The Use of Lactobacillus acidophilus and Bifidobacterium animalis ssp. Lactis BB12, as Probiotics to Reduce the Risk of Food Poisoning in Minced Meat

Background and Objective: For the first time, a detailed study of the antimicrobial metabolites produced by probiotics was carried out as an alternative natural way of chemical additives and to support consumer health. The study was undertaken using Lactobacillus acidophilus, Bifidobacterium animalis ssp. Lactis BB12, as well as and antimicrobial products as protective cultures to reduce the risk of food poisoning in minced meat.Materials and Methods: Samples of minced meat were stored at 4°C. The microbiological analysis of probiotics and pathogens bacteria was performed in days 0, 3, 7 and 14. In these periods, pH parameter and antimicrobial activity of the probiotics were analyzed.Results and Conclusion: During the cold storage, the counts of inoculated pathogens in the minced meat samples in co-culture with each specific probiotic decreased at different levels; some had significant decrease (p≤0.05) and some others showed no significant change (p>0.05). The probiotics displayed the ability to produce antibacterial substances (lactic acid, diacetyl and hydrogen peroxide) at different concentrations in the minced meat samples with significant increases (p≤0.05) until the end of cold storage. Probiotics exhibited the ability to produce bacteriocins. Lactobacillus acidophilus as a probiotic showed a significant effect as bio-preservative against pathogens and was more effective when combined with Bifidobacterium BB12

Characterization of Lactobacillus plantarum as a Potential Probiotic In vitro and Use of a Dairy Product (Yogurt) as Food Carrier

 Background and Objective: The current study was undertaken to check in vitro different characteristics of Lactobacillus plantarum as potential probiotic. These characteristics include viability of probiotic and pH during cold storage, tolerance to acid and bile, and antibiotic resistance.Material and Methods: Samples of yogurt were stored at 4°C and analyzed in time 0, 1, 3, 7, 10 and 14 days of storage. In these periods, probiotic and starter cultures were enumerated and the pH parameter was analyzed.Results and Conclusion: A gradual decline in pH was noticed throughout the storage. Counting of starter cultures decreased by 0.42 log cycle, and the probiotic's viability decreased by 0.68 log cycle at the end of storage, whereas the probiotic's viability inthe samples subjected to re-pasteurization decreased by 0.30, 0.22 log cycles in the selective and reference media, respectively. The average viable cell counts of Lactobacillus plantarum decreased by 0.76, and 0.28 log cycles after incubation period (3 h) at 37ºC in the simulated gastric juice (pH 2.0 and 3.0), respectively. Generally, probiotic can maintain its viability by 76.672% in (1.0% w v -1) bile. Lactobacillus plantarum was resistant to gentamicin, streptomycin, and vancomycin but susceptible to chloramphenicol, and tetracycline. Depended on these characteristics, Lactobacillus plantarum showed probiotic potential.Conflict of interest: The authors declare no conflict of interest

Localisation and Pre-calculation for Anti-missile Defence Shield System

One of the most important problems in anti-missile systems is localisation ambulatory missiles’ defence sites along with fixed missiles’ defence sites in best positions to destroy enemy’s missiles. For localisation, there are lots of constraints and consumptions, which should be considered to making predictions in missiles behaviours. An optimum algorithm for localisation of the missiles’ defence sites is provided. Predictions of attackers’ missiles behaviors for assisting real-time defending operations in the defender sites is also provided. One simulator for finding the best places to locate ambulatory missiles’ defence sites presented. This simulator considers fixed and ambulatory missiles’ defence sites along with their parameters to provide best solutions by relying on modified genetic algorithm.

Germination and Fermentation of Soybeans: Two Healthy Steps to Release Angiotensin Converting Enzyme Inhibitory Activity Compounds

Background and objective: Soybean is one of the most important grains with high proteins, good quality edible oils, appreciable amount of minerals and vitamins. Due to some disadvantages soybeans’ compounds affecting the flavor, odor and stability, different types and levels of processing are considered to make better products with healthy properties. Hypertension (high blood pressure) is one of the modern world diseases, which increases the risk of serious human health problems. There are several systems in humans’ body e.g. angiotensin converting enzyme regulator to blood pressure control. The aim of the present review is to report the effect of germination and fermentation on the concentration of bioactive compounds with angiotensin converting enzyme inhibitory properties. Results and conclusion: Many scientific research has demonstrated that germination (sprouting, also known as malting) and fermentation are two effective and inexpensive technologies improving soybean quality. During these two processes, anti-nutritional and bioactive compounds affecting human health e.g. anti-hypertension components have been removed and released, respectively. Furthermore, studies have shown effect of soybean isolated compounds to inhibit angiotensin converting enzyme. Therefore, soybean germination and fermentation could affect the concentration of bioactive compounds with angiotensin converting enzyme inhibitory properties. Conflict of interest:The authors declare no conflict of interest. &nbsp

Physicochemical Properties and Sensory Evaluation of Reduced Fat Fermented Functional Beef Sausage

Background and Objective: Semi-dry fermented sausages were manufactured from beef meat in three types: without starter culture (control), inoculated with Lactobacillus casei and inoculated with Lactobacillus paracasei. Probiotic fermented sausages are safe and healthy meat products, which receive high commercial interest and growing market shares.Material and Methods: The physico–chemical characteristics (Protein, Moisture, Fat, Ash, Lactic acid value and pH), microbiological features (total aerobic, total mold and yeast andlactic acid bacteria count) and sensory evaluation (color, flavor, texture and overall acceptability) were analyzed after 0, 10, 20, 30, 40 and 45 days of refrigerated storage at 4°C.Results and Conclusion: There was a significant difference (p≤0.05) in moisture content, which decreased in all samples during the period of refrigerated storage. However, all other parameters such as protein, fat and ash increased. The lactic acid produced during the fermentation by lactic acid bacteria resulted in a decrease in the pH value of all samples, and improved sensory evaluation of the fermented sausage inoculated with Lactobacillus casei and Lactobacillus paracasei during the storage period. The best results were obtained in the fermented sausage inoculated with Lactobacillus paracasei in physico-chemical, microbial and sensory characteristics. Also we could preserve the product at 4°C for 45 days.Conflict of interest: The authors declare that there is no conflict of interest

The effect of Saccharomyces strain and fermentation conditions on quality prameters of non-alcoholic beer

In this study, the effect of several species of fermenting yeast and fermentation conditions (periodic aeration and temperature) on quality parameters of non-alcoholic beer is assessed. Yeast starters with different inoculation percent were added separately into wort with determined gravity. Wort was fermented for 48 h in different temperatures under aerobic condition or periodic aeration (every 12 h). Growth rate, wort gravity and ethanol content were analyzed for 48 hours (12-h interval). Also, 6 trained panelists were asked for sensory evaluation of final product. The highest growth rate and the highest ethanol content were found in treatments with 4×107 cfu/ml inoculation fermented at 24˚C under periodic aeration and in those fermented under anaerobic conditions, respectively. The highest gravity was observed for treatments with 107 cfu/ml inoculation, periodic aeration and fermentation at 4˚C. The lowest growth rate and ethanol content were observed in treatments with 107 cfu/ml, fermented at 4˚C under anaerobic condition and those fermented under periodic aeration, respectively. In treatments with 4×107 cfu/ml inoculation, anaerobic condition and fermentation at 4˚C, the lowest gravity was observed. In addition, among yeasts, Saccharomyces cerevisiae and Saccharomyces rouxii showed the highest and the lowest growth rate, ethanol content and wort gravity, respectively. Additionally, treatments containing Saccharomyces cerevisiae resulted in non-alcoholic beer with more satisfactory flavor attributes

Valorization of Date By-Products: Enhancement of Antioxidant and Antimicrobial Potentials through Fermentation

The by-products from three varieties of dates—Mozafati, Sayer, and Kabkab—were subjected to solid-state fermentation using Aspergillus niger alone or in co-culture with Lactiplantibacillus plantarum or Limosilactobacillus reuteri to enhance their phenolic and flavonoid content, along with antioxidant and antimicrobial activities. Solid-state fermentation, being environmentally friendly and cost-effective, is particularly suitable for agricultural residues. Significant increases (p < 0.05) in total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant power were observed post-fermentation, especially under co-culture conditions. The highest TPC (12.98 ± 0.29 mg GA/g) and TFC (1.83 ± 0.07 mg QE/g) were recorded in the co-culture fermentation of by-products from the Mozafati and Sayer varieties, respectively. HPLC analysis revealed changes in polyphenol profiles post-fermentation, with reductions in gallic and ferulic acids and increases in caffeic acid, p-coumaric acid, rutin, quercetin, and kaempferol. FT-IR analysis confirmed significant alterations in polyphenolic functional groups. Enhanced antimicrobial activity was also observed, with inhibition zones ranging from 8.26 ± 0.06 mm for Kabkab to 17.73 ± 0.09 mm for Mozafati. These results suggest that co-culture solid-state fermentation is a promising strategy for valorizing date by-products, with potential applications in nutraceuticals and/or pharmaceutical products and as valuable additives in the food industry

Investigation of the efficiency of various reactive mufflers by noise reduction and transmission loss analyses

Transmission loss and noise reduction of reactive mufflers are determined by linear acoustic theory and unsteady flow field study, respectively. The effects of extending the inlet tube of the muffler, adding holes to the extension, and the number of holes on both transmission loss and noise reduction are investigated. In noise reduction analysis, the Navier-Stokes equations and k-ε model are used to study the unsteady turbulent flow. Helmholtz equation is solved for transmission loss analysis. The present study is validated with experimental data. Numerical results show a rise in noise reduction by extending the inlet tube of the muffler and increasing its length. Moreover, the extended mufflers cause more transmission loss and broadband behavior at some frequencies due to the resonances. According to the results, different points of view in the investigation of acoustic attenuation performance of mufflers can be helpful to understand more and better about the effect of geometrical parameters

Tuning the physicochemical, structural, and antimicrobial attributes of whey-based poly (L-Lactic Acid) (PLLA) films by Chitosan Nanoparticles

Recently, the research and innovation to produce raw materials from microbial processes has gained much attention due to their economic and environmental impacts. Lactic acid is a very important microbial product due to its wide application in the food, pharmaceutical, cosmetic, and chemical industries. In the current study, poly (L-lactic acid) (PLLA) was produced by the ring opening polymerization (ROP) technique of L-lactic acid recovered from whey fermentation, and was used for the production of nanocomposites films reinforced with chitosan nanoparticles (CNPs) (average diameter ca. 100–200 nm). Three different CNPs concentrations, namely 1, 3, and 5% w/w, were tested, and their influence on the physical, mechanical, thermal, antibacterial and structural attributes of PLLA film was assessed. The results showed that the addition of CNPs up to 3% caused a significant improvement in water vapor permeability, appearance, tensile strength and elongation at break. The antibacterial properties of nanocomposites followed a dose-depended pattern as a result of CNPs addition. Therefore, the best inhibitory effects on Escherichia coli and Staphylococcus aureus was made by the addition of 5% of CNPs and lower dosages slightly affected the growth of pathogens or didn\u27t cause any inhibitory effects (in 1% of CNPs). It can be concluded that the incorporation of CNPs into the PLLA matrix allows to improve the structural, thermal, physical, mechanical and antibacterial properties of the polymer, generating promising systems for food packaging and biomedical applications

Effect of refrigerated storage on the probiotic survival and sensory properties of milk/carrot juice mix drink

Background: There is a genuine interest in the development of probiotic milk and juice based beverages because they are a good-vehicle to deliver probiotic microorganisms to consumers. For this purpose, the viability and metabolism of four probiotic strains ( Lactobacillus acidophilus LA5, Bifidobacterium lactis BB12, L. rhamnosus and L. plantarum ) were studied in non-fermented milk and carrot juice mix drink. The drinks were evaluated in 5 days interval for viable cell count, pH, acidity, sedimentation and sensory quality during refrigerated storage at 4 \ub1 2\ubaC for up to 20 days. Results: The results showed that all strains had good viability in milk/carrot juice drink (88-98%), but L. acidophilus LA5 seemed more stable than three other strains. The levels of pH and acidity were ranged 5.33-6.6 and 0.13-0.31%, respectively. The drinks inoculated with L. rhamnosus and control (non-probiotic) showed more variation in pH and acidity. The most sedimentation was detected in drinks inoculated with L. rhamnosus, reaching 3.73 mL/10 mL sample. Sensory assessment indicated lowest acceptability in control and milk/carrot juice drink inoculated with L. rhamnosus, respectively. Conclusion: This study indicated that some probiotic bacteria can be applied by food producers to produce functional drinks with an increased shelf-life