A new innovative method, MICA Legionella, allows for the automatic enumeration of Legionella pneumophila in domestic water samples in 2 days, with a detection limit of 2 CFU per test portion. Here we show that it gives equivalent results to those obtained by the French standard method NF T90-431 in 7 to 15 days.

Listeria monocytogenes, one of the main foodborne pathogens, is commonly found in milk and dairy products. This study aimed to estimate the presence of L. monocytogenes in milk and dairy product supply chains using a meta-analysis based on PubMed, Embase, Web of Science, and Scopus databases. A total of 173 studies were included in this meta-analysis. The pooled prevalence in the supply chain environment was 8.69% (95% confidence interval [CI]: 5.30%-12.78%), which was higher than that in dairy products (4.60%, 95% CI: 1.72%-8.60%) and milk products (2.93%, 95% CI: 2.14%-3.82%). Subgroup analysis showed that L. monocytogenes prevalence in raw milk (3.44%, 95% CI: 2.61%-4.28%) was significantly higher than in pasteurized milk (0.60%, 95% CI: 0.00%-2.06%). The highest prevalence of L. monocytogenes in milk and dairy products was observed in North America (5.27%, 95% CI: 2.19%-8.35%) and South America (13.54%, 95% CI: 3.71%-23.37%). In addition, studies using culture and molecular methods (5.17%, 95% CI: 2.29%-8.06%) had higher prevalence than other detection methods. Serogroup 1/2a and 3a (45.34%, 95% CI: 28.74%-62.37%), serogroup 1/2b and 3b (14.23%, 95% CI: 6.05%-24.24%), and serogroup 4b/4e (13.71%, 95% CI: 6.18%-22.83%) were dominant in these studies. The results of this study provide a better understanding of the prevalence of L. monocytogenes in milk and dairy product supply chains and suggest a potential foodborne pathogen burden.

This innovative study introduces the application of a 5% (v/v) poppy seed phenolic extract-infused edible chitosan coating on fresh-cut fruit salads (comprising apple, pineapple, pomegranate, and kiwi) stored at +4°C for 12 days. Non-coated samples experienced notable changes: 4.30% weight loss, 25% decay, pH level at 3.59, titratable acidity of 0.18%, and browning index of 1.71. In contrast, fruit salads coated with chitosan-poppy seed phenolic extract exhibited significant improvements: weight loss reduced to 3.10%, decay limited to 3.13%, pH increased to 3.76, titratable acidity enhanced to 0.20%, and browning index notably decreased to 0.33. Soluble solids ranged from 11.83 to 14.71, L* from -8.13 to 18.64, a* from -1.85 to 22.35, and b* from 8.26 to 27.89 in non-coated salads. Adding poppy seed phenolic extract to the coated fruits slightly expanded these ranges. Sensory evaluations consistently rated non-coated samples between 1 and 3, while the coated samples received higher ratings between 6 and 7. These assessments consistently highlighted enhanced attributes, including intensified aroma, enriched color, improved taste, texture, and overall acceptability. Moreover, incorporating poppy seed phenolic extract amplified sensory qualities and significantly improved microbial safety (<106 CFU/g). In summary, the chitosan-based coating, enriched with poppy seed phenolic extract, effectively extended the shelf life of fresh-cut fruit salads. This integrated approach preserves key attributes, ensures microbial quality, and enhances the sensory characteristics of these products. The study\'s results emphasize its potential as a pivotal innovation in food preservation by providing specific and tangible outcomes.

In this study, fresh-cut fruit salads composed of apples, pears, kiwis, and pineapples were stored at +4 °C for 18 days under distinct conditions: non-coated (NC), chitosan-coated (CH), and bergamot juice powder extract-enriched chitosan-coated (CHBE). Storage endpoint decay percentages were as follows: NC group: 100%, CH group: 26.67-53.3%, CHBE group: 13.33-26.67%. CHBE had the highest moisture content (87.05-89.64%), soluble solids (12.40-13.26%), and chroma values (2.35-6.60). CHBE and NC groups had 2.10% and 6.61% weight loss, respectively. The NC group had the highest polyphenol oxidase activity (19.48 U mL-1) and browning index (0.70 A420/g); CH group: 0.85 U mL-1, 0.35 A420/g; CHBE group: 0.57 U mL-1, 0.27 A420/g. CHBE showed a titratable acidity of 1.33% and pH 3.73 post-storage, impeding microbial proliferation with the lowest counts (2.30-3.24 log CFU g-1). The microbial suitability of the NC group diminished after day 6, with an overall preference score of 1.00. Conversely, the CH and CHBE groups scored 3.15 and 4.56, highlighting the coatings\' effectiveness. Bergamot juice powder extract further enhanced this, mitigating browning and enhancing quality. Results reveal tailored coatings\' potential to extend shelf life, improve quality, and enhance fruit salads\' acceptability. This study underscores the importance of edible coatings in addressing preservation challenges, emphasizing their role in enhancing food quality and consumer acceptability. Incorporating edible coatings is pivotal in mitigating deterioration issues and ensuring the overall success of fresh-cut fruit products in the market.

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In present study, sodium alginate biodegradable films containing different concentrations of resveratrol (RES: 0.002% and 0.004%) or thymol (THY: 0.5% and 1%) and their combinations were prepared, and evaluated for their effects on spoilage-related microbial profile, lipid oxidation, sensory properties, and protective effects against Listeria monocytogenes in beef mortadella sausage during 40 days storage at 4°C. The release rate of phenolic compounds was determined by the Folin-Ciocalteu test. To assess the shelf life of the product, changes in total viable count (TVC), lactic acid bacteria count (LAB), psychrotrophic bacteria count (PTC), pH levels, thiobarbituric acid reactive substances (TBARS) levels, and sensory characteristics (taste, color, odor, and overall acceptability) were evaluated. For the sensory evaluation, a panel of 70 semi-trained judges was selected according to their initial performance. Samples wrapped with sodium alginate films containing 1% THY (alone or combined with different concentrations of RES) exhibited lower bacterial counts compared to other experimental groups at the end of the storage period (6.01-6.35 vs. 6.71-8.17 log10 CFU/g for TVC, 5.37-5.83 vs. 6.07-7.11 log10 CFU/g for LAB, 5.08-5.18 vs. 5.40-7.23 log10 CFU/g for PTC, and 6.53-6.92 vs. 7.23-9.01 log10 CFU/g for inoculated L. monocytogenes). Sodium alginate films containing the combination of 0.004% RES and different concentrations of THY showed higher antioxidant effects than other experimental groups (TBARS values of 1.68-1.99 vs. 2.23-3.80 mg MDA/kg sample). The sodium alginate film containing 0.004% RES + 1% THY exhibited the highest antimicrobial and antioxidant activities and highest sensory scores among all treatments. These findings highlight the potential application of the sodium alginate film containing a combination of RES and THY as an active packaging material with natural preservatives in the meat products industry. This application can effectively extend the shelf life and enhance the microbial safety of clean-label cooked sausages during refrigerated storage.

During commercial production of liquid egg yolk (LEY), phospholipase A2 (PLA2) is used to improve its emulsification capacity and thermal stability. The enzymatic treatment may occur at elevated temperatures such as 50 °C, potentially allowing foodborne pathogens, such as Bacillus cereus, to grow. Little knowledge is available concerning growth of B. cereus in LEY during PLA2 treatment. Therefore, the objective of this study was to investigate the growth kinetics of B. cereus during PLA2 treatment using pathogenic B. cytotoxicus NVH391-98, the most thermotolerant member in the B. cereus group, as a surrogate. Inoculated LEY samples were placed in precision programmable incubators to observe the growth of B. cytotoxicus NVH391-98 under multiple isothermal and dynamic temperature conditions between 20 and 53 °C. The bacterial growth was described using the differential Baranyi model coupled with two different secondary models. The kinetic parameters were determined using one-step dynamic inverse analysis of multiple growth curves. The least square method was used in combination with the 4th order Runge-Kutta method to solve the differential Baranyi model using multiple growth curves to determine the cardinal kinetic parameters. The results showed that B. cytotoxicus NVH391-98 can grow prolifically at 50 °C. The estimated minimum, optimum and maximum temperatures were 16.7 or 18.5, 47.8 or 48.1, and 52.1 or 52.4 °C, respectively, depending on the secondary models, with an optimum growth rate of 2.1 log colony-forming-unit (CFU)/g per hour. The dynamic model is validated using isothermal curves with reasonable accuracy. B. cytotoxicus died off slowly at 15 °C. At 55 °C, thermal inactivation was observed, with a D value of approximately 2.7 h. Holding at 55 °C or below 15 °C can effectively prevent the growth of B. cytotoxicus in egg yolk.

Hepatitis A virus (HAV) has adversely affected public health worldwide, causing an economic burden on many countries. Fresh vegetables are reported as a source of HAV infections during production, harvesting, and distribution, which cause the emergence of foodborne illnesses. Therefore, in this study, the synergistic effects of chemical (sodium hypochlorite [NaOCl] and chlorine dioxide [ClO2]) and physical (electron-beam [e-beam] irradiation) sequential treatment for HAV inactivation on fresh vegetables were investigated, and the physicochemical quality changes of vegetables were evaluated after each treatment. On bell pepper and cucumber sequentially treated with NaOCl (50-500 ppm) and e-beam (1-5 kGy), the HAV titer was reduced by 0.19-4.69 and 0.28-4.78 log10 TCID50/mL, respectively. Sequential treatment with ClO2 (10-250 ppm) and e-beam (1-5 kGy) reduced the HAV titer on bell pepper and cucumber by 0.41-4.78 and 0.26-4.80 log10 TCID50/mL, respectively. The sequential treatments steadily decreased the HAV titers on each food by a significant difference (p < 0.05) compared to the controls. The treatment combinations of 500 ppm NaOCl and 3 kGy (e-beam) on bell pepper and 150 ppm NaOCl and 1 kGy (e-beam) on cucumber provided maximum synergistic effects. It was also found that sequential treatment with 50 ppm ClO2 and 5 kGy (e-beam) on bell pepper and 10 ppm ClO2 and 5 kGy (e-beam) on cucumber most efficiently inactivated HAV. Additionally, bell pepper and cucumber showed no significant quality changes (p < 0.05) after the treatment. Therefore, the sequential treatment with NaOCl or ClO2 and e-beam is expected to effectively control HAV on fresh vegetables without changing the food quality compared to either treatment alone.

OBJECTIVE: Sous-vide cooking offers several advantages for poultry meat, including enhanced tenderness, reduced cooking loss, and improved product yield. However, in duck meat, there are challenges associated with using the sous-vide method. The prolonged cooking time at low temperatures can lead to unstable microbial and oxidative stabilities. Thus, we aimed to assess how varying sous-vide cooking temperatures and durations affect the physicochemical and microbial characteristics of duck breast meat, with the goal of identifying an optimal cooking condition.
METHODS: Duck breast meat (Anas platyrhynchos) aged 42 days and with an average weight of 1,400±50 g, underwent cooking under various conditions (ranging from 50°C to 80°C) for either 60 or 180 min. Then, physicochemical, microbial, and microstructural properties of the cooked duck breast meat were assessed.
RESULTS: Different cooking conditions affected the quality attributes of the meat. The cooking loss, lightness, yellowness, Hue angle, whiteness, and thiobarbituric acid reactive substance (TBARS) values of the duck breast meat increased with the increase in cooking temperature and time. In contrast, the redness and chroma values decreased with the increase in cooking temperature and time. Cooking of samples higher than 60°C increased the volatile basic nitrogen contents and TBARS. Microbial analysis revealed the presence of Escherichia coli and Coliform only in the samples cooked at 50°C and raw meat. Cooking at lower temperature and shorter time increased the tenderness of the meat. Microstructure analysis showed that the contraction of myofibrils and meat density increased upon increasing the cooking temperature and time.
CONCLUSIONS: Our data indicate that the optimal sous-vide method for duck breast meat was cooking at 60°C for 60 min. This temperature and time conditions showed good texture properties and microbial stability, and low level of TBARS of the duck breast meat.

Disinfection is essential in water and wastewater treatment process as a guarantee for microbial safety. This study systematically investigated: (i) the inactivation characteristics of bacteria widely existed in water, including Gram-negative bacteria (Escherichiacoli) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis spores), by sequential UV and chlorine disinfection processes (UV-Cl and Cl-UV), simultaneous UV and chlorine disinfection process (UV/Cl); and (ii) the disinfection mechanisms on different bacteria. The combination of UV and chlorine disinfection could inactive bacteria at lower doses, but showed no synergistic effect on E. coli. Contrarily, disinfection results indicated that UV/Cl performed an obvious synergistic effect on highly disinfectant-resistant bacteria (e.g. S. aureus and B. subtilis spores). Specifically, UV/Cl at the UV dose of 9 mJ/cm2 and chlorine dose of 2 mg-Cl/L could inactivate S. aureus completely. Moreover, the effectiveness of UV/Cl on the removal of indigenous bacteria in actual water conditions was also confirmed. In short, the study provides significant theoretical and practical implications for ensuring microbial safety during water treatment and use.