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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.

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 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.

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 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.

The purpose of this study was to find a suitable solvent to produce saffron edible extract with improved chemical properties.

Dried and pulverized stigmas of Crocus sativus L. (10 g) was extracted with 300 ml of solvents including distillated water (DW), ethanol/DW, methanol/DW, propylene glycol/DW, heptan/DW and hexan/DW, for three days at 25°C and then centrifuged at 3,000 rpm. Then, the extracts were evaporated using rotary evaporator at 40°C. The fiber and solvent-free extracts were then analyzed by UV spectrophotometer to detect saffron quality parameters including crocin, picrocrocin and safranal.

Distilled water/ethanol mixture as the extraction solvent caused larger amounts of the plant constituents to diffuse out to the extract compared to other treatments and also control. Polar solvents including distilled water, ethanol and propylene glycol (except methanol) were more effective in extracting crocin, picrocrocin and safranal than non-polar solvents.

No research had been done on production of saffron edible extract using the solvent studied in this survey. The novelty of this research is high and the results can be used industrially.

The purpose of this paper is to detect total aflatoxin (AFT) in domestic and imported tea in Amol (north of Iran).

A total of 42 tea samples including 21 domestic and 21 imported tea samples of three popular commercial brands were purchased from retail stores and analyzed for estimation of AFT by ELISA technique. Data were analyzed by ANOVA using SPSS software.

All of the tea samples were contaminated with detectable amount of AFT ranging from 1.5‐16.5 ng/g. The average±SD concentration of AFT in domestic and imported samples was 7.1±2.96 and 6.11±3.94 ng/g, respectively, which is lower than national and EU standards (10 ng/g). The AFT content in 9.5 and 14.3 percent of domestic and imported samples was more than the limited concentration, respectively. There was no significant difference in AFT content of samples of different commercial brands (p>0.05).

No research had been done to detect and compare the AFT content of domestic and imported tea in Iran.

Grape juice concentrate (GJC) composition is affected by different factors including grape type and production conditions. So this study aimed to determine composition and nutrition value of GJC in eight cities in Khorasan province in north east of Iran in order to use the data in nutrition value tables.

The GJC samples (20) were supplied from local supermarkets in nine cities in Khorasan province in Iran. Total and soluble dry matter, total sugar, protein, fat, soluble fiber, ash and pH were determined according to standard methods. Nutritious minerals including calcium, phosphorus, magnesium and iron were detected using atomic absorption spectroscopy method.

The chemical properties of GJC samples were determined as follows: total dry matter 73.66 percent; protein 1.46 percent, total sugar 68.03 percent; soluble fiber 2.69 percent, ash 0.71 percent and fat 1.08 percent. The average values of pH and brix were, respectively, 4.25 and 65.5°. The mineral content was found as follows: calcium 817 ppm; sodium 0.9 percent; phosphorus 492 ppm; magnesium 1,704 ppm and iron 60 ppm.

The composition and nutritional value of GJC in Iran had not been determined before. The findings on nutritive properties of GJC can be used in nutrition value tables.

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.