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Cheese preservation has become a major issue for the global cheese industry due to microbial spoilage and the effects of chemical preservatives on human health. Consumer health and environmental awareness have motivated researchers to introduce cheese products that contemplate safety, minimal processing, eco-labels, and clean labels. Preservation strategies include a) advanced technologies comprising non-thermal processing (high pressure, cold plasma, pulsed light, ultrasound) and packaging technologies (bioactive films, coating, and modified atmospheric packaging), b) direct incorporation of natural antimicrobial agents, such as mycocins, endolysins, lactic acid bacteria and their bacteriocins and c) application of various plant extracts, essential oils and propolis. Advanced technologies have shown broad-spectrum antimicrobial action with a minimal adverse effect on cheese quality. Methods such as the direct addition of plant extracts negatively affect cheese texture, sensory and physicochemical properties. However, encapsulated and film forms are known to minimize these drawbacks. This review comprehends the sustainable cheese preservation strategies, their effectiveness in shelf-life extension, and physiochemical and quality attributes of cheese post-preservation. Overall, this review can benefit the cheese industry by enhancing market value, consumer satisfaction, and environmental well-being. • Sustainable strategies have shown substantial efficiency in cheese preservation. • Nonthermal processing and active packaging, have minimal adverse effects on cheese quality attributes. • Plant extract and propolis improve safety but may interfere with the sensory and textural properties of cheese. • Combining advanced technology with appropriate natural antimicrobial agents contributes to efficient preservation. • Examination of physicochemical properties have been established to validate the efficacy of preservation methods. [ABSTRACT FROM AUTHOR]

BACKGROUND The antioxidant and antibacterial activities of fermented sarshir (traditional dairy food), with three probiotic Lactobacillus plantarum strains (LP3, AF1, and LU5), were investigated. The oxidative stability and the lipid profile of non-fermented and fermented sarshir were compared, in addition to radical scavenging activity, as well as peroxide, anisidine and carbonyl values (PV, AnV and CV, respectively). RESULTS The strong antibacterial activity of fermented sarshir against common pathogenic bacteria, including Gram-negative Escherichia coli O157: H7 ATCC 35150 and Pseudomonas aeruginosa ATCC 27853, as well as Gram-positive Bacillus cereus ATCC 10876 and Staphylococcus aureus ATCC 25923, was established. Among the strains examined, L. plantarum LP3 exhibited the highest radical scavenging activity (53.1 ± 1.8%) and lowest PV (3.0 meq kg-1), AnV (1.31 ± 0.06) and CV (1.4 ± 0.08). The pH of sarshir decreased from 6.2 ± 0 to 3.5 ± 0.1 during 14 h of fermentation. Incorporated bacterial cells exhibited notable viability during 10 days of cold storage (4 °C). CONCLUSION The fermentation of sarshir by L. plantarum strains, especially LP3, resulted in beneficial changes in radical scavenging activity, as well as PV, AnV and carbonyl values, in addition to a broad spectrum of inhibitory activity against strains of P. aeruginosa, E. coli O157:H7, B. cereus and S. aureus. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The bioethanol visibility in the global matrix of fuels, linked to ecological appeal and the possibility of using new raw materials justifies the increasing investments for the development of new processes. This fuel results from fermentation of sugars by yeasts, however the growth of exogenous microorganisms is sometimes unavoidable. The lactic acid bacteria and wild yeasts are the main contaminants, affecting yeasts’ performance and leading to negative impacts such as the formation of organic acids, polysaccharides and gummy biofilms. Further undesirable effects of the microbial contamination during bioethanol processing comprise flocculation, reduction of yeast cells viability and decrease in process yield. In extreme cases, the reduction in process yield can reach 20–30%, making the process impracticable. In this article, the impact and significance of microbial contaminants (lactic acid bacteria and wild yeasts) during fermentation of must for bioethanol production are reviewed. [ABSTRACT FROM AUTHOR]

This study aimed to enumerate and identify lactic acid bacteria and Enterobacteriaceae from spoiled and nonspoiled chilled vacuum-packaged beef and determine their potential to cause blown pack spoilage. These microbial groups were also enumerated in nonspoiled samples and detected in abattoir samples. The potential of isolates to cause 'blown pack' spoilage of vacuum-packaged beef stored at chilled temperature (4 °C) and abuse temperature (15 °C) was investigated. Populations of lactic acid bacteria in exudate of spoiled and nonspoiled samples were not significantly different ( P > 0.05), whereas the number of lactic acid bacteria on the surface was significantly higher ( P < 0.05) in spoiled samples as compared to nonspoiled samples. The population of Enterobacteriaceae species in exudate and on the surface of samples were significantly higher ( P < 0.05) in spoiled packs in comparison with nonspoiled packs. Results of the deterioration potential showed that 'blown pack' spoilage was noticeable after 7 days at 15 °C and after 6 weeks at 4 °C for samples inoculated with Hafnia alvei. [ABSTRACT FROM AUTHOR]

Abstract: Growth potential (δ) is defined as the difference between the population of a microorganism at the end of shelf-life of specific food and its initial population. The determination of δ of Salmonella and Listeria monocytogenes in RTE vegetables can be very useful to determine likely threats to food safety. However, little is known on the behavior of these microorganisms in several RTE vegetables. Therefore, the aim of this study was to determine the δ of both pathogens in nine different types of RTE vegetables (escarole, collard green, spinach, watercress, arugula, grated carrot, green salad, and mix for yakisoba) stored at refrigeration (7°C) and abuse temperature (15°C). The population of aerobic microorganisms and lactic acid bacteria, including those showing antimicrobial activity has been also determined. Results indicated that L. monocytogenes was able to grow (δ ≥0.5 log10) in more storage conditions and vegetables than Salmonella. Both microorganisms were inhibited in carrots, although a more pronounced effect has been observed against L. monocytogenes. The highest δ values were obtained when the RTE vegetables were stored 15°C/6days in collard greens (δ =3.3) and arugula (δ =3.2) (L. monocytogenes) and arugula (δ =4.1) and escarole (δ =2.8) (Salmonella). In most vegetables and storage conditions studied, the counts of total aerobic microorganisms raised significantly independent of the temperature of storage (p <0.05). Counts of lactic acid bacteria were higher in vegetables partially or fully stored at abuse temperature with recovery of isolates showing antimicrobial activity. In conclusion, the results of this study show that Salmonella and L. monocytogenes may grow and reach high populations in RTE vegetables depending on storage conditions and the definition of effective intervention strategies are needed to control their growth in these products. [Copyright &y& Elsevier]

Higher resistance of microbial spores to high temperatures, low pH and high pressures coupled with characteristics such as good stability and rapid germination make their use extremely desirable for the innovative formulation of several probiotic foods, mainly due to the inherent technological limitations of lactic acid bacteria (LAB), which represent the main probiotic microorganisms applied in food. Probiotic spores are resistant to several processing conditions employed in the food industry, thus presenting high feasibility of application and guaranteeing the functionality of probiotic foods; in addition, they are able to maintain such characteristics throughout the shelf life of such products stored at room temperature or under refrigeration. This study presents a review of the main characteristics, technological implications, and types of consumption and health benefits of potential probiotic Bacillus spores. Spore-forming probiotics are available in different pharmaceutical forms (sachets, capsules, tablets, pills, liquid suspensions) and used in medical and veterinary fields, and more recently in the food industry. Health benefits of spore-forming probiotics should be intensively studied, evaluating their behavior in the GIT and other anatomical sites, determining the mechanisms of action involved and correlating them with the main beneficial effects on health. Spore-forming probiotics have great potential for applications in the food industry, since they present high resistance to the technological processes and physiological mechanisms of the body, which would be lethal to LAB. • Probiotic lactic acid bacteria cannot be used in all types of foods. • Bacillus probiotics are resistant to food processing conditions. • Technological implications and benefits of probiotic Bacillus are discussed. [ABSTRACT FROM AUTHOR]

This study aimed to assess the behavior of endogenous microbiota (total mesophilic and psychrotrophic bacteria) during the ripening period and of L. monocytogenes and lactic acid bacteria (LAB) during storage at 5, 10, and 20 °C of artisanal Canastra cheeses packed in a silver nanoparticles packaging system using a predictive modeling approach. The tested packaging system did not influence the initial values of pH (around 5.0) or aw (around 0.95) over the storage. Based on the mathematical parameters obtained by the Weibull predictive model, the active packaging system tested did not inactivate L. monocytogenes during the storage period of artisanal Canastra cheeses. Nonetheless, the findings indicate that the polyethylene packaging system containing silver nanoparticles (3000 ppm active based on silicon dioxide and silver) did not affect endogenous bacteria of Canastra cheese during ripening and storage, which opens the opportunity for the use of this material without compromising the role of these bacteria during cheese ripening, contributing to characteristics of the product's identity. • Silver nanoparticle pack (SNP) did not kill L. monocytogenes over cheese storage. • SNP did not affect endogenous bacteria of the cheese during ripening and storage. • SNP can be used to avoid recontamination of cheese thru ripening and further steps. [ABSTRACT FROM AUTHOR]

The loss of probiotics viability in yogurts and fermented milk is a significant challenge in producing yogurt and fermented milk. Thus, pre-exposure of probiotics to stress conditions can be a viable alternative to increase the probiotic viability. Moreover, the use of fruit pulp and agro-industrial residues in these products has demonstrated promising results in promoting growth and improving the viability of probiotics. Thus, this study aimed to evaluate the effects of pre-exposure to acid, oxidative and osmotic stress on the growth and viability of Lactobacillus acidophilus in yogurts and naturally fermented milk containing buriti (Mauritia flexuosa Mart.) pulp or orange byproduct. L. acidophilus was individually pre-exposed to acid, oxidative, and osmotic stress and used in the production of yogurts and fermented milk to determine both the acidification profile and growth of the cultures. Furthermore, during cold storage, the post-acidification profiles and viability of microbial cultures added to the yogurts and fermented milk were monitored. Results showed that pre-exposure to stress conditions influenced the growth parameters as the growth rate (μ) and lag phase (λ) of L. acidophilus and the starter cultures of S. thermophilus and L. delbrueckii subsp. bulgaricus. Moreover, an increase in the viability of L. acidophilus - pre-exposed to acid stress - was observed on the 21st day of storage of natural yogurts containing orange byproduct compared with non-stressful conditions. This study reports new data on the growth of probiotic cultures pre-exposed to stress conditions in products added of pulps and agro-industrial residues, which have not yet been shown in the literature. • Pre-exposure to acidic, oxidative, and osmotic stress impacts L. acidophilus (La) growth during milk fermentation. • The pre-exposure of L. acidophilus to stressful conditions influences starter culture growth during yogurt production. • Survival of L. acidophilus under acid stress before exposure in yogurts with orange by-product during 21 days of cold storage. • Orange byproduct and buriti pulp promote probiotic growth during fermented milk production. [ABSTRACT FROM AUTHOR]

• Natural preservatives are alternatives for improving seafood quality and safety. • Essential oils, bacteriocins, organic acids and chitosan applications were revised. • Combined treatments with other technologies enhance natural products effectivity. • Mistures of natural compounds with potentialized preservative activities is rare. Seafood is highly perishable, presenting a rapid loss of its quality soon after capture. Temperature is the critical parameter that impacts on seafood shelf-life reduction, allowing the growth of foodborne pathogens and spoilage microorganisms. In recent years, the search by additional methods of preserving seafood has increased, able to ensure quality and safety. Several natural preservatives have highlighted and gained considerable attention from the scientific community, consumers, industry, and health sectors as a method with broad action antimicrobial and generally economical. Natural preservatives, from different sources, have been widely studied, such as chitosan from animal sources, essential oils, and plant extracts from a plant source, lactic acid bacteria, and bacteriocins from microbiological sources and organic acid from different sources, all with great potential for use in seafood systems. This review focuses on the natural preservatives studied in seafood matrices, their forms of application, concentrations usually employed, their mechanisms of action, factors that interfere in their use and the synergistic effect of the interactions among the natural preservatives, with a focus for maintenance of quality and ensure of food safety. [ABSTRACT FROM AUTHOR]

In this study a total of 220 isolates of lactic acid bacteria (LAB) recovered from 10 types of Brazilian artisanal cheeses marketed in 4 main regions of Brazil were evaluated regarding their safety and ability to produce diacetyl (a precursor of aromatic compounds), exopolysaccharides (EPS; from different sugar sources), and antagonistic activity against Listeria monocytogenes and Staphylococcus aureus. The results indicated that 131 isolates (59.6%) were classified as strong (40.5%) and moderate (19.1%) diacetyl producers; 28 isolates (12.7%) stood out due to their remarkable production of EPS from different sugars, including sucrose (3.2%), fructose (2.3%), lactose (2.3%), and glucose (6%). Furthermore, 94.1% and 95.9% of isolates presented antagonistic activity against S. aureus and L. monocytogenes , respectively, even though only 27 isolates (12.3%) exhibited positive results in the bacteriocin production test. None of the isolates tested presented hemolytic activity, and 117 were classified as safe, due to their intrinsic resistance to a maximum of 4 different antibiotics. The data obtained for assessment of antibiogram profile and technological potential (moderate and high production of diacetyl, EPS, and bacteriocins) were submitted to a multiple correspondence analysis to correlate them with the cheese of isolation. Regarding the antimicrobial profile of LAB strains, it was possible to verify an association between isolates from Minas artisanal cheeses from Araxá and resistance to tetracycline; Minas artisanal cheeses from Serro and resistance to erythromycin; Coalho and Minas artisanal cheese from Cerrado and resistance to penicillin; and isolates from Serrano and Colonial cheeses with clindamycin and ceftazidime resistance. Although the susceptibility of strains to these antibiotics was considered high (71.8–80.5%), these data may be related to the horizontal transfer of genes in the production chain of these cheeses. Results of multiple correspondence analysis also showed that isolates with antagonistic activity were mostly isolated from Manteiga, Colonial, and Coalho cheeses. The isolates with high or moderate EPS-producer ability from sucrose, glucose, and fructose were mainly associated with Minas artisanal cheeses from Cerrado. In contrast, isolates with high or moderate EPS-producer ability from lactose were isolated from Serrano, Minas artisanal cheeses from Canastra, and Campo das Vertentes microregions. Finally, isolates from Minas artisanal cheeses (from Araxá microregion), Coalho, and Caipira cheeses were associated with moderate/high diacetyl production. To the best of the authors' knowledge, this study provides, for the first time, data indicating that the dominant technological, biopreservative, and safety properties of LAB isolates can be correlated with the type of Brazilian artisanal cheeses, which denotes its singularity. This knowledge is of utmost relevance for the development of starter or adjunct cultures with tailored properties. [ABSTRACT FROM AUTHOR]

Fungi are the main microorganisms responsible for the spoilage of bakery products, and their control and subsequent reduction of food waste are significant concerns in the agri-food industry. Synthetic preservatives are still the most used compounds to reduce bakery product spoilage. On the other hand, studies have shown that biopreservation can be an attractive approach to overcoming food and feed spoilage and increasing their shelf-life. However, limited studies show the preservation effects on real food matrices. Therefore, this study aimed to investigate the influence of microorganisms such as lactic acid bacteria (LAB) and yeasts on the growth of spoilage filamentous fungi (molds) on bread and panettones. In general, on conventional and multigrain bread, treatments containing Limosilactobacillus fermentum IAL 4541 and Wickerhamomyces anomalus IAL 4533 showed similar results when compared to the negative control (calcium propionate) in delaying the fungal growth of the tested species (Aspergillus chevalieri , Aspergillus montevidensis , and Penicillium roqueforti). Different from bread, treatments with W. anomallus in panettones delayed the A. chevalieri growth up to 30 days, 13 days longer than observed on negative control (without preservatives). This study showed that biopreservation is a promising method that can extend bakery products' shelf-life and be used as an alternative to synthetic preservatives. • Limosilactobacillus fermentum (Lif) and Wickerhamomyces anomalus (Wa) inhibit fungi. • Effects of Lf and Wa on shelf-life of sourdough breads and panettones • Four formulations assessed: control, regular (calcium propionate), F1 and F2 • Wa delayed the growth of spoilage fungi on panettone in up to 30 days. • Biopreservation can be a strategy the development of robust bakery formulations. [ABSTRACT FROM AUTHOR]

Abstract This study compares dynamic tertiary and competition models for L. monocytogenes growth as a function of intrinsic properties of a traditional Brazilian soft cheese and the inhibitory effect of lactic acid bacteria (LAB) during refrigerated storage. Cheeses were prepared from raw or pasteurized milk with or without the addition of selected LAB with known anti-listerial activity. Cheeses were analyzed for LAB and L. monocytogenes counts, pH and water activity (a w) throughout cold storage. Two approaches were used to describe the effect of LAB on L. monocytogenes : a Huang-Cardinal model that considers the effect of pH and a w variation in a dynamic kinetic analysis framework; and microbial competition models, including Lotka-Volterra and Jameson-effect variants, describing the simultaneous growth of L. monocytogenes and LAB. The Jameson-effect with γ and the Lotka-Volterra models produced models with statistically significant coefficients that characterized the inhibitory effect of selected LAB on L. monocytogenes in Minas fresh cheese. The Huang-Cardinal model [pH] outperformed both competition models. Taking a w change into account did not improve the fit quality of the Huang-Cardinal [pH] model. These models for Minas soft cheese should be valuable for future microbial risk assessments for this culturally important traditional cheese. Highlights • LAB with anti-listerial activity reduced the μ opt and Y max of L. monocytogenes. • Dynamic tertiary and competition models presented good fit quality. • Jameson-effect model with γ showed that LAB inhibited L. monocytogenes growth. • Lotka-Volterra model was significant for inhibition of L. monocytogenes. [ABSTRACT FROM AUTHOR]

Artisanal raw milk cheeses are highly appreciated dairy products in Brazil and ensuring their microbiological safety has been a great need. This study reports the isolation and characterization of lactic acid bacteria (LAB) strains with anti-listerial activity, and their effects on Listeria monocytogenes during refrigerated shelf-life of soft Minas cheese and ripening of semi-hard Minas cheese. LAB strains (n = 891) isolated from Minas artisanal cheeses (n = 244) were assessed for anti-listerial activity by deferred antagonism assay at 37 °C and 7 °C. The treatments comprised the production of soft or semi-hard Minas cheeses using raw or pasteurized milk, and including the addition of selected LAB only [ Lactobacillus brevis 2-392, Lactobacillus plantarum 1-399 and 4 Enterococcus faecalis (1-37, 2-49, 2-388 and 1-400)], L. monocytogenes only, selected LAB co-inoculated with L. monocytogenes , or without any added cultures. At 37 °C, 48.1% of LAB isolates showed anti-listerial capacity and 77.5% maintained activity at 7 °C. Selected LAB strains presented a bacteriostatic effect on L. monocytogenes in soft cheese. L. monocytogenes was inactivated during the ripening of semi-hard cheeses by the mix of LAB added. Times to attain a 4 log-reduction of L. monocytogenes were 15 and 21 days for semi-hard cheeses produced with raw and pasteurized milk, respectively. LAB with anti-listerial activity isolated from artisanal Minas cheeses can comprise an additional barrier to L. monocytogenes growth during the refrigerated storage of soft cheese and help shorten the ripening period of semi-hard cheeses aged at ambient temperature. [ABSTRACT FROM AUTHOR]

In this study, the use of soybean extract on production and physicochemical characteristics of kefir was assessed. Also, the growth parameters of yeasts and lactic acid bacteria (LAB) during fermentation were evaluated. Experiments were carried out combining water-soluble soybean extract (S) and milk (M), leading to the evaluation of total or partial replacement of milk (formulations 100%S, 50%S50%M) a control formulation (100%M). During kefir fermentation, physicochemical analysis carried out as well as enumeration of yeasts and LAB. In all formulations, lactic acid concentration increased due to carbohydrates consumption by kefir microorganisms resulting in decrease of soluble solids content and increase of acidity. The final acidity of beverages varied from 0.600 to 0.738 g of lactic acid/100 mL and soluble solids ranged from 6.40 to 5.67 °Brix. Formulations 100%S and 100%M presented LAB counts of 8 log 10  CFU/mL. LAB lag time increased in formulation 50%S50%M compared to formulations 100%S and 100%M (2.20 h, 1.03 h and 1.06 h, respectively). LAB and yeasts growth parameters were not affected in beverages prepared with milk and soybean kefir. This is the first study that examined the yeast and LAB growth parameters using water-soluble soybean extract fermented with kefir. [ABSTRACT FROM AUTHOR]

Background Cooked ready-to-eat (RTE) meat products are subjected to contamination of spoilage microorganisms such as lactic acid bacteria and pathogens such as Listeria monocytogenes . These microorganisms contaminate cooked RTE meat products after the cooking step and may further grow during shelf-life potentially leading to spoilage or foodborne diseases, respectively. In the current context of salt, fat and chemical preservatives reduction in meat products formulations, a combined strategy that considers the development of more robust formulations, active packaging and the use of non-thermal post-packaging decontamination strategies seems required to ensure shelf-stable and safe RTE cooked food products. Scope and approach The main objective of this review was to discuss the aspects related to reformulation, active packaging and the application of non-thermal decontamination technologies at the post-packaging step of cooked RTE meat products, their advantages, limitations and main challenges for their implementation. Key findings and conclusions In general, post-packaging decontamination technologies aim to reduce or inactivate pathogens and spoilage microorganisms present on the surface of ready-to-eat meat products. Low-temperature plasma, high-pressure processing (HPP), pulsed electric fields, pulsed ultraviolet light and ultrasound are promising alternatives in this segment. However, the choice of the most appropriate approach for post-packaging decontamination of cooked ready-to-eat meat products depends on the type of product and the technological objectives. Meat products formulation and packaging material properties should be considered while defining a post-packaging decontamination approach. Although they are advantageous, non-thermal technologies may present certain limitations such as the increase of oxidative reactions over the shelf-life. [ABSTRACT FROM AUTHOR]

This study aimed to determine the growth potential (δ) of L. monocytogenes (CLIST 3974, CLIST 3969, and CLIST 4162) and S. enterica [ S. Typhimurium (ATCC SM 14028), S. Enteritidis (SM 64), and S. Montevideo (SM 129)] in the presence of a pool of lactic acid bacteria (LAB) with antimicrobial activity in Frescal and semi-hard Minas microcheeses. The δ was determined after storing Frescal cheese at 4 and 7 °C for 15 days and the and semi-hard Minas cheese during ripening (22 °C for 22 days). The δ of L. monocytogenes was significantly higher in Frescal Minas cheese with no added LAB (p > 0.05). On the other hand, in semi-hard cheese inoculated with LAB, inactivation of L. monocytogenes was observed. No significant differences were found in the δ of S. enterica in Frescal Minas cheese inoculated with LAB at 4 and 7 °C. S. enterica SM 14028 and SM 129 could grow in semi-hard cheeses non-inoculated with LAB, while when LAB was inoculated, S. enterica was inactivated. The findings of this study indicated that the δ of L. monocytogenes strains was more affected in cheeses inoculated with LAB than the δ of S. enterica. • Selected lactic acid bacteria (LAB) impact the Listeria growth in Minas Cheese. • LAB caused inactivation of L. monocytogenes in semi-hard cheese. • Effects of LAB on S. enterica growth varied with cheese type and strain tested. • LAB influenced the ending pH for all treatments, regardless the cheese type. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate technological (acidification, proteolysis, lipolysis, resistance to low pH, NaCl, and bile salts) and biopreservation (antimicrobial activity against foodborne pathogens) features of 1002 LAB by high throughput screening (HTS) methods. The LAB was isolated from 11 types of Brazilian artisanal cheeses (BAC) marketed in the main 5 producing regions. Remarkable intra-species variability in acidification rates have been found, which was most pronounced between isolates from Mina's artisanal cheeses, Caipira and Coalho cheeses. Lacticaseibacillus paracasei and Levilactobacillus brevis showed the fastest acidification rate; however, all isolates showed slower acidification rates than a lactococcal control strain (4.3 × lower). When testing inhibitory effects, > 75% of LAB isolates could inhibit the growth of Staphylococcus aureus ATCC 19095 and Listeria monocytogenes ATCC 7644. Two of these isolates, identified as Lactiplantibacillus plantarum and Lentilactobacillus buchneri , the sterile and neutral supernatants alone, were sufficient to inhibit L. monocytogenes growth. Principal component analysis (PCA) allowed the identification of functional groups based on proteolytic and lipolytic activity, osmotic stress resistance, and inhibition of L. monocytogenes. The type of cheese the isolates were recovered from influenced properties such as anti-listerial compounds and lipolytic enzyme production. The use of HTS and multivariate statistics allowed insights into a diverse set of LAB technological and biopreservation properties. These findings allow a profound knowledge of the heterogeneity of a large set of isolates, which can be further used to design starter cultures with varied and combined properties, such as biopreservation and technological features. Besides that, HTS makes it possible to analyze a vast panel of LAB strains, reducing costs and time within laboratory analysis, while avoiding the loss of information once all LAB are tested at the same time (differently from the traditional labor-intensive approach, in which a few numbers of strains is tested per time). • Lactic acid bacteria (LAB) isolated from 11 types of Brazilian artisanal cheeses. • Biopreservation and technological features of LAB assessed by high-throughput tools. • Multivariate approach grouped LAB based on technological and preservation features. • Inhibitory activity and enzyme production of LAB seemed to be cheese-dependent. • Heterogeneity of large LAB set is key to design starter culture with chosen traits. [ABSTRACT FROM AUTHOR]

• Probiotic and biopreservation potential of 220 lactic acid bacteria. • Twenty-two out of 220 LAB satisfied in vitro criteria as probiotic candidates. • Technological and functional traits varied in LAB isolated from artisanal cheeses. • L. plantarum (1QB77) led up to 4 log reductions of S. aureus and L. monocytogenes in microcheeses. • Insights on indigenous LAB traits as starter cultures for tailored applications. The increasing interest in products with functional properties has encouraged the search for new lactic acid bacteria (LAB) present in natural sources, as traditional fermented foods. In this study, a large set of wild LAB isolates (n = 220) from Brazilian artisanal cheeses (BAC) were assessed for their probiotic and biopreservation potential. First, the rational selection was performed. From the tested isolates, 92 (41.8 %) were resistant to low pH (2 and 3). These isolates were submitted to bile salt (0.4 % Oxgall powder) resistance, and 22 were selected and submitted to adhesion assays. The autoaggregation values ranged from 68.5–99% and were considered moderate to high (20–70 %). Hydrophobicity values varied significantly between LAB (5.0–64.3%), and seven isolates presented values higher than 40 %. All selected LAB (n= 22) were capable of adhering to Caco-2 (> 70 %) cells, and none isolate displayed any tested gene for biogenic amine production. Most isolates (18/22) showed less than 1 log CFU reduction after passage through the simulated gastrointestinal tract (GIT) conditions. A total of twenty isolates satisfied key in vitro criteria to be considered as probiotics. A hierarchical cluster analysis (HCA) was performed, and two clusters were observed, showing high variability between Lactobacillus plantarum isolates regarding adhesion properties and survival to GIT stress and one influence of the source of isolation on these properties. After screening, the antimicrobial activity of Lb. plantarum (1QB77) was tested in microcheeses in which survival of two relevant pathogenic bacteria (Staphylococcus aureus and Listeria monocytogenes) was monitored along ripening and after a simulated GIT passage, concomitantly. L. plantarum (1QB77) has shown the ability to reach high counts (∼ 9 log CFU/g) at the end of ripening. This isolate was also able to reduce counts of S. aureus and L. monocytogenes in microcheeses in approx. 2.3 and 2.5 log CFU/g, respectively, until the 21st day of ripening; and about 3.2 and 3.5 log CFU/g after simulated GIT passage. Overall, the assessment of the probiotic properties of a large set of LAB was fundamental for gaining insights on the technological, functional, and potential regional traits of wild LAB isolates that can be used to develop starter cultures for tailored applications. [ABSTRACT FROM AUTHOR]

Traditionally fermented food generally has unique sensorial aspects due to its high microbial diversity, being broadly consumed worldwide. Despite this, some Vancomycin-Resistant-Enterococci (VRE) can occur in these products, which raises questions about their safety. Thus, this study tries to assess information about the occurrence of Enterococcus strains in traditional Brazilian cheese samples collected from the five main regions as well as the characterization of their phenotypic (proteolytic, lipolytic and bacteriogenic potential) and safety (hemolysin activity and growth at commercial VRE selecting media) aspects. A total of 1669 lactic acid bacteria were isolated, of which 605 (36.2%) were identified as Enterococcus by 16sRNA sequencing. Out of these, E. faecium (58.7%) was identified as the dominant species, followed by Enterococcus faecalis (31.8%), Enterococcus durans (4.8%), Enterococcus hermanniensis (1.6%) and Enterococcus gilvus (1.6%). All the data were analyzed by multivariate statistics, and the findings highlighted the presence of Enterococcus as a naturally component of indigenous microbiota of Brazilian artisanal cheeses, mostly in the cheeses of Marajó, Coalho, and Manteiga, possibly as a consequence of their heat resistance and the curd cooking step applied during the process in these regions. The majority of the identified Enterococcus (63.1%) did not produce β-hemolysin and were not resistant to vancomycin. Interestingly some of these strains (21.4%) were able to inhibit Listeria monocytogenes ATCC 35152, mostly isolates from Serrano, Colonial, and Minas artisanal (from Cerrado microregion) cheeses. Also, 10.2 and 11.8% of them have shown moderate to high proteolytic and lipolytic activity, respectively. Anti -listerial activity is of most interest as it can contribute to reduce risk of listeriosis due to dairy products consumption, while proteolysis and lipolysis are responsible for some remarkable features (e. g. flavor, taste, and texture) of fermented foods. In summary, this study represents a contribution towards revealing some phenotypic and safety traits of a large set of strains of Enterococcus strains through the use of multivariate statistics combined with high throughput tools. • Large sampling (n = 582) to assess Enterococcus in Brazilian artisanal cheese (BAC). • Total of 1669 lactic acid bacteria isolated and 605 (36.2%) were Enterococcus. • High throughput tools used to assess phenotypic and safety Enterococcus properties. • 63.1% of Enterococcus did not produce β-hemolysin and were sensible to vancomycin. • Multivariate statistics allowed the link between Enterococcus properties BAC types. [ABSTRACT FROM AUTHOR]

The fate of Listeria monocytogenes during ripening of artisanal Minas semi-hard cheese, as influenced by cheese intrinsic properties and by autochthonous (naturally present) or intentionally-added anti-listerial lactic acid bacteria (LAB) was modeled. Selected LAB strains with anti-listerial capacity were added or not to raw or pasteurized milk to prepare 4 cheese treatments. Counts of LAB and L. monocytogenes , pH, temperature and water activity were determined throughout cheese ripening (22 days, 22±1ᵒC). Different approaches were adopted to model the effect of LAB on L. monocytogenes : an independent approach using the Huang primary model to describe LAB growth and the linear decay model to describe pathogen inactivation; the Huang-Cardinal [pH] model using the effect of pH variation in a dynamic tertiary approach; and the Jameson-effect with N max tot model which simultaneously describes L. monocytogenes and LAB fate. L. monocytogenes inactivation occurred in both treatments with added LAB and inactivation was faster in raw milk cheese (−0.0260 h−1) vs. pasteurized milk cheese (−0.0182 h−1), as estimated by the linear decay model. Better goodness-of-fit was achieved for the cheeses without added LAB when the Huang primary model was used. A faster and great pH decline was detected for cheeses with added LAB, and the Huang-Cardinal [pH] model predicted higher pathogen growth rate in cheese produced with raw milk, but greater L. monocytogenes final concentration in pasteurized milk cheese. The Jameson-effect model with N max tot predicted that LAB suppressed pathogen growth in all treatments, except in the treatment with pasteurized milk and no LAB addition. The Huang-Cardinal [pH] model was more accurate in modeling L. monocytogenes kinetics as a function of pH changes than was the Jameson-effect model with N max tot as a function of LAB inhibitory effect based on the goodness-of-fit measures. The Jameson-effect model may however be a better competition model since it can more easily represent L. monocytogenes growth and death. This study presents crucial kinetic data on L. monocytogenes behavior in the presence of competing microbiota in Minas semi-hard cheese under dynamic conditions. • Three different approaches were evaluated to predict L. monocytogenes behavior in semi-hard cheese. • All proposed models were capable of closely describing L. monocytogenes growth/death potential. • Huang-Cardinal [pH] present better fit quality than the Jameson-effect model. • The Huang-Cardinal model was not able to describe inactivation. • Addition of anti-listerial LAB results in a decrease in L. monocytogenes. [ABSTRACT FROM AUTHOR]

In this work, the amplicon sequencing of the 16 S rRNA gene was employed to investigate the bacterial diversity in ingredients, processing environment, and ripened cheeses collected from three farms producing Serra da Canastra artisanal cheese. The data obtained indicated a remarkable variability in the bacteria consortia of the milk, whey, and environmental samples collected in farms 1, 2, and 3, despite their location in the same city. On the other hand, the starter culture and final product (ripened cheese) presented more constant and similar microbiota no matter the farm. The findings suggest that Streptococcus and Lactococcus have competitive advantages throughout Serra da Canastra cheese-making/ripening, which is crucial for their high relative abundance in the final products. An exploratory assessment based on sequencing data available in the literature showed that the Serra da Canastra cheeses sequences clustered with specific cheese varieties that are also made from raw milk but ripened for very different periods. The findings of this study highlight that despite the variability of milk and whey microbiota among the three farms, the starter culture ("pingo") has strong relevance in shaping the microbiota of the final product. Image 1 • Bacterial diversity through three Serra da Canastra cheese (SCC) farms revealed. • The microbiota was studied from milk to ripened cheese and the dairy environment. • Microbiota present in the milk used for SCC-making varied among the three farms. • Starter culture ("pingo") is key in shaping the microbiota of SCC. • Streptococcus and Lactococcus prevailed in SCC microbiota no matter the farm size. [ABSTRACT FROM AUTHOR]