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This systematic review and meta-analysis compile the in vitro antimicrobial efficacy of lactic acid bacteria (LAB) supernatants against three common pathogenic bacteria found in dairy products: Salmonella spp., L. monocytogenes, and Staphylococcus aureus. After screening and analysis of full papers, identified by searches in PubMed, Scopus, and Web of Science databases, thirty-nine studies were regarded as relevant, and a total of 510 observations were recorded. The effects of moderators on inhibition diameters were assessed by adjusting three pathogen-specific meta-regression models. Results showed that, in general terms, strains from the Enterococcus genus displayed the highest inhibition values against L. monocytogenes (15.90 ± 2.138 mm), whereas Lacticaseibacillus strains were more effective against S. aureus (11.89 ± 0.573 mm). The well diffusion test outperformed the spot and disk diffusion tests, and more acidic LAB supernatants resulted in higher measurements of inhibition diameters (p < 0.001). Meta-regression models incorporating LAB genus, pathogen concentration, and incubation time explained 33.8%, 52.3%, and 19.8% of the total variance in inhibition diameters for L. monocytogenes, Salmonella spp., and S. aureus, respectively. None of the three models showed evidence of publication bias. This meta-regression study demonstrated that LAB strains present in dairy products possess a variable capacity to inhibit any of the three foodborne pathogens. Overall, L. monocytogenes was found to exhibit greater susceptibility than Salmonella spp. and S. aureus; thus, the antilisterial capacity of the selected LAB strains could be exploited in developing biocontrol strategies for cheese-making. [ABSTRACT FROM AUTHOR]

A review of quantitative risk assessment (QRA) models of Listeria monocytogenes in produce was carried out, with the objective of appraising and contrasting the effectiveness of the control strategies placed along the food chains. Despite nine of the thirteen QRA models recovered being focused on fresh or RTE leafy greens, none of them represented important factors or sources of contamination in the primary production, such as the type of cultivation, water, fertilisers or irrigation method/practices. Cross-contamination at processing and during consumer's handling was modelled using transfer rates, which were shown to moderately drive the final risk of listeriosis, therefore highlighting the importance of accurately representing the transfer coefficient parameters. Many QRA models coincided in the fact that temperature fluctuations at retail or temperature abuse at home were key factors contributing to increasing the risk of listeriosis. In addition to a primary module that could help assess current on-farm practices and potential control measures, future QRA models for minimally processed produce should also contain a refined sanitisation module able to estimate the effectiveness of various sanitisers as a function of type, concentration and exposure time. Finally, L. monocytogenes growth in the products down the supply chain should be estimated by using realistic time–temperature trajectories, and validated microbial kinetic parameters, both of them currently available in the literature. [ABSTRACT FROM AUTHOR]

Invasive listeriosis, due to its severe nature in susceptible populations, has been the focus of many quantitative risk assessment (QRA) models aiming to provide a valuable guide in future risk management efforts. A review of the published QRA models of Listeria monocytogenes in seafood was performed, with the objective of appraising the effectiveness of the control strategies at different points along the food chain. It is worth noting, however, that the outcomes of a QRA model are context-specific, and influenced by the country and target population, the assumptions that are employed, and the model architecture itself. Studies containing QRA models were retrieved through a literature search using properly connected keywords on Scopus and PubMed®. All 13 QRA models that were recovered were of short scope, covering, at most, the period from the end of processing to consumption; the majority (85%) focused on smoked or gravad fish. Since the modelled pathways commenced with the packaged product, none of the QRA models addressed cross-contamination events. Many models agreed that keeping the product's temperature at 4.0–4.5 °C leads to greater reductions in the final risk of listeriosis than reducing the shelf life by one week and that the effectiveness of both measures can be surpassed by reducing the initial occurrence of L. monocytogenes in the product (at the end of processing). It is, therefore, necessary that future QRA models for RTE seafood contain a processing module that can provide insight into intervention strategies that can retard L. monocytogenes' growth, such as the use of bacteriocins, ad hoc starter cultures and/or organic acids, and other strategies seeking to reduce cross-contamination at the facilities, such as stringent controls for sanitation procedures. Since risk estimates were shown to be moderately driven by growth kinetic parameters, namely, the exponential growth rate, the minimum temperature for growth, and the maximum population density, further work is needed to reduce uncertainties. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) are a class of natural products that exhibit potent antimicrobial properties against a broad spectrum of bacteria. Inhibition diameters (IDs) and minimum inhibitory concentrations (MICs) are the typical measures of antimicrobial activity for extracts and EOs obtained from Cinnamomum, Salvia, and Mentha species. This study used a meta‐analytical regression analysis to investigate the correlation between ID and MIC measurements and the variability in antimicrobial susceptibility tests. By utilizing pooled ID models, this study revealed significant differences in foodborne pathogens' susceptibility to extracts, which were dependent on both the plant species and the methodology employed (p <.05). Cassia showed the highest efficacy against Salmonella spp., exhibiting a pooled ID of 26.24 mm, while cinnamon demonstrated the highest efficacy against Bacillus cereus, with a pooled ID of 23.35 mm. Mint extract showed the greatest efficacy against Escherichia coli and Staphylococcus aureus. Interestingly, cinnamon extract demonstrated the lowest effect against Shiga toxin‐producing E. coli, with a pooled ID of only 8.07 mm, whereas its EOs were the most effective against this bacterial strain. The study found that plant species influenced the MIC, while the methodology did not affect MIC measurements (p >.05). An inverse correlation between ID and MIC measurements was identified (p <.0001). These findings suggest that extracts and EOs obtained from Cinnamomum, Salvia, and Mentha spp. have the potential to inhibit bacterial growth. The study highlights the importance of considering various factors that may influence ID and MIC measurements when assessing the effectiveness of antimicrobial agents. [ABSTRACT FROM AUTHOR]

"Chouriço de carne" is a Portuguese ready-to-eat dry fermented sausage which relies on effective spontaneous fermentation to ensure its microbial safety and desired organoleptic properties. This study aimed to assess selected microbiological and physicochemical characteristics of artisanal chouriço produced by 14 different regional producers. Aerobic mesophilic bacteria, lactic acid bacteria, Staphylococcus aureus, Clostridium spp., Listeria spp. and Salmonella spp., in addition to pH, water activity and moisture, were evaluated for each of 70 samples. Principal Component Analysis of all these attributes was performed to build quality maps of the analyzed lots. The results showed great variability between sausages of different producers within the same geographic region, and S. aureus, Clostridium spp., Salmonella spp. and Listeria spp. were identified in sausages of several producers, highlighting the need for stricter microbiological control and standardization of production processes among artisanal producers of chouriço. [ABSTRACT FROM AUTHOR]

Artisanal fermented products constitute a worthwhile source of autochthonous lactic acid bacteria (LAB) with biopreservative, technological and organoleptic potential. This study aimed to characterize the fate of autochthonous LAB in artisanal goat's raw milk fresh cheeses at different temperatures by using an omnibus (one-step) modeling strategy. Lab-scale cheese prototypes (10 g) were artisanally elaborated from goat's raw milk and stored at 4, 12, 18 and 25 °C. LAB were enumerated (ISO:15214) during cheeses shelf-life. Growth models were fitted to the data, producing maximum growth rates averaging 0.345 ± 0.162 and 3.338 ± 0.907 ln CFU/g/d at 4 and 25 °C, respectively, and population increases averaged 3.388 ± 0.203 and 7.877 ± 1.480 ln CFU/g. The omnibus modeling approach allowed for the definition of a general model that describes autochthonous LAB growth with a correlation coefficient of 0.991 between experimental and estimated data. These results contribute to the better understanding of autochthonous LAB in artisanal cheeses for their further use as potential new-generation biopreservatives. [ABSTRACT FROM AUTHOR]

In the present study, the colour and C:N ratio of quinoa flours pigmented with M. purpureus supplemented with monosodium glutamate and sodium chloride were evaluated during 14 days of fermentation. The best values of L*, a* and b* corresponded to the eighth day. This research showed that the pigmented flour produced by solid state fermentation of quinoa by M. purpureus showing variations in the colour red along with the C:N ratio during the fermentation time, resulting in a product with good visual sensory attributes that can be used to develop new naturally pigmented products with potential functional characteristics. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) have a vast genetic potential and are used in food production. The aims of this work were to identify forty-six 16S ribosomal gene sequences of LAB isolated from goat's raw milk cheeses and to evaluate the phylogenetic relationship between the sequences. Using Sanger sequencing and the BLAST algorithm, the species were identified. Phylogenetic analysis was carried out using the R 4.3.0 software, and the genetic distance was calculated using the MEGA 11 software. The phylogenetic tree revealed variability between sequences of the same species, which may have implications for the technological capabilities of LAB sought for the production of cheeses of standardized quality. [ABSTRACT FROM AUTHOR]

Monascus purpureus is a red pigment-producing fungus. In the present study, the effect of fish hydrolysate and sodium chloride on the colour of quinoa flour fermented with M. purpureus was analysed. The colour of each sample was evaluated in CIELAB space (L*, a*, b*), in addition to the C:N ratio. The minimum fermentation time was eight days and the values of L* (44.66 ± 0.532), a* (20.27 ± 0.323), b*(17.89 ± 1.342) and a C:N ratio of 11.05 ± 0.240 were obtained. Therefore, there is an effect of supplementation on increasing the red colour of the meal. This work opened up the possibility that red quinoa flour could be used as a raw material in the production of other food products. [ABSTRACT FROM AUTHOR]

Mead is a traditional alcoholic beverage obtained by fermenting mead wort; however, its production still remains frequently an empirical exercise. Different meads can be produced, depending on fermentation conditions. Nevertheless, to date few studies have been developed on factors that may influence mead quality. The main objective of this work was to study the influence of sweetness and ethanol content on mead acceptability. Different meads were produced with two sweetness levels (sweet and dry meads) and three ethanol contents (18, 20, 22% (v/v)), adjusted by brandy addition. Afterwards, meads acceptability was evaluated by sensory analysis through a consumers’ panel (n=108) along with chemical analysis by HPLC-RID of glucose, fructose, ethanol, glycerol and acetic acid. The sweet (75 gglucose+fructose/L) and dry (23 gglucose+fructose/L) meads presented glycerol contents equal to 5.10±0.54 and 5.96±0.95 g/L, respectively, that were desirable since glycerol improves mead quality. Low concentrations of acetic acid were determined (0.46±0.08 and 0.57±0.09 g/L), avoiding the vinegar off-character. Concerning sensory analysis, the alcohol content of mead had no effect on the sensory attributes studied, namely, aroma, sweetness, flavour, alcohol feeling and general appreciation. Regarding sweetness, the “sweet meads” were the most appreciated by the consumers (score of 5.4±2.56), whereas the “dry meads” (score of 2.7±2.23) showed low acceptability. In conclusion, this work revealed that sweetness is a sensory key attribute for mead acceptance by the consumers, whereas ethanol content (18 to 22% (v/v)) is not.