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The aim of this study was to investigate the antibacterial activity of original extra virgin olive oil in Iran on some food borne pathogens.

Microbial analysis tests including disk diffusion and detections of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used. Also the chemical composition analysis of the oil was determined by GC-MS. Results of disk diffusion test confirmed antimicrobial activity for the oil in which S.aureus and E. coli were more resistant than L. innocua.

The MIC and MBC of organic extra virgin olive oil on the studied pathogens were in the range of 12.5-25 and 100 per cent v/v, respectively. The GC-MS analysis showed Z-9-Octadecenal (32.75 per cent), Oleic acid (15.78 per cent), Squalene (11.856 per cent), Phenol (8.392 per cent), Palmitic acid (1.884 per cent) as the main compounds (>0.7 per cent) in organic extra virgin olive oil, which have functional role in the biological activities.

This is the first study on organic extra virgin olive oil from Iran. According to the results, extra virgin olive oil has antimicrobial activity on foodborne pathogens.

The aim of this study was to investigate the presence of ochratoxin A (OTA) in chickpea samples in northern Iran and to study the effect of thermal treatment on ochratoxin content of the samples.

For this purpose, 32 chickpea samples were collected from retail stores of four cities in Mazandaran province in the north of Iran. Samples were soaked in potable water and cooked, respectively, for 3.5 and 4 h. Then the raw and cooked samples and the soaking water were analyzed for OTA determination by enzyme linked immunosorbent assay (ELISA) technique.

Results showed that six raw samples (18.75 per cent) contained detectable amounts of OTA by average concentration of 5.9±3.7 which is lower than national standards. The highest and lowest concentration of OTA in raw samples was 2.1 and 12.5 ppb, so chickpea is not a source for OTA poisoning. Increasing the time of cooking led to slight degradation of OTA but according to statistical analysis and LSD test, only after five hours, thermal treatment caused OTA to degrade significantly (p<0.05). During soaking and thermal processing, leakage of OTA to the water partly occurred so that the OTA content of soaking water is detectable.

Few research studies have been done on OTA detection in legumes and specially chickpea samples in the world and no research has been done to evaluate the effect of cooking process on OTA in chickpea.

Fungal growth on UF‐Feta cheese is one of the most important factors of consumer dissatisfaction in Iran. Propionibacterium shermanii metabolites was used as a biopreservative to retard this inconvenient. This research was done to determine the concentration of the metabolite that increases cheese shelf life with no adverse effect on sensory properties.

The cheese was manufactured according to the methods used in the Iranian UF‐Feta cheese dairy plants. The metabolite was used in the order of 0.5 and 1 per cent (w/w) of retentate weight. After incubation while reaching the required pH, cheese samples were stored at two temperatures including 4 and 25 degree C in which analysis was done during a period of 90 and 70 days respectively. Effect of the metabolite on shelf life (absence of visible fungi growth), total viable fungi, microbial load, pH as well as sensory properties including taste, odour, colour and overall acceptability was compared with the control (untreated sample).

Results showed that the shelf life duration of the cheese was extended by approx. 35–43 per cent. Total viable fungi was most efficiently reduced using the metabolite but there was no significant differences in microbial load. Addition of the metabolite didn’t affect pH of cheese at either temperatures compared with control. Results of sensory evaluation showed that the taste and odour of cheese containing 0.5 per cent of the metabolite was preferred as compare to the others (p<0.1). The intervension had no effect no effect on colour scores of cheese. The texture of control was better than the others (p<0.1).

In UF‐Feta cheese, the presence of fungi represents a major concern for cheese manufacturers. The results indicate that the fungal growth can be minimized using Propionibacterium shermanii metabolites without undesirable effects on sensory properties. The potential of the metabolite to inhibit yeast growth on UF‐Feta cheese was a new finding in this research.

The inclusion of natural antioxidants and nanoparticles into edible coatings can improve their structure, functionality and applicability in foods. This study aims to determine the antibacterial effect of new nano-composite based on bean pod shell gum (BPSG), silver nanoparticle (SNP) and herbal essential oil (EO).

For this purpose, BPSG (4 per cent w/v), SNP (0.5-1 per cent w/v) and Helichrysum arenarium EO (1-2 per cent v/v) were mixed. After preparation the edible film, the antibacterial activity was tested on five food-borne pathogenic bacteria in two categories including two-gram positives and three-gram negatives bacteria. The EO composition was determined by GC–mass spectrometry and the antibacterial activity was tested using disk diffusion test.

Results showed that gram-positive bacteria were more susceptible than gram-negative bacteria. Increasing Helichrysum arenarium EO and SNP content increased antimicrobial activity of the edible film based on BPSG, so that the treatment containing 2 per cent v/v Helichrysum arenarium EO and 1 per cent w/v SNP led to the highest inhibition zone (8.1-13.1 mm) compared to treatment containing 1 per cent v/v Helichrysum arenarium EO and 0.5 per cent w/v SNP with inhibition zone range of 5.4-9.9 mm and the difference was statistically significant (p = 0.41). Also, the chemical composition analysis of the EO identified a total of 38 compounds in which a-pinene (32 per cent), 1,8-cineole (16 per cent), α-humulene (15 per cent) and ß-caryophyllene (8 per cent) were the main fractions. Other separated components accounted less than 29 per cent of the oil.

In general, SNP and Helichrysum arenarium EO improved the functional properties including the antimicrobial activity of the edible film based on BPSG, which increases the potential to be used as active packaging for fresh products.

This study aims to analyze the levels of vitamin C, phenolic compounds and antioxidants in baby food. Providing nutritious food to the infants is essential for their growth and development. Baby foods are foods prepared from any suitable nutritive material and intended for feeding children after six months of age. The search for foods that meet the nutritional needs of children and that also promote aspects of health has increased on the part of parents.

A total of 17 different types of baby foods (2 brands) were purchased and the vitamin C content, total phenolic compounds (TPC) and antioxidant activity were determined. The authors also assessed the adequacy of labeling in accordance with regulatory parameters. Data was submitted to analysis of variance, and the means were compared by the Tukey test at 5% probability. Principal component analysis was performed to evaluate the results (phenolic compounds, vitamin C and antioxidant activity) from the multidimensional point of view.

In general, the labeling of baby foods proved to be within the legislation, but with confusing information for the consumer. BF7-AAPO (apple pulp and juice, papaya and orange juice), BF-BAO (banana, apple juice and oatmeal) and BF-AA (apple pulp and juice) showed the highest vitamin C content (20–28 mg/100 g; p < 0.001). BF-A (apple), BF-B (banana) and BF-AA showed the highest TPC (7–8.2 mg/100 g; p < 0.001). BF-CP (cassava-parsley), BF-PCBCP (potato, carrot, beef and cassava-parsley) and BF-PCBB (potato, carrot, beef and broccoli) showed the highest antioxidant activity (44–48%; p < 0.001). High value of TPC was related to high value of antioxidant activity in baby foods. In conclusion, vitamin C content in the baby foods was different from those reported on the labels and there was a direct relationship between the content of TPC and the antioxidant capability.

The objective of this work was to evaluate bioactive compounds and antioxidant activity in baby foods. So far, few papers have reported on the subject as the authors seek to know about essential nutrients. However, this knowledge is important because these compounds can decrease and/or prevent inflammatory processes in the body.

This paper aims to provide information on the different methods of aflatoxin (AFT) degradation in rice.

Crops that are affected by AFT contamination include cereals, oilseeds, spices and tree nuts. AFT in rice may harm health to great extent, and if not properly determined, may cause death. The production and occurrence of mycotoxins differ depending on the geographic and climatic and environmental conditions; however, these toxicants can never be removed completely from the food supply.

Mycotoxins are commonly present in cereal grains such as rice and are not completely destroyed during their cooking and processing.

No review on detoxification of AFT has been found in rice.

The study aims to describe the main classes of antioxidants existing in fruit, beverages, vegetables and herbs and the different extraction and application of antioxidants in food. Oxidative degradation of lipids, especially induced by reactive oxygen species, leads to quality deterioration of foods and cosmetics and could have harmful effects on health. A major challenge is to develop tools to assess the antioxidant capacity and real efficacy of these molecules. Recently, many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However, none of them has all the information regarding antioxidants (sources, extraction and application in food).

This paper tries to take a different perspective on antioxidants for the new researcher involved in this field.

Antioxidants from fruit, vegetables and beverages play an important role in human health, for example, preventing cancer and cardiovascular diseases and lowering the incidence of different diseases. A number of plant products act as scavengers of free radical species and so have been classified as antioxidants. Antioxidants are an important group of food additives that have the ability to protect against detrimental change of oxidizable nutrients and consequently they extend shelf-life of foods.

Most of the antioxidants present in foods are phenolic and polyphenolic compounds, but their efficacy in food for the prevention of oxidation or in the body for dealing with oxidative stress and its consequences depends on different factors.

This study collected the last finding in the field of sources and applications of natural antioxidants.

The aim of this study was to measure the apparent viscosity, flow behavior and density of melon juice as a function of temperature and juice concentration and to obtain simple equations to correlate experimental data.

Melon juice was concentrated in a rotary evaporator to 40±1, 52.5±1 and 65±1°Brix at 50°C, 80 rpm and stored at 4°C until analysis. Density of melon juice was determined with 25 ml pycnometer at 15, 25 and 35°C and was expressed as kg/m3. All experiments were conducted in triplicate. Experimental data were fitted to different models (linear, quadratic, exponential, quadratic exponential and polynomial) using Minitab 16. Significant differences in the mean values were reported at p<0.05. The flow behavior of melon juice was determined using a concentric cylinder rotational viscometer at shear rate range of 13.2-330 s−1 and temperatures of 15, 25 and 35°C. The experimental data were analyzed Slide Write V7.01 Trial Size (p<0.05) and the rheograms was plotted by Microsoft Excel 2007.

Results showed that the four-term polynomial model is the best model for computing density values from temperature and concentration (R2=0.999). The measured shear stress was within 1.69-780 Pa, corresponding to viscosity range of 0.016-0.237 Pa · s. Within the tested conditions, the concentrate exhibited a pseudo plastic behavior. Temperature had an inverse effect on shear stress and apparent viscosity.

No research had been done on production of melon juice concentrate.

The purpose of this paper was to determine the effects of the spinach extract and kiwi flavor on the physicochemical and organoleptic properties of yogurt.

A total of 48 yogurt samples including yogurts flavored with kiwi flavor (1, 2 and 4 percent) and colored with spinach extract (1.25, 2.5 and 4 percent) and a control yogurt (no kiwi flavor or spinach extract) were evaluated for chemical, physical and sensory properties during 21 days of storage. Data were analyzed by ANOVA using statistical analysis system.

Statistically significant differences (p<0.05) were found between the control and kiwi-spinach yogurts in terms of viscosity and syneresis. The addition of the spinach extract to yogurt resulted in an increase in the syneresis, and a decrease in the viscosity. During the storage, the values of the titratable acidity, viscosity and syneresis of yogurt samples increased, while pH decreased significantly (p<0.05). Yogurt enriched with 4 percent spinach extract and 4 percent kiwi flavor was more acceptable than the other samples, and high scored with respect to overall acceptability by panelists.

No research had been done to formulate and compare the sensory and physicochemical properties of kiwi-spinach yogurt in Iran.

The aim of this study was to test the presence of lead in raw milk from different regions of Mashhad (north‐east of Iran) through atomic absorption spectrometry (AAS).

A total of 60 samples of raw cow's milk were collected from the bulk holding tanks of 20 dairy farms of Mashhad and analysed immediately.

The mean level of lead content was 4.07 ng/ml, with a range from 0.02 to 44 ng/ml and a standard deviation of 7.54 ng/ml. The Pb concentration of one sample exceeded 20 ng/ml (maximum concentration accepted by Codex). Lead residue in 70 per cent of the samples was below 5 ng/ml and the Pb concentration in 10, 9.18 and 9.18 per cent of the samples was, respectively, in the range of 5‐10, 10‐15 and 15‐20 ng/ml. The results obtained for limit of detection (LOD) and limit of quantification (LOQ) in μgkg⁻¹ were, respectively, 0.65 and 2.1 while for the recovery 94.47 per cent.

The results reduce the public concern about lead contamination in milk in this region.

No research had been done to detect lead residue in raw milk in this region. Milk is not a major source for lead poisoning in Mashhad.