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In this study, the effect of aqueous extract of green tea on the viability of probiotic bacteria including Lactobacillus acidophilus and Bifidobacterium bifidum and the sensory and physicochemical and functional properties of synbiotic yogurt was investigated during 4 weeks of storage. L. acidophilus and B. bifidum counts did not significantly change in yogurt containing 0.5% and 1% of the extract during storage. Also, the addition of the extract to yogurt highly increased the phenolic compounds, since the amount of phenolic compounds in yogurt containing 0.5% and 1% extract was 660 and 1,123 mg gallic acid/kg, respectively. In addition, a significant increase in the antioxidant activity of yogurt containing green tea extract was observed in comparison with the control. The amount of antioxidant activity increased during 4 weeks of storage, which reached to 4,193 and 7,337 mg BHT eq./kg in probiotic yogurt containing 0.5% and 1% extract, respectively. The acidity increased during 4 weeks of storage, while the pH decreased. Addition of the extract significantly increased the acidity of probiotic yogurt compared with the control (p

Among the main biodegradable food packaging materials, poly-lactic acid (PLA) is a commercially successful polymer used notably in the food packaging industry. In this study, active PLA films containing different percentage of anise essential oil (AE) (0, 0.5, 1 and 1.5% v/v) were developed, and characterized by physical, mechanical and antibacterial analysis. Based on physical examinations, thermal stability of PLA/AE films was greater than the neat PLA film, and the minimum water vapor permeability (WVP) was recorded for PLA/0.5AE film (1.29 × 10 11 g/m s), while maximum WVP was observed for PLA/1.5AE (2.09 × 1011 g/m s). Moreover, the lightness and yellowness of the composites were decreased by the addition of AE. For the PLA composites with 1.5% AE, the tensile strength decreased by 35% and the elongation break increased by 28.09%, comparing to the pure PLA. According to the antibacterial analysis, the minimum inhibitory concentrations of PLA/AE film were 5 to 100 mg/mL and the active composite could create visible inhibition zones of 14.2 to 19.2 mm. Furthermore, the films containing AE inhibited L. monocytogenes and V. parahaemolyticus in a concentration-dependent manner. The confirmation of the success of the incorporation of EOs into the PLA films was further evaluated using principal component analysis, where positive results were obtained. In this context, our findings suggest the significant potency of AE to be used as an antibacterial agent in active food packaging.

The effect of Auricularia auricula aqueous extract (AAE) on the survival of Lactobacillus acidophilus La-5 and Bifidobacterium bifidum Bb-12, and on chemical and sensory properties of yogurt was investigated during 28 days of storage at 4°C. The use of 0.05% of AAE improved the survival of L. acidophilus La-5 and B. bifidum Bb-12 about 0.35 and 0.58 log CFU/g, respectively. However, AAE in 0.1% concentration enhanced the survival of L. acidophilus La-5 and B. bifidum Bb-12 about 0.43 and 0.51 log CFU/g, respectively. Moreover, 0.1% concentration of AAE drastically increased antioxidant activity and total phenolic content to 115.30 mg BHT eq./kg and 1,057.6 mg Gallic acid/kg after 28 days, respectively. Addition of AAE to the yogurt significantly decreased sensorial acceptance while increased syneresis compared to the control group (p

Aflatoxin M1 (AFM1) is a 2B Group human carcinogens agent and introduces into the human diet by milk consumption. In the present study 257 raw, 143 pasteurized and 61 UHT milk samples were collecte...

Ethnopharmacological relevance The application of the herb Ziziphora clinopodioides Lam. in folk medicine and as a food additive has been recommended due to its many claimed bioactivities. Regardless of the plant benefits, its safety considerations are largely unknown. Aim of the study The aim of the present research was to determine the chemical compositions and cytotoxicity, genotoxicity, and mutagenicity potentials of the ethanolic extract of Ziziphora clinopdioides Lam. (EEZC). Materials and methods GC-MS and LC-MS analysis were used for chemical composition determination. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and trypan blue exclusion dye assays were used for cytotoxicity and the Comet assay was employed for genotoxicity assessment on human blood lymphocytes. Also, the Ames Salmonella/microsome test was carried out for the evaluation of mutagenicity. Results Pulegone was the main component of the n-hexane fraction. Different phenolic acids and flavonoids were detected by LC-MS. The cytotoxicity study indicated a conspicuous decline in human lymphocyte viability ranging from 52% to 100% as showed by the MTT assay and 67% up to 100% by the trypan blue assay, at 1 and 10 mg/mL, respectively. The Comet assay results revealed a dose dependent genotoxicity, in so much as 90% and 98% of the cells were screened as damaged at concentrations of 5 and 10 mg/mL, respectively. An incidence rate of 8% and 13% of grade 4 damage was observed at 5 and 10 mg/mL, respectively. Additionally, the DNA damage index (DI) was elevated dose-dependently by a rising concentration of the extract, wherein the DI at 10 mg/mL concentration was 2.22, which was 22 times greater than that of negative control, and even more than positive control. The Ames test exhibited no signs of mutagenicity for neither Salmonella typhimurium TA98 nor TA100 strains, accompanied or unaccompanied by S9 metabolic activation. Conclusion Results indicated a dose-dependent cytotoxicity and genotoxicity potential of the EEZC on human lymphocytes, suggesting that this plant should be used with caution by consumers, even in the food and pharmaceutical industries. Since the plant usage in daily life continues to increase due to its ever growing phytotherapical and phytonutritional properties, it may pose a health risk by its high concentration's uptake. Although no mutagenicity of this extract was observed in this study, further research is recommended to clarify the mutagenic risks of this herb.

Fresh proteinaceous products with animal origin have a short shelf life. Therefore, this study was done to evaluate the effects of novel films based on the combination of gelatin and nanochitosan incorporated with different concentrations of Zataria multiflora Boiss. essential oil (ZMEO) (0, 0.3, 0.6 and 0.9 % v/v) against two food borne pathogens including Listeria monocytogenes and Salmonella Typhimurium. Afterwards, the effect of films on the microbial, chemical, and organoleptic properties of chicken breast meat was evaluated during refrigerated storage for a period of 14 days. Based on the in vitro findings, the pure gelatin-nanochitosan (GNC) film or GNC film containing different concentration of ZMEO had antibacterial activity against L. monocytogenes, whilst only GNC films containing 0.6 or 0.9 % ZMEO showed antibacterial activity against S. Typhimurium. Also, results showed that the microbial population of chicken breast meat wrapped with GNC films containing ZMEO decreased at least 2 log CFU/g compared to control (P

Rye ( Secale cereale ) is one of a number of cereal species that grow wild in the northwest of Iran, Turkey, and Central Asian countries. It is revealed that sprouts possess higher vitamins, antioxidant, flavonoids and fiber than grains. For evaluation of the potential prebiotic activity of rye sprout extract (RSE), the grains were soaked in water, germinated and dried by a freeze-dryer. The in-vitro viability and relative growth ratio (RGR) of probiotic bacteria, as well as their antimicrobial activities and their retention in synbiotic yogurt during 56 days cold storage in presence of RSE, were investigated. The sensory properties (odor, color, texture, taste and overall acceptance) of symbiotic yogurt with different amounts of RSE in comparison with control group were evaluated. The results showed that adding various concentrations of RSE increased the viability of both Lactobacillus acidophilus and Bifidobacterium animalis (p B. animalis was better than L. acidophilus . Comparison of RGR of treated samples indicated that adding RSE even 0.25% can increase the growth and survival of probiotic in comparison with control. The results also showed that adding of RSE promoted the antimicrobial activities of probiotics. In synbiotic yogurt, probiotic populations remained higher than the minimum recommended therapeutic dose for an extended period of cold storage. There was no significant difference between sensory parameters of control specimens and synbiotic yogurt. According to our results, the synbiotic effect of RSE and probiotics highlights the potential application of RSE as a prebiotic in dairy and other functional products.

Major databases were searched until January 2019 and 77 eligible studies were included in the meta-analysis to estimate the overall mean of AFM1 in milk in Iran. The mean of AFM1 levels was obtained 55.97 ng/kg (95% CI: 50.09-61.84). However, the pooled estimated mean of AFM1 levels in milk were 94.58 (95% CI: 70.24-118.92), 59.19 (95% CI: 51.84-66.54) and 35.23 ng/kg (95% CI: 31.53-38.92), considering 4, 55 and 18 TLC, ELISA and HPLC-based studies (including 354, 9224 and 2606 samples), respectively. Also, there is a wide variation of AFM1 levels among different geographical regions which were the highest in northern (88.77 ng/kg). The AFM1 contamination of milk taken from the areas with humid climate was higher than the arid climate. AFM1 Levels were the highest in winter (48.70 ng/Kg). The level of AFM1 in pasteurized, raw, and UHT milk were 49.76, 55.08 and 94.81 ng/kg, respectively.

Milk has been regarded as a unique source of food for all ages but when it is exposed to various contaminants including lead, it is considered as a risk to humans. Therefore, it is important to monitor lead pollution in foods. In this study, 85 samples of raw cow milk were obtained from 85 dairy farms of Lorestan province in Iran. After the digestion process, the atomic absorption method with graphite furnace was applied. The mean level of lead content was 3.24 ± 1.31 ppb, ranging from

The present study aimed to isolate lactic acid strains from 105 camel milk samples from 6 provinces of Iran to investigate their probiotic, technological, and antioxidant properties. Seven identified lactic acid bacteria strains by 16S rRNA gene sequence analysis were Enterococcus faecium MN994352, Lactococcus lactis MN994342, and MT032418, Leuconostoc mesenteroides MT032416, MN994377, MN994378, and MT032415. The results showed that the studied strains successfully met all of the criteria. It has also been observed that bovine milk has a positive effect on the survival of lactic acid strains in the simulated gastric fluid. Great ability in co-aggregation with pathogens was observed in the auto-aggregation capable strains. Among the investigated food pathogens, Staphylococcus aureus was the most susceptible pathogen to the tested probiotic strains. The results also showed that all strains had strong antioxidants, lipolytic, and proteolytic activity, as well as a great ability to produce exopolysaccharide. According to technological analysis, the isolated strain could be used as a starter or co-culture to improve the rheological properties of food products, to enhance the total antioxidant status, and to reduce oxidative stress markers.

In this study, 22 Lactobacillus plantarum strains isolated from Siahmazgi traditional cheese were evaluated using different tests including resistance to low pH (1.50 and 2.50) and bile salt (0.50 and 1.00%), growth kinetic at low pH values and survival under simulated gastric and intestinal fluids. All the strains retained their viability at pH 2.50. However, the survival of all of the isolates was decreased at pH 1.50. Ten out of 22 strains which were able to tolerate low pH were selected for further investigations. All the selected isolates were able to grow at low pH. Strain F2 showed the highest specific growth rate. Five out of 10 isolates showed a significant decrease in bacterial count varied from 2.00 to 7.00 log CFU mL-1 during 3 hr exposure to 0.50% bile salt, while five isolates represented resistance to 0.50% bile during 3 hr. A significant reduction was observed in survival of all of the isolate at 1.00% bile salt concentration. Furthermore, viability of the selected isolates was lowered during 1 hr incubation under gastric conditions, while it remained unchanged within next 2 hr. Although, no significant changes were seen in bacterial count of the selected isolates during 1 hr of exposure to simulated intestinal condition, the survival of the isolates was relatively reduced after 3 hr. In conclusion, five out of 22 examined L. plantarum isolates showed appropriate resistance properties, therefore, could be good candidates for further examinations including functional and safety evaluation supporting their use as probiotics.

In this study, the antibacterial properties of Pimpinella anisum essential oil (PAO) were evaluated against six food‐related bacteria. Afterward, the effects of different concentrations of PAO on microbial, chemical, and organoleptic properties of minced beef were evaluated during refrigerated storage. Based on the findings, PAO was effective against all of the tested strains, where minimum inhibitory concentration of Listeria monocytogenes was 0.015% (v/v) and this value was 0.12% (v/v) for Vibrio parahaemolyticus and Salmonella typhimurium. At the end of storage time, the microbial population of samples treated with 0.5% v/w PAO was decreased approximately 1–2 log CFU/g compared to control (p

Major databases were searched until January 2019 and 77 eligible studies were included in the meta-analysis to estimate the overall mean of AFM1 in milk in Iran. The mean of AFM1 levels was obtained 55.97 ng/kg (95% CI: 50.09–61.84). However, the pooled estimated mean of AFM1 levels in milk were 94.58 (95% CI: 70.24–118.92), 59.19 (95% CI: 51.84–66.54) and 35.23 ng/kg (95% CI: 31.53–38.92), considering 4, 55 and 18 TLC, ELISA and HPLC-based studies (including 354, 9224 and 2606 samples), respectively. Also, there is a wide variation of AFM1 levels among different geographical regions which were the highest in northern (88.77 ng/kg). The AFM1 contamination of milk taken from the areas with humid climate was higher than the arid climate. AFM1 Levels were the highest in winter (48.70 ng/Kg). The level of AFM1 in pasteurized, raw, and UHT milk were 49.76, 55.08 and 94.81 ng/kg, respectively.

In this study, the chemical and microbiological properties of Siahmazgi cheese, an Iranian artisanal cheese made of unheated ewe and goat milk without addition of starter culture, were evaluated. The pH of the samples ranged from 4.76 to 5.18. The average numbers of total viable count and lactic acid bacteria (LAB) in cheese samples were 3.7 × 106 and 6.9 × 106 cfu/g, respectively. Coliforms and Enterobacteriaceae were absent in all the samples. A total of 125 LAB isolates were selected according to their Gram-positive and catalase-negative characteristics, out of which 23 strains were cocci and 102 were lactobacilli. Identification of the selected isolates was done through biochemical tests and 16s rDNA sequencing. Isolated strains were identified as Lactobacillus plantarum group (41.6%), Lactobacillus brevis (39.2), Lactobacillus parabuchneri (0.8%), Enterococcus faecium (13.6%), Enterococcus durans (3.2%) and Pediococcus parvulus (1.6%). The results of this study showed the microbiological diversity of traditional Siahmazgi cheese. Practical Applications Exploring the microbiological diversity of traditional dairy products is required for selection of appropriate strains to manufacture the products with consistent quality and original taste on industrial scale.

This study was aimed to produce liquid and dried kashk as a traditional dairy-based product on an industrial scale. Furthermore, the microbial, chemical properties as well as the proximate composition including pH, moisture, salt, fat, protein, total volatile nitrogen (TVN) and peroxide value (PV) were assessed after 1, 10 and 20 days of cold storage (7 °C). Also, the samples from traditional dairy products such as yogurt, doogh, dried kashk, and lolek were collected, and the diversity of lactic acid bacteria (LAB) was determined as L. lactis subsp cremoris, Streptococcus thermophilus, L. lactis subsp lactis, Lactobacillus plantarum, Lactobacillus helveticus, Lactobacillus bulgaricus, Lactobacillus casei, and Lactobacillus fermentum. The mean values of fat, protein, and TVN for dried and liquid kashk samples were measured as (7.4 ± 0.7, 2.7 ± 0.1%), (51 ± 3.8, 8.7 ± 0.6 g/100 g) and (15.3 ± 3.9, 14.9 ± 4.1 mg/100 g), respectively. The microbial analysis revealed yeasts and molds were the most prevalent microorganisms in both types of kashks, while no Coliform, Escherichia coli, and Staphylococcus aureus bacteria were found in all samples. In conclusion, the selected species from traditional products which presented a specific property may provide a wide range of genetic variants to design modified species with desired characteristics.

BACKGROUND In this study, chitosan-coated alginate beads were produced with different concentrations of chitosan and alginate to evaluate the survival of encapsulated Lactobacillus rhamnosus GG during exposure to adverse conditions in gastrointestinal simulated juice and heat processing. RESULTS The encapsulation yield of different encapsulation treatments was between 25 and 53.2%. Although there was a drastic decrease in pH within 48 h of incubation in MRS medium inoculated with free and encapsulated bacteria, no significant changes (P > 0.05) in bacterial count were observed among different encapsulation treatments. Moreover, the survival rate after gastrointestinal juice exposure of all prepared beads was 10–87 times greater than that of free cells and was significantly enhanced by increasing chitosan and alginate concentrations. The encapsulated bacteria survived significantly (P < 0.05) better than the free cells during heat exposure at 55, 60 and 65 °C: free cells experienced about 5 log cycles reduction after heat treatment at 65 °C for 30 min, whereas 40 g L−1 alginate/10 g L−1 chitosan-encapsulated L. rhamnosus was reduced by only 2.55 log cycles. CONCLUSION Encapsulation effectively protected L. rhamnosus against heat treatment and gastrointestinal conditions, and this effect is important in delivering sufficient numbers of viable probiotic bacteria to the gastrointestinal tract. © 2013 Society of Chemical Industry

In the present work, the effects of Zataria multiflora Boiss. essential oil (EO) against growth and citrinin production by Penicillium citrinum ATCC 1156 were evaluated in culture media and mozzarella cheese. The growth was completely inhibited at 200 ppm on potato dextrose agar, and minimum fungicidal concentration of the EO was estimated at 400 ppm. EO strongly suppressed the growth and citrinin formation in media with a dose-dependent manner. At 200 ppm in yeast extract sucrose (broth) flasks, mycelial dry weight and citrinin production significantly reduced by 87.5 and 92.4%, respectively (P

In this study, the effect of Cuminum cyminum L. essential oil (EO) and Lactobacillus acidophilus (a probiotic) on growth of Staphylococcus aureus in white brined cheese was evaluated. The experiment included different levels of EO (0, 7.5, 15 and 30 µL/100 mL milk) and L. acidophilus (0 and 0.5%) to assess their effects on S. aureus count during the manufacture, ripening and storage of Iranian white brined cheese for up to 75 days. The significant (P

The effects of different concentrations of Zataria multiflora Boiss. essential oil (EO: 0, 5, 15 and 30 μl 100 ml −1 ) and nisin ( N : 0, 0.25 and 0.5 μg ml −1 ), temperatures ( T : 25 and 8 °C), and storage times (up to 21 days) on growth of Salmonella typhimurium and Staphylococcus aureus in a commercial barley soup were evaluated in a factorial design study. The growth of S. typhimurium was significantly ( P N concentrations at 8 °C. For S. aureus , the viable count was significantly ( P N concentrations and their combinations, incubated at both storage temperatures. The mechanism of the antimicrobial action of EO, N , and their combinations against cell membranes of the tested organisms were also studied by measurement of the release of cell constituents and by the electronic microscopy observations of the cells. The significant increase of the cell constituents’ release of both organisms was observed as a result of treatments with EO and EO in combination with N . Electronic microscopy observations revealed that the cell membranes of S. typhimurium treated by EO and EO in combination with N were significantly damaged, while cells treated with only N looked similar to untreated cells. The electron micrographs of treated cells of S. aureus with EO, N , and their combination also showed important morphological damages and disrupted membranes.

Zataria multiflora Boiss., known as Avishan-e-Shirazi in Iran, is a member of the Lamiaceae family. Oxygenated monoterpenic compounds, mainly thymol and carvacrol, are major components of the essential oil (EO) of this plant. The derivatives of this plant, especially its EO, have been long used in folk medicine and healthcare as a decoction, infusion, or vapor. New potential areas of application of this EO in modern medicine have emerged due to increasing attention to different pharmaceutical effects of this EO demonstrated by many experiments. Although it is traditionally used as flavoring agent in a variety of foods, it is now well evident from numerous studies by many food science researchers that this EO possesses different biological effects including antibacterial, antifungal, antioxidant, and antiinsect properties. These findings introduce Z. multiflora Boiss EO as a promising food preservative to improve the safety and quality of food commodities.

UNLABELLED The effect of Zataria multiflora Boiss. (Z. multiflora) essential oils (EO) on biogenic amines (BAs) production and microbial counts in Gouda cheese has been investigated. Zataria multiflora was added to milk in different concentrations (0·05, 0·1, 0·2 and 0·4% (v/v)). The BAs (tyramine and histamine) were measured by RP-HPLC, following extraction from the cheese. Various microbiological analyses (aerobic mesophilic bacteria, enterococci, mesophilic lactobacilli, Enterobacteriaceae, lactococci and yeasts) were performed during ripening using the viable plate count method on specific culture media. The overall acceptability of cheeses was investigated by seven panellists. All the samples containing different concentrations of EO were acceptable to the panellists. Also, Gouda cheeses with 0·2% Z. multiflora EO showed the highest acceptability among all the samples. At the end of maturation period, 0·1, 0·2 and 0·4% Z. multiflora EO reduced tyramine and histamine significantly to 5%, 22% and 44% for tyramine and 14%, 29% and 46% for histamine, respectively, when compared to the control group. The increase of Z. multiflora EO concentrations led to further decrease in BAs content and microbial counts. The maximum microbiological reduction was observed in yeasts, and minimum microbiological reduction was seen in Enterobacteriaceae counts. Zataria multiflora EO could be used for reduction of BAs and also as a flavouring agent in Gouda cheese and could contribute to consumers' health. SIGNIFICANCE AND IMPACT OF THE STUDY The presence of biogenic amines in cheese has a serious impact on public health. Besides, there is growing concern about the use of chemical preservatives and the food industry is looking for new natural preservation methods. Zataria multiflora Boiss. essential oil is well known for its antimicrobial effects, and we attempted to reduce biogenic amines formation in Gouda cheese using Z. multiflora Boiss. essential oil as a natural additive. Furthermore, the desirable organoleptic qualities such as flavour, odour, texture and colour were achieved by adding Z. multiflora Boiss. to cheese.

The effect of different concentrations of Zataria multiflora Boiss. essential oil (EO; 0%, 0.005%, and 0.015%), nisin (0, 0.125, and 0.25 microL/mL), and their combinations on the production of staphylococcal enterotoxin C (SEC) and alpha-hemolysin (alpha-toxin) by Staphylococcus aureus at different inoculation levels (10(3), 10(4), and 10(5) cfu/mL) in brain heart infusion broth during storage at 35 degrees C for up to 43 days was evaluated. The SEC production was significantly (p < 0.05) inhibited and the hemolysis due to alpha-toxin was significantly (p < 0.05) reduced by EO concentration at levels 0.015% and 0.005%, respectively. Significant (p < 0.05) inhibitory effect of EO on SEC production at level 0.005% was observed when it was used in combination with nisin = 0.125 microL/mL. The significant (p < 0.05) synergistic effect of EO = 0.005% and nisin = 0.125 microL/mL was also observed as more reduction of hemolysis due to alpha-toxin than EO = 0.005% alone. Further, EO significantly (p < 0.05) prevented SEC production by S. aureus during the manufacturing process of a traditional Iranian white brined cheese (as a food model) even at its lowest concentration (5 microL/100 mL), in this study.

Background: The application of natural compounds including green tea extract (GTE) in food and pharmaceutical industries is limited. Encapsulation in nanoliposomes could be used as a delivery system to protect these compounds during processing and storage. Objective: In this study encapsulation of green tea extract in nanoliposomes and evaluation of its antibacterial, antioxidant and prebiotic properties were evaluated. Methods: GTE was encapsulated in liposomes by thin film layer method and reached to nanoscale with sonication. The prebiotic activity of 1% nanoliposomal GTE was evaluated on the growth of lactobacillus casei and bifidobacterium lactis in MRS broth medium. Furthermore, the antioxidant activity of nanoliposomal GTE was estimated by DPPH assay. The antibacterial activity of nanoliposomal GTE against Bacillus cereus (ATCC11778), Salmonella typhimurium 138 phage type 2, E. coli O157:H7 and Listeria monocytogenes (ATCC19118) was determined using well diffusion technique. Results: The mean diameter of nanoliposomes was about 44.7± 1.9 nm and had 0.203 ±0.014 polydispersity index. Entrapment efficiency of nanoliposomal GTE under the optimum conditions was 97%. Antibacterial activity of GTE was significantly increased after encapsulation in nanoliposomes. The strongest antibacterial activity of nanoliposomal GTE was seen against listeria monocytogenes with an inhibition zone of 16.2 mm while E. coli was the most resistance strain with an inhibition zone of 14 mm. Furthermore, the antioxidant activity of GTE was significantly increased after nanoliposome encapsulation since the IC50 value of nanoliposomal GTE was decreased to 1.78 &mug ml-1. Moreover, addition of 1 % nanoliposomal GTE enhanced the growth rate of Lactobacillus casei and Bifidobacterium lactis to a significant extent. Conclusion: Nanoencapsulation effectively enhanced beneficial properties of GTE.