artisanal-type and industrial-type Gidotyri cheeses and investigate the influence of the cheese-making practices on their composition using culture-independent techniques. The microbiota present in artisanal with commercial starters (Artisanal_CS, n = 15), artisanal with in-house starters (Artisanal_IHS, n = 10) and industrial (Ind., n = 9) Gidotyri cheese samples were analyzed using a targeted metagenomic approach (16S rRNA gene). The Ind. Gidotyri cheese microbiota were less complex, dominated by the Streptococcaceae family (91%) that was more abundant compared to the artisanal Gidotyri cheeses (p < 0.05). Artisanal cheeses were more diverse compositionally with specific bacterial species being prevalent to each subtype. Particularly, Loigolactobacillus coryniformis (OTU 175), Secundilactobacillus malefermentans (OTU 48), and Streptococcus parauberis (OTU 50) were more prevalent in Artisanal_IHS cheeses compared to Artisanal_CS (p ≤ 0.001) and Ind. (p < 0.01) Gidotyri cheeses. Carnobacterium maltaromaticum (OTU 23) and Enterobacter hormaechei subsp. hoffmannii (OTU 268) were more prevalent in Artisanal_CS cheeses compared to Artisanal_IHS cheeses (p < 0.05) and Ind. cheeses (p < 0.05). Hafnia alvei (OTU 13) and Acinetobacter colistiniresistens (OTU 111) tended to be more prevalent in Artisanal_CS compared to the other two cheese groups (p < 0.10). In conclusion, higher microbial diversity was observed in the artisanal-type Gidotyri cheeses, with possible bacterial markers specific to each subtype identified with potential application to traceability of the manufacturing processes’ authenticity and cheese quality.

We aimed to assess efficiency of various anti-microbe effects on pathogenic microflora; to do that, we performed com-parative study on how sensitive Campylobacter jejuni test strains were to ultraviolet radiation and biocides based on peracetic acid (PAA). PAA-based biocides suppressed significant numbers of Campylobacter; however, preset treating modes didn’t allow achieving complete inactivation of the test strains. Efficiency of effects produced by ultraviolet radiation on C.jejuni strains depended on exposure duration: 20-minute treatment of plates with broth bacterial suspensions caused a decrease in a number of viable cells which was equal to 1.5–2,0 logarithmic orders; 60-minute treatment resulted in a decrease in C.jejuni contents that amounted to less than 200 CFU/cm3. Polypeptide antibiotics produced by lactic-acid bacteria (bacteriocins, nisin, etc.) have some useful properties and it makes them applicable for suppressing adverse microflora in food products manufacture. We applied an ‘associate growth” model to examine peculiarities related to C.jejuni growth in milk that, beside this pathogen, was simultaneously inoculated with mesophilic lactic-acid lactococci or thermophilic lactic-acid bacteria that were bacteriocins producers. Depending on quantity of introduced lactic-acid bacteria, such as Lactobacillusplantarum, Lactobacilluslactis and Lactococcuslactis, C.jejuni growth was substantially inhibited. We revealed a relationship between anti-bacterial activity and nature of inhibiting effects and concentrations of the above-mentioned lactic-acid microorganisms, temperature, an amount of time during mixed cultures were cultivated together, and properties of used strains which became the most apparent when lactobacteria were introduced in a dose equal to 108 CFU/cm3. Our study on an ability of C.jejuni to survive under exposure to an adverse environment revealed that microbe populations had variable physiological properties, Campylobacter were greatly resistant, and it was difficult to make a relevant choice on efficient tools and procedures for anti-microbe treatment.

The aim of the present study was to determine the efficacy of LAB strains in reducing the intestinal toxicity of arsenite [As(III)] and its tissue accumulation. For this purpose, Balb/c mice were randomly separated in four groups. One group received no treatment (control), one group received only As(III) (30 mg/L) via drinking water and the remaining two groups received As(III) via water and a daily dose of two LAB strains (Lactobacillus intestinalis LE1 and Lacticaseibacillus paracasei BL23) by gavage during 2 months. The results show that both strains reduce the pro-inflammatory and pro-oxidant response observed at the colonic level, partially restore the expression of the intercellular junction proteins (CLDN3 and OCLN) responsible for the maintenance of epithelial integrity, and increase the synthesis of the major mucin of the colonic mucus layer (MUC2), compared to animals treated with As(III) alone. Microbial metabolism of short-chain fatty acids also undergoes a recovery and the levels of fatty acids in the lumen reach values similar to those of untreated animals. All these positive effects imply the restoration of mucosal permeability, and a reduction of the marker of endotoxemia LPS binding protein (LBP). Treatment with the bacteria also has a direct impact on intestinal absorption, reducing the accumulation of As in the internal organs. The data suggest that the protective effect may be due to a reduced internalization of As(III) in intestinal tissues and to a possible antioxidant and anti-inflammatory activity of the bacteria through activation of pathways such as Nrf2 and IL-10. In vitro tests show that the protection may be the result of the combined action of structural and metabolic components of the LAB strains. • Lactic acid bacteria (LAB) reduce intestinal toxicity caused by As exposure. • LAB reduce structural and functional alterations caused by As in colonic tissue. • LAB may protect reducing intestinal accumulation or activating some signaling pathways. • The protection may be a combined action of structural and metabolic LAB components. • LAB administration also reduces accumulation of As in internal target organs. [ABSTRACT FROM AUTHOR]

Using whey, a by-product of the cheese-making process, is important for maximizing resource efficiency and promoting sustainable practices in the food industry. Reusing whey can help minimize environmental impact and produce bio-preservatives for foods with high bacterial loads, such as Mexican-style fresh cheeses. This research aims to evaluate the antimicrobial and physicochemical effect of CFS from Lactobacillus casei 21/1 produced in a conventional culture medium (MRS broth) and another medium using whey (WB medium) when applied in Mexican-style fresh cheese inoculated with several indicator bacteria ( Escherichia coli , Salmonella enterica serovar Typhimurium, Staphylococcus aureus , and Listeria monocytogenes ). The CFSs (MRS or WB) were characterized for organic acids concentration, pH, and titratable acidity. By surface spreading, CFSs were tested on indicator bacteria inoculated in fresh cheese. Microbial counts were performed on inoculated cheeses during and after seven days of storage at 4 ± 1.0 °C. Moreover, pH and color were determined in cheeses with CFS treatment. Lactic and acetic acid were identified as the primary antimicrobial metabolites produced by the Lb. casei 21/1 fermentation in the food application. A longer storage time (7 days) led to significant reductions ( p < 0.05) in the microbial population of the indicator bacteria inoculated in the cheese when it was treated with the CFSs (MRS or WB). S. enterica serovar Typhimurium was the most sensitive bacteria, decreasing 1.60 ± 0.04 log 10 CFU/g with MRS-CFS, whereas WB-CFS reduced the microbial population of L. monocytogenes to 1.67 log 10 CFU/g. E. coli and S. aureus were the most resistant at the end of storage. The cheese's pH with CFSs (MRS or WB) showed a significant reduction ( p < 0.05) after CFS treatment, while the application of WB-CFS did not show greater differences in color (ΔE) compared with MRS-CFS. This study highlights the potential of CFS from Lb. casei 21/1 in the WB medium as an ecological bio-preservative for Mexican-style fresh cheese, aligning with the objectives of sustainable food production and guaranteeing food safety.

This research purpose is to develop functional products from biomodified low-grade by-products and waste using microorganism consortia. To create conditions for a balanced diet and improve the health of the population, the technique of using biotechnological methods directed at attracting non-traditional resources was proposed. The object of the study was secondary meat by-products and waste from the meat processing industry. The meat products and waste were processed with such lactic-acid bacteria as Lactobacillus bulgaricus, Bifidumbacterinum siccum, and Staphilococcus carnosus. Lactic-acid bacteria were cultured step-by-step in different combinations: Staphilococcus carnosus and Lactobacillus bulgaricus; Bifidumbacterinum siccum and Staphilococcus carnosus; Lactobacillus bulgaricus and Bifidumbacterinum siccum. Changes in the growth activity of selected species of lactic-acid bacteria in various combinations were carried out in various nutrient media. When growing the studied strains in a medium of meat-and-peptone agar, their complete identification was carried out. The final stage was the analysis of the quality of real objects: horse meat, flank, and standard beef muscle tissue. The dynamics of changes in indicators of functional and technological and organoleptic meat properties proved a positive effect from the use of lactic acid bacteria. Developed races have shown the ability to suppress harmful microflora in meat products actively. Moreover, they softened the secondary meat for processing and positively proved to improve the finished product's organoleptic characteristics. Processing of secondary resources of by-products and waste will allow more economical and rational use of the most essential collagen-containing food reserve of meat and meat products. The insufficient coverage of this issue on the use of a combined strain of these species of microorganisms for the biomodification of secondary collagen-containing by-products and waste in the meat industry indicates the relevance of the chosen topic.. [ABSTRACT FROM AUTHOR]

The by-products of the food industry are an economic alternative as a source of nutrients to obtain biomass. At the same time, theiruse could solve the environmental problem related to their disposal, which is highly polluting due to their elevated biochemical oxygen demand. In this work, we seek to optimize the production of cellular biomass of two native Patagonian strains of Lactiplantibacillus plantarum (UNQLp 11 and UNQLp155), selected for its oenological and technological properties, using apple pomace (AP), a residue from the juice and cider industry. The supplementation of AP with yeast extract, salts, and Tween 80 (sAP), proved to maintain the growth of the Lpb. plantarum strains, similar to the commercial medium used to grow LAB (De Man, Rogosa, Sharpe, MRS). Cultures grown in sAP medium showed good tolerance to wine conditions (high ethanol content and low pH), demonstrated by its ability to consume L-malic acid. The subsequent inoculation of these cultures in sterile wines (Merlot and Pinot noir) was carried out at laboratory scale, evaluating cell viability and L-malic acid consumption for 21 days at 21 °C. Cultures grown in sAP media showed a similar performance to MRS media. Thus, sAP media proved to be a suitable substrate to grow oenological Lpb. plantarum strains where cultures (with high size inoculums) were able to drive malolactic fermentation, with an L-malic acid consumption higher than 90%.

Salmonella enterica serovar Typhimurium is a pervasive enteric pathogen and ongoing global threat to public health. Ecological studies in the Salmonella impacted gut remain underrepresented in the literature, discounting microbiome mediated interactions that may inform Salmonella physiology during colonization and infection. To understand the microbial ecology of Salmonella remodeling of the gut microbiome, we performed multi-omics on fecal microbial communities from untreated and Salmonella-infected mice. Reconstructed genomes recruited metatranscriptomic and metabolomic data providing a strain-resolved view of the expressed metabolisms of the microbiome during Salmonella infection. These data informed possible Salmonella interactions with members of the gut microbiome that were previously uncharacterized. Salmonella-induced inflammation significantly reduced the diversity of genomes that recruited transcripts in the gut microbiome, yet increased transcript mapping was observed for seven members, among which Luxibacter and Ligilactobacillus transcript read recruitment was most prevalent. Metatranscriptomic insights from Salmonella and other persistent taxa in the inflamed microbiome further expounded the necessity for oxidative tolerance mechanisms to endure the host inflammatory responses to infection. In the inflamed gut lactate was a key metabolite, with microbiota production and consumption reported amongst members with detected transcript recruitment. We also showed that organic sulfur sources could be converted by gut microbiota to yield inorganic sulfur pools that become oxidized in the inflamed gut, resulting in thiosulfate and tetrathionate that support Salmonella respiration. This research advances physiological microbiome insights beyond prior amplicon-based approaches, with the transcriptionally active organismal and metabolic pathways outlined here offering intriguing intervention targets in the Salmonella-infected intestine., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

An oil-in-water emulsion stabilized with goat milk proteins was subjected to processing from lactic acid bacteria fermentation and the effects on emulsion microstructure and droplet characteristics were investigated. Optical microscopy and Turbiscan analyses were used to monitor the microstructure and droplet size during the fermentation. pH-driven effects led to milk protein conformational changes as indicated by the determination of total thiol groups and affected the protein interfacial composition. This phenomenon coincided (pH<5.5, T>37.9 °C) with the increase in average droplet size, which was attributed to flocculation phenomena due to reduced electrostatic repulsion. Casein solubility was enhanced during the initial stages of fermentation (1 h - 3 h) and was precipitated at pH < 4.8. LC-MS/MS analysis confirmed that caseins (α s1-, α s2 -, β- and κ-casein) were the dominant protein species at oil-water interface at the end of the fermentation process and contributed to the stability of the emulsion by reducing the droplet diameter (1.24 μm). • Oil-in-water emulsions made with goat milk were fermented with lactic-acid bacteria. • The oil droplet size was reduced after the fermentation (1.41 ± 0.02μm-1.24 ± 0.03 μm). • Caseins were the dominant protein species at the interface at the end of processing. • pH may induce conformational changes of goat milk proteins during fermentation. [ABSTRACT FROM AUTHOR]

Improving the quality indicators of meat products is associated with the targeted use of microorganisms, which contributes to obtaining a stable quality of the finished product. The article discusses the impact of various starter cultures on the bio-and physico-chemical changes, structural and mechanical, organoleptic and functional and technological parameters, as well as the microflora of the product. The various methods of application of starter in the technology of meat products is widely described. The role of starter cultures, including lactic acid bacteria in the formation of the structure and consistency, increasing the content of lactic and volatile fatty acids, free amino acids and improving the taste and flavor of meat products is especially noted. [ABSTRACT FROM AUTHOR]

Cereal-based probiotic products are increasingly gaining the interest of consumers prioritizing healthier lifestyle choices. Oat grain (Avena sativa L.) is a cereal crop valued for its balanced nutritional composition and the numerous functional compounds it contains, including ß-glucan and avenanthramides. The objective of this study was to research the potential of oat flour for preparing cereal-based probiotic drinks. After the analysis of ß- glucan content and antioxidant activity of several oat flour types, Bulgarian heat-treated whole grain oat flour with 4.63% ß-glucan content and high antioxidant capacity was selected for the study. As viscosity of drinks is one of their major characteristics, analysis was made of the rheological behaviour of oat suspensions with concentrations of 4%, 5% and 6% (wt/v) at temperatures of 70°C, 75°C, 80°C. The following parameters were selected: temperature and time mode: 8 minutes at 75°C for 6% flour concentration. Starter cultures of the probiotic strains Lactobacillus plantarum BB2 and Lactobacillus plantarum Pro were used for the fermentation of the heat-treated suspension. Besides their proven probiotic properties, both strains have amylolytic activity which plays a critical role in cereal substrates. A controlled fermentation with these monocultures was conducted at 37°C for a period of 8 hours. pH, total viable count lactic-acid bacteria, α-amylase activity as well as changes in the rheological characteristics of the drink were periodically reported throughout the fermentation process. At the end of the 8-hour period the target values of the studied parameters were reached. The results of the conducted analyses showed that whole grain oat flour is a suitable substrate for the growth of probiotic lactic-acid bacteria under the selected fermentation conditions. [ABSTRACT FROM AUTHOR]