ali fazlara

Phenolic compounds with antioxidant and antiradical properties have important role in food preservation and human health. Phenolic compounds are important compounds ofdate palm seeds usually show high antioxidant activity. In this study, the effect of phenolic compounds extracted from date palm seeds on probiotic bacteria is studied, the total amount of ethanol extract date palm seeds, using the Folin-Ciocateu reagent and the antioxidant activity of the extract using the DPPH reagent was evaluated against BHT. Prebiotic effect of phenolic compounds of date palm seeds on growth and survival of probiotic bacteria Lactobacillus plantarum, (ATCC14917) in three concentrations 0.1, 0.5, 1 % compared with green tea extract and extract antimicrobial effect against Staphylococcus aureus and E.coli were performed at 0.5, 1 %.The total dry extract ethanol date palm seeds phenolic compounds was found 6.62 % on galic acid. Free radical scaverning rate 48.27 %, IC50for ethanol palm seeds183.73 μg/mL was calculated. According to the HPLC output, which confirm high amounts of Gallic acid and Catechin as phenolic compounds in from date palm seed. The results showed that phenolic compounds extracted from date palm seeds has increased the viability of probiotic bacteria in the level 0.5, 1% and some what have antibacterial effect on the concentration of 1% on bactria Staphylococcus aureus. Acording to the results, phenolic compounds extracted from date palm seeds showed good prebiotic functionality.

Although chemical antifungal preservatives are often used in various food products, the use of these substances has been limited due to their harmful effects on human health and the environment. Researchers have recently sought to replace these chemical compounds with natural and less dangerous substances. In this regard, using essential oils of medicinal plants can be considered a suitable alternative due to fewer side effects. Therefore, in the present research, after preparing the Badrashboo plant from the fields of Golmarz village located near Urmia city and drying it, extracting the essential oil from the Badrashboo was carried out using a Clevengerger, and the antifungal effect of Badrashboo essential oil on some important fungal strains with disc diffusion agar and well diffusion agar, minimum inhibitory concentration, minimum fungicidal concentration and the interaction of Badrashboo essential oil with Nystatin were performed. The results of disk diffusion agar and well diffusion agar tests showed that Badrashbo essential oil had a significant antifungal effect on all studied fungal strains. The results of the minimum inhibitory concentration of essential oil for strains of Saccharomyces cerevisiae, Candida albicans, Aspergillus niger, Fusarium solani, and Penicillium expansum were 8, 16, 2, 8, and 4 mg/ml, respectively. The minimum fungicidal concentration for the mentioned strains was 32, 64, 8, 16, and 32 mg/ml respectively. Also, the results of the interaction of Badrashboo essential oil with Nystatin indicated the synergistic effect of Badrashboo essential oil with Nystatin. Considering the significant antifungal effect observed for Badrashbo essential oil in the present study, it can be used in the food and pharmaceutical industries.

Nowadays, due to the harmful effects of chemical preservatives in food products and antibiotic resistance too, the efforts of researchers to use natural and safe antimicrobial compounds, including plant essential oils, have increased. In the present study, after collecting the Badrashboo plant from the fields around Urmia city and drying it, extracting the essential oil from the plant was carried out using a Clevenger device, and the antimicrobial effects of this essential oil against some Gram-positive and Gram-negative food-borne pathogenic bacteria were determined by methods Disk Diffusion Agar (DDA), Well Diffusion Agar (WDA), Minimum inhibitory concentration (MIC), Minimum bactericidal concentration (MBC) and interaction with four common broad-spectrum antibiotics including Vancomycin, Erythromycin, Chloramphenicol and Gentamicin were performed. The results of the DDA and WDA tests showed that the essential oil of Badreshbo had significant antimicrobial effects on all the tested bacteria in this study. The gram-positive bacteria were more sensitive than the gram-negative bacteria in front of this essential oil. The results of the MIC test of the essential oil for Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, Shigella dysentery, Staphylococcus aureus, Bacillus cereus, and Listeria monostogenes were 2.5, 1.25, 1.25, 0.625, 0.312, 1.25 and 1.25 mg/ml. The MBC of the mentioned strains were 5, 5, 2.5, 5, 2.5, 2.5, and 2.5 mg/mL, respectively. Also, the results of the study of the interaction effect of Badreshbo essential oil with the mentioned antibiotics indicate synergistic effects of the essential oil with all four antibiotics tested. Therefore, considering the significant antimicrobial effects observed for Badrashbo essential oil in this study, it can be used in the food and pharmaceutical industries.

Escherichia coli O157:H7 is a significant foodborne pathogen responsible for gastroenteritis, with low infectious doses, and as an enterohemorrhagic strain, it can cause hemorrhagic dysentery. Raw milk, including sheep milk, is a known source of contamination with this pathogen, posing a potential risk for severe human infections. This study aimed to evaluate the potential of raw sheep milk as a vector for the transmission of E. coli O157:H7 and its associated health risks. A total of 114 raw sheep milk samples were collected in Khuzestan province over four months (April–July 2022). After biochemical assays, the isolates were identified by using specific primers targeting the O157 (rfb), H7 (flic), stx1, and stx2 genes for identification. The study confirmed the isolation of E. coli O157:H7 from 3 samples (2.63%). Antibiogram was then conducted on the confirmed isolates. The results revealed that all isolates were 100% susceptible to imipenem, ceftazidime, and ceftazidime-clavulanic acid. Sixty-six percent of the isolates were susceptible to ciprofloxacin, gentamicin, trimethoprim-sulfamethoxazole, while 33% showed susceptibility to nalidixic acid and nitrofurantoin. None of the isolates were susceptible to ampicillin or clindamycin, indicating significant resistance to these antibiotics. The contamination of raw sheep milk with E. coli O157:H7 in the Khuzestan region suggests that consuming raw sheep milk may be associated with an increased risk of infections caused by this pathogen.

Chicken meat is considered as a valuable and inexpensive food item in human nutrition. This meat is a rich source of protein, essential amino acids and essential fatty acids. Nowadays, edible coatings with herbal essential oils are very effective in increasing the shelf life of food. One kind of packaging methods is the use of modified atmosphere. In this type of packaging, a specific gas composition (carbon dioxide, nitrogen and oxygen) replaces the air in the packaging and increases shelf life.The aim of this study was to investigate the possibility of using gelatin and peppermint essential oil as a natural coating to increase the shelf life of fresh chicken fillet in modified atmosphere packaging. Gelatin solution (4%) and gelatin solution (4%) containing (2%) (Mentha spicata) essential oil were prepared. Chicken fillet samples were divided into three groups without coating (control), coated with gelatin and coated with gelatin and Mentha spicata essential oil. After immersing the chicken samples for 5 minutes, take them out of the respective containers and after dripping excess secretions and drying, they were packed in special plastic bags for packaging in modified atmosphere conditions (5% O2, 60% N2 and 35% CO2) and kept in a refrigerator (temperature 4°C) for 21 days and on certain days (0, 3, 6, 9, 12, 15, 18 and 21) for microbiological tests (total count of aerobic mesophilic and psychrophilic bacteria), chemical (pH, values of volatile nitrogen substances (TVN)) and thiobarbituric acid (TBA) and sensory (appearance, elasticity, odor and color) were evaluated. Examining the bacterial results showed that the treatment of gelatin and especially the treatment of gelatin containing Mentha spicata essential oil had a significant effect on postponing the increase in psychrophilic and mesophilic microbial load compared to the control group. Also, the mentioned treatments had a significant effect in reducing the pH values, but statistically, no significant difference was seen between the treatments (P>0.05). In terms of sensory factors, control treatment and gelatin treatment maintained sensory factors at an acceptable level for six days and gelatin treatment containing Mentha spicata essential oil for nine days. Based on the obtained results, it can be stated that edible gelatin coating containing Mentha spicata essential oil, unlike only gelatin coating, can somewhat reduce the speed of the spoilage process and lead to an increase in the storage time of chicken fillets and their usability. Also, packaging in modified atmospheric conditions has played an important role in reducing the amount of chemical and microbial factors and has increased the shelf life of chicken fillet.

Sesame oil (SO) is one of the edible oils beneficial to health. The use of SO due to its high content of antioxidants and unsaturated fatty acids has many applications in the production of functional foods and pharmaceuticals. In recent years, many efforts have been made to use nanotechnology, including encapsulation technology, to protect functional foods from destructive environmental factors and thereby extend the shelf life of foods.

This study aimed to prepare and investigate the Physicochemical characteristics of SO-nanoemulsion coated with maltodextrin/acacia gum powder by spray drying method.

Sesame Oil-nanoemulsion (SO-NE) was prepared and encapsulated using maltodextrin and acacia gum. The coated nanoemulsion was spray dried, and its Physicochemical properties including Encapsulation Efficiency, Particle Size, Thermal Analysis, and zeta potential were investigated. The size and morphology of produced nanoparticles were investigated by FESEM imaging.

The mean particle size determined by the DLS technique and FESEM was 166.5 and 96.5 nm, respectively, with a spherical shape. The zeta potential of the coated SO-nanoemulsion was -48.1 mV, showing suitable stability. Comparison of thermograms of the coated nanoemulsion containing SO and without it did not show any change in the thermal behavior of the ingredients. According to the GC-MS analysis, the encapsulation efficiency was found to be 92.93 ± 4.61%.

It can be concluded that due to the high efficiency of encapsulation processes and spray drying technique in maintaining the Physicochemical Stability of SO, the method used in this research can be applied in the food and pharmaceutical industry.

Grape seed oil is a rich source of omega-9 and omega-6 fatty acids, but the problems related to the production of food enriched with omega-9 and omega-6 fatty acids (the predominant essential fatty acids in grape seed oil) It is accompanied by the spontaneous oxidation of long chain fatty acids, which leads to a shorter shelf life, and due to their hydrophobic and unstable properties, they are difficult to dissolve in water and are easily oxidized, which leads to destruction and emergence The flavor becomes unpleasant. Therefore, it is necessary to develop effective delivery systems that can use grape seed oil in liquid foods more effectively. Recently, the preparation of emulsions using the layer-by-layer (LBL) method has received a lot of attention due to its various advantages, including the complete encapsulation of lipids, preventing the attack of peroxides and controlling the release of bioactive compounds. To prepare multilayer emulsion, grape seed oil was added to 1% gelatin solution and homogenized with a homogenizer. For the secondary emulsion, the primary emulsion was mixed with 2% chitosan solution and homogenized with a homogenizer after adjusting the pH. To prepare a three-layer emulsion, basil seed gum solution was added to the double-layer emulsion and homogenized again. Then, the particle size, viscosity, zeta potential, turbidity and refractive index, peroxide and thiobarbituric acid index of the samples were checked during one month of storage at two temperatures of 4 and 25 . The results showed that the maximum stability of single-layer, double-layer and three-layer emulsions was at pH 5, and the stability increased with the increase in the number of layers of grape seed oil multilayer emulsion. In fact, at this pH, gelatin, chitosan, and basil seed gum have negative, positive, and negative charges, respectively, and strong electrostatic interactions occur between biopolymers, after which LBL emulsions become stable. After the one-month storage period of emulsions, the particle size, viscosity, turbidity, refractive index, peroxide and thiobarbituric acid value have increased. Also, during the one-month storage period, by examining the physicochemical parameters (particle size, viscosity, zeta potential, turbidity and refractive index), the stability of emulsions at refrigerator temperature was higher than at ambient temperature. The results show that chitosan and basil seed gum can be used to form coating layers around fat droplets such as food emulsions, which can inhibit lipid oxidation and increase the stability of essential unsaturated fatty acids. Also, after study of the physicochemical and physical stability examination, it was found that the three-layer emulsion was more effective in maintaining these characteristics over time than the other two emulsions.

Chicken meat is one of the most perishable foods. coating and modified atmosphere packaging are the new methods to increase its shelf-life. The present study was conducted to evaluate the effect of carrageenan edible coating () containing (Mentha longifolia) essential oil () under modified atmosphere packaging (% O ، % N ، % Co) on the quality of chicken meat during refrigerated storage. Samples were separated into three groups: uncoated (control), coated with carrageenan and coated with carrageenan contained essential oil (Mentha longifolia) were stored at refrigerator temperature for days and microbial (bacterial count of psychrotrophic and mesophilic), chemical properties (pH, total volatile nitrogen (TVN) and thiobarbituric acid (TBA)) and sensory characteristics (appearance, muscles elasticity, odor and color). Were evaluated at regular intervals storage time (days , , , , , , and). The results of the bacterial analysis showed that coating with carrageenan and carrageenan- essential oil coatings had significant effects on delaying the increasing trend of psychrophilic and mesophilic bacterial counts as compared to control. Chemically, carrageenan- essential oil treatment showed lower TBA, TVN and pH values than the other two groups during storage (P <). The carrageenan and carrageenan contained essential oil treatments that maintained sensorial factors at acceptable levels for and days respectively. According to the results, the carrageenan and carrageenan- essential oil coating could extend the shelf life of chicken fillets for and days.

In this study, Chia seed mucilage (CSM) as a new source and polyvinly alcohol (PVA) as co-polymer was used to prepare of nanofibers. Different solutions with CSM/PVA volume ratios of 100:0, 80:20, 60:40, 40:60, 20:80, 0:100 were prepared. Results show the increase in the CSM in the polymer solution increased the viscosity, electrical conductivity and viscosity of solution. Scanning electron microscopy (SEM) was to evaluate the morphology of nanofibers. Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) studies were used to evaluate chemical structure, crystalline structure and thermal characteristics of nanofibers of CSM/PVA. The crystallization index of CSM, PVA, and CSM/PVA nanofibers was 52%, 38%, and 44%, respectively. The non-formation of a new peak and presence of CSM and PVA peaks in the FTIR spectrum of the produced nanofibers are indicative of the lack of chemical reactions between CSM and PVA. Also, the addition of PVA to CSM improves the thermal resistance of the nanofibers.

Although fish oil is a very important source of omega-3 and its consumption is recommended in terms of nutrition, it cannot be used directly in the food system due to its instability. Therefore, its stability can be increased by converting the particle to the nanoscale. The aim of this study was to investigate the physical and chemical stability of omega-3 nanoemulsion at different temperatures and its antibacterial properties. For this purpose, fish oil containing omega-3 fatty acids was produced by high energy method in nanoparticles and its physical (particle size, zeta potential, viscosity, and physical stability) and chemical properties (pH and turbidity) were evaluated during storage at 4, 25 and 40 o C during 7 days, as well as antibacterial properties of fish oil nanoemulsion against two gram-positive and gram-negative bacteria. The results showed that the omega-3 nanoemulsion produced had the optimum stability at 25 o C. the optimal concentration of 4% of omega-3 nanoemulsions also showed antibacterial properties against the studied bacteria, especially Staphylococcus aureus.

Due to the high amount of pH, moisture and protein content, chicken meat is a sensitive product which could be a good host for pathogen and spoilage microorganisms. In the recent years there has been a remarkable attention to use natural preservative instead of chemical preservative among producers of food products. Different studies has shown rosemary essential oil contain antioxidant and antimicrobial properties. The present study was conducted to evaluate effect of rosemary essential oil (free and nanoemulsion) on chemical, microbial and sensorial quality of chicken fillet during refrigerated storage. Samples were examined in days of 0, 3, 6, 9 and 12. The results showed noticeable effects of both forms of rosemary essential oils in microbial, chemical and sensorial quality improvement. Moreover the results indicated that nanoemultion form of rosemary had significant effects on delaying the increase trend of psychrophilic, ,enterobacteriacea and mesophilic bacterial counts as compared to free form of rosemary (P<0.05). Furthermore The results of TVN, TBA and pH measurements indicated that nanoemulsion form of rosemary improved chemical quality of the samples in comparison with free form of rosemary during storage time (P<0.001).  Also in terms of sensorial characteristics, application of nanoemulsion essential oil lead to improvement of odor and overall acceptance factors compared to control group after twelve days of storage.

Natural preservatives are widely used in the food industry, today. In this study, the essential oil of Chavir plant (Ferulago angulate) was formulated as a water-dispersible nano-emulsion (diameter = 42 nm) using high pressure ultrasonic method. Analysis of essential oil composition showed that monoterpene hydrocarbons and oxygen monoterpenes comprised the main compounds of essential oil. The antimicrobial activity of essential oil and Nano-emulsion oil was evaluated with determination of the minimum inhibitory concentration (MIC) and the minimum biocidal concentration (MBC) as well as the disc diffusion agar methods on four pathogenic bacterial strains and two important fungi that cause foodborne illness. In addition, antioxidant activity was measured using DPPH free radical scavenging method and ABTS+ radical cation. The results showed that the antimicrobial activity of the essential oil increases when it is converted to Nano-emulsion due to easier access of Nano-emulsion to the bacterial cell membrane. In general, gram-positive bacteria displayed more susceptibility to the Nano-emulsion than gram-negative bacteria. Listeria monocytogenes was the most susceptible bacteria to the antibacterial activity of essential oils and Nano-emulsion. In addition, essential oils and Nano-emulsion had significant effects on inhibiting the growth of Aspergillus niger and Candida albicans. Although the antioxidant activities of essential oils and Nano-emulsion were significantly lower than the standard group (BHT), the antioxidant activity of Nano-emulsion was higher than in free essential oils using both methods. The results of this study showed that by converting essential oil to the Nano-emulsion of Chavir essential oil, its antimicrobial and antioxidant properties can be increased.

The present study was conducted to evaluate the effect of gelatin edible coating (4%) containing mint (Mentha spicata) essential oil (2%) on quality of chicken fillet during refrigerated storage (4o C). Samples were separated into three groups: uncoated (control), coated with gelatin and coated with gelatin contained mint essential oil (gelatin-mint). Samples were stored at refrigerator temperature for 21 days and microbial count (total aerobic mesophilic and psychrophilic bacterial counts), chemical properties (pH, total volatile nitrogen (TVN) and thiobarbituric acid (TBA)) and sensory characteristics (appearance, muscles elasticity, odor and color) were evaluated in 3 days interval. The results of bacterial analysis showed that coating with gelatin and gelatin-mint had significant effects on delaying the increase trend of psychrophilic and mesophilic bacterial counts as compared to control. Chemically, gelatin-mint treatment showed lower TBA, TVN and pH values ​​than the other two groups during storage (P <0.001). Also, the gelatin and gelatin-mint treatments maintained sensorial factors at acceptable levels for 6 days. Based on the results of the present study, gelatin coating did not have the ability to extend the shelf life of chicken fillets, on the basis of our results, the gelatin- mint coating may be a promising technology for the control of undesirable microbial, chemical, and sensorial changes during chicken fillet storage.

Shrimps are extremely perishable seafoods, which could threaten human health by causing foodborne diseases and intoxications. Therefore, seafood is generally stored at the temperature of -18˚C until consumption. The present study aimed to determine the safety of white shrimp in terms of biogenic amine toxicity and investigate some of the rapid chemical indices in this regard.  After preparation, the samples were stored at the temperature of -18°C for six months and analyzed monthly for the levels of trimethylamine nitrogen (TMA-N), biogenic amines (histamine, putrescine, and tyramine), and total volatile base nitrogen (TVB-N).  The values of TMA-N and biogenic amines had a rising trend during storage, while TVB-N had fluctuated values. Furthermore, putrescine and TMA-N had strong correlation-coefficients with time (r=0.933 and r=0.91, respectively). The biogenic amines remained below the limit value during the six-month storage.  Histamine, putrescine, and tyramine did not reach the toxic dose in the study period, posing no significant risk to human health during the appropriate storage of shrimp. Therefore, it is recommended that the values of TMA-N and putrescine be considered as potential quality indicators for frozen white shrimp.

Meat is prone to contamination and spoilage due to its composition and production. Therefore, in order to extend its shelf life, the use of antioxidant and antimicrobial compounds has always been the focus of researchers' attention.The present study was conducted to evaluate effects of edible chitosan (2%) coating containing Cuminum cyminum essential oil (1%) on the shelf-life of meat in modified atmosphere packaging at refrigerated storage. The meat samples were separated into three groups uncoated (control), treated with chitosan coated without Cuminum cyminum essential oil and immersed in chitosan coated with Cuminum cyminum essential oil.  Then Samples were packed in MAP (80% O2 and 20% CO2) conditions and stored at 4°C up to 21 days and evaluated periodically (on days 0, 3, 6, 9, 12, 15, 18 and 21) for microbiological (Total microbial counts, lactic acid bacteria, Enterobacteriaceae and Pseudomonas spp.) and chemical (pH, TBA and TVN) characteristics. Microbial analysis indicated that coating had significant influence (p<0.001) on reduction of increasing trends of Total microbial counts, lactic acid bacteria, Enterobacteriaceae and Pseudomonas spp.bacteria. From the aspects of chemical factors, the containing chitosan coating groups showed lower pH, TBA and TVN than those without coating. According to the results, chitosan coating significantly improved (P<0.05) quality of samples. This study also indicated that the effect of chitosan containing Cuminum cyminum essential oil on samples was to retain their good quality characteristics and extend the shelf life during refrigerated storage, which was supported by the results of microbiological, chemical, and sensorial properties.

Various methods have been developed to detect the presence of contamination with Coliforms and E. coli in foods. The pour plate technique using VRBA medium is confirmed as a standard method in Iran. The biggest disadvantage of this method is the need to spend a lot of time, high volume of laboratory operations, multiple stages and ultimately long time to achieve the results. Today, due to the mass production of various foodstuffs, the need for faster methods with high sensitivity to control the quality of food is necessary for the responsible oversight centers. The use of chromogenic medias is also one of the fastest diagnostic methods that have been developed. According to this matter, a comparative study was considered from the results of application of three chromogenic media and reference method in food quality control. Totally 100 samples of foodstuffs were evaluated for contamination to Coliform and E.coli using standard method and three chromogenic medias. Based on the obtained results, 86, 79, 85 and 80 samples were contaminated to Coliform using the standard method, Coliform Agar ES, ChromAgar ECC and Rapid E.coli 2/Agar respectively. Also, using four mentioned methods, contamination to E.coli was reported at 66, 80, 84 and 80, respectively. Cochrane test showed that there was no significant difference between the four methods in Coliform diagnosis (p>0.05). However, four methods did not have the same function in the detection of E. coli so that the chromogenic methods showed significant difference with the standard method (p< 0/001). But there was no significant difference between these chromogenic methods in detecting E.coli (p>0.05). According to the statistical analysis of present study, three chromogenic medias can be used instead of the standard method for the detection of Coliform, but the use of these chromogenic medias is not recommended for the identification of E.coli.

Due to the increasing consumption of ready-made foods such as burgers and their popularity among the public, the aim of the present study is to produce mixed burgers with different percentages of surimi and chicken minced and also, evaluation of the effect of modified atmosphere packaging (MAP) on the shelf life of the optimized burgers. First, surimi gels were produced and burgers formulated with 2 variables, the surimi and chicken minced, based on applying the Response Surface Methodology (RSM) several time up to achieving optimized formula. By analyzing the results of sensory evaluation using RSM software, the best formula was 37% chicken meat + surimi 63%, then the qualitative changes of the pre-formulated burger were studied for 27 days at 2 0C, which showed that the use of MAP significantly increased the storage time so that the burgers could be maintained with MAP packaging for up to 12 days.

Due to the increasing consumption of ready-made foods such as burgers and their popularity among the general population, the aim of the present study is to produce mixed burgers with different percentages of surimi and chicken minced and also, increasing the maintenance time of burgers by adding cumin and thyme essential oils (500 ppm) to burgers. First, surimi gel was produced and burgers formulated with the surimi and chicken minced based on applying the Response Surface Methodology. By analyzing the results of sensory evaluation using RSM that the best formula for burgers was chicken 37% + surimi 63%, then the pH, total volatile basic nitrogen, thiobarbituric acid and peroxide values and some microbiological characteristics were studied on selected burger for the duration of storage 27 days at 2 0C. The results showed that essential oils had a significant effect on the chemical and microbiological parameters in comparison with the control group (without essential oil) throughout the entire period. The use of thyme/cumin essential oils showed the good effect to extend the shelf life of fresh new formulated burgers. So that, in the presence of essential oils, the burgers can be stored for up to 9 days in terms of microbiological and chemical factors, although some of the chemical factors (TBA in all groups and TVN in the presence of essential oils) did not exclude the end of the maintenance period. The results show that optimum burger production with Surimi and chicken minced meat in the presence of essential oils is an appropriate option for the industries that sell their products as fresh meat products.

It is desirable to use a preservative with both antioxidant and antimicrobial properties such as edible acids for preserving of meat. The present study was conducted to evaluate the effect of acetic acids on the shelf life and keeping quality of turkey meat fillets at refrigerated storage temperature. Samples were separated into three groups; untreated (control), treated with acetic acid 1% and 0.5%. Samples were stored at 4±1°C up to 15 days and evaluated periodically (on days 0, 3, 6, 9, 12 and 15) for microbiological (mesophilic and psychrophilic bacterial counts), chemical (pH, peroxide value; PV and total volatile nitrogen; TVN) and sensory (external aspect, muscular elasticity, odor and color) characteristics. Microbial analysis indicated that coating had significant effects (P<0.05) in reducing the mesophilic and psychrophilic bacterial counts with at least a15 days extension of shelf life. In addition, the samples which treated with acetic acid 1% showed a lower amount of TVN, PV and pH compared to other groups as well as a better sensorial acceptability. The results of this study showed that the acetic acid can increase the shelf life of turkey meat fillet without adverse effects on the organoleptic properties.

Staphylococcus aureus (S. aureus) is one of the three major causes of food poisoning in the world, causing the disease in hundreds of thousands of people every year. Today, due to the production and processing the varieties of different foodstuffs, it is necessary to employ faster and more sensitive methods for controlling food quality, to gain the requirements of the regulatory centers. New qualitative control methods can be used for impedance and also for using chromogenic culture media. Their advantage over the reference method is the lack of high-volume laboratory operations and their relatively high rate of achievement. Therefore, evaluation of applying impedance, chromogenic and reference environments in the food quality control was considered. In the present work, 100 samples were evaluated for S. aureus infection by reference, impedance and chromogenic methods. Based on the results, 32, 21 and 57 samples were contaminated by S. aureus, respectively. The statistical analysis by SPSS16 software, using Cochran test showed that there is a significant difference between the three methods in detecting S. aureus (P<0.001). Statistical analysis showed that there is not a significant difference between reference and impedance methods, Although there is significant difference between the chromogenic technique and reference method (P>0.05), which means the reference and impedance methods have the same function and impedance can be used as an alternative technique for the reference method. Also the chromogenic technique could not be used instead of the impedance method.

Medicinal herbs have a long record of application in therapy throughout the world. Today, knowledge and public acceptability of the usage of herbal drugs is on a growing trend. However, medicinal plants may be contaminated with a variety of microorganisms. Enterococci are among nosocomial pathogens that are commonly found in large numbers in foods, plant materials, and vegetables. We aimed to detect enterococci contamination in industrial and traditional medicinal herbs by using standard and impedance methods. Eighty samples of industrial and traditional medicinal herb samples (40 per group) were analyzed for the detection of enterococci by using standard and impedimetric techniques. In general, Enterococcus contamination rate in herb samples was found to be 33.7% and 25% by using standard and impedimetric methods, respectively. McNemar’s test did not reflect any significant difference between the two methods in identifying Enterococcus contamination. Comparing the results of enterococci contamination obtained from the two methods, no significant differences were found between the industrial and traditional samples, although contamination was greater in traditional herb samples. The current standard methods for detecting enterococci are labor-intensive and time-consuming compared to advanced methods such as impedance. However, based on our results, sensitivity and specificity of impedance method could vary based on the type of samples being evaluated. However, it is recommended to perform further diagnostic tests for confirming our results.

This study was aimed to use of impedance technique and comparison of its results with reference method in traditional and industrial dried vegetables. In this study, 30 samples of traditional dried vegetable and 30 samples of industrial dried vegetable were tested for microbial counts by reference method of culture and Impedance device in accordance with the Instruction of Standards and Industrial Research Institute of Iran. The impedance method showed the minimum and maximum number of microorganisms in traditional samples were 4.80 × 104 and 1.40 × 106 bacteria per gram respectively. The minimum and maximum number of microorganisms in industrial samples were 6.00 × 102 and 7.00 × 105 bacteria per gram, respectively. The maximum detection time in impedance method in industrial and traditional dried vegetables was 20.24 and 23.68 hours, respectively and minimum detection time in industrial and traditional samples was 11.35 and 8.25 hours. The results showed determination coefficients of bacterial load in dried vegetable by regression equations were 0.9169, 0.9133 and 0.8861 in traditional, industrial and total of two method dried vegetables respectively. It indicates that high correlation was between reference and impedance methods for traditional and industrial dried vegetables. Microbial load in traditional and industrial dried vegetables was higher and lower than that of standard limit, respectively. Therefore, impedance technique could be used as an alternative method for control of bacterial load in dried vegetable.

Cattle transiently harbor Shiga-toxigenic Escherichia coli (STEC) in their gastrointestinal tracts, and many human infections result from ingestion of contaminated dairy products. The occurrence of STEC infections in human ranges from mild watery diarrhea to life-threatening conditions such as thrombotic thrombocytopenic purpura, hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS).
Isolation of STEC from unpasteurized dairy products as a source of human infections is the aim of this research.
In this study, after collecting 150 samples of unpasteurized dairy products from different parts of Ahvaz, primary enrichment, selective enrichment and conventional biochemical tests were done and the suspected DNA isolates were extracted by boiling. Confirmation of being toxigenic isolates was performed by multiplex polymerase chain reaction (mPCR) assay. The stx1- and stx2-specific primers were used in m-PCR.
Out of 75 isolates with lactose-fermentation ability, 11 E. coli strains were confirmed by biochemical tests. Two isolates (18.18%) were detected as carriers of stx2 gene by PCR.
Because of low infective dose, the presence of a low percentage of toxigenic E. coli in dairy products could be a grand public health risk, while the bacteria other than E. coli could be producing Shiga toxin which should not be ignored.

This study was carried out to evaluate shelf life, microbiological and chemical attributes of common carp (Cyprinus carpio) fillets treated by dipping in 1.5% lactic acid solution during refrigerated storage at 4 °C for 18 days. Mesophilic and psychrophilic counts, TVN (Total Volatile Nitrogen), pH, TBA and Expressible Moisture (EM) were carried out at 0, 3, 6, 9, 12, 15 and 18 days of storage. The microbiological and chemical analyses demonstrated significant reduction in mesophilic and psychrophilic counts, TVN and pH in treatment group (p

Escherichia coli is one of the most important members coliforms, which are important in terms of Pathogenicity and toxicity.The aim of this study using of Satureja khuzestanica essential oil as an antibiotic and natural preservatives in a food model (cheese UF) was after 60 days of storage. The data was analyzed using SPSS 16 and statistical tests One_Way ANOVA and Repeated Measures Define. The effect of Satureja khuzestanica essential oil (in 0.02% and 0.04% concentration) was studied on Escherichia coli with 104 cfu/ml in retentate consumed for cheese making with the blank sample which was not contained essential oil. The concentration of 0.02 and 0.04 % bacteria in the cheese containing the essential oil of 15 keeping up with the other days showed significant difference with the cheese without Satureja khuzestanica essential oil (p