نشریه نوآوری در علوم و فناوری غذایی
پیاپی 22 (زمستان 1393)

This study was carried out to evaluate antioxidant and antimicrobial activity of followers of four Iranian varieties of safflower including Arak2811 Zarghan279، Isfahan14 and Varamin295. The flower were dried and extracted with methanol and water mixture. Ferric reducing antioxidant power and β-carotene bleaching assay were used to determine antioxidant activity. Antibacterial potential of extracts was determined with Broth Dilution method. Result showed Arak2811 had highest antioxidant activity in both experiment as Its FRAP value and EC50 in β-carotene bleaching were 0. 32±0. 02 Fe2+/mg dry weight and 2068. 44±15. 64 ppm respectively. Isfahan14 variety was more efficient in evaluation of antimicrobial activity. MIC against Staphylococcus aureus and Salmonella typhi were 30 and 60 mg/ml respectively.

Production of vinegar involves two steps alcoholic fermentation and oxidation of acetic acid. One of the most important factors that may affect the production of vinegar، is supplementary nutrient in the substrate that might accelerate the growth of microorganisms and increasing the yield. In this study، supplementation effect of addition two varieties of date palm seed powder including Kbkab and Mordasng as complete powder and free fat powder in quantities of 1، 2 and 3 percent and ash powder in quantities of 0. 1، 0. 2 and 0. 3 percent in apple juice with a brix of 18 was investigated in order to produce apple vinegar. The results showed that adding three different amounts of powder، increasesthe growth of yeast in the alcoholic fermentation and increases the production efficiency of alcohol at compared to the control sample. Increasing amounts of alcohol in this phase، leading to increase of substrate for acetic acid bacteria and increases the production efficiency of vinegar. Also، It was clear that not significant differences between the two varieties of dates from production of alcohol and acetic acid. It is probably because the chemical composition is similar in the two varieties of dates.

In this study the antimicrobial effect of essential oils of، Lamiaceae plants (Thymus vulgaris L.، Mentha spp. and Ziziphora tenuir L.) to prevent growth of pathogenic bacteria (Escherichia coli O157: H7) was studied specific medium (In vitro). For this purpose، three levels of concentration of essential oil (0، 0. 1، 0. 2 v/v) was chosen. Survival or decrease in the bacterial population in 20 treatments (3 repeated) for specific medium EMB (In vitro) during 24 hours and 14 days by measuring the kinetics of bacterial pathogens was investigated using response surface design. Results showed a reduction of Escherichia coli O157: H7 bacteria and optimal specific medium for reducing death or the kinetics of bacterial pathogens at concentrations of thymus essential oil % 0. 15 (v/v)، Mentha oil % 0 (v/v) and Ziziphora oil % 0. 15 (v/v) is the inoculation rate، which in most circumstances Reduction of Escherichia coli in 24 h 3. 39 Log/ml، 14 days in the 0. 15 Log/ml.

Macaroni is one of the cereal products with high nutritional value. This product has been widely used in recent years in the diet of the Iranian people. The purpose behind doing this research was reducing some of the available defects in Macaroni dough products and improving its quality. In this research، effects of salt amount in four levels (0. 5%، 1%، 1. 5% and 2%) on flour property (water absorption)، dough (dough development time، dough resistance، mixing tolerance index، resistance to extensibility، maximum resistance on extensibility، dough energy، alveograph pressure، extensibility، ratio of length to pressure and final product (moisture content، ash، cooking value and glazing value، adhesiveness، hardness، saltiness، taste and flavor) were used in randomized complete block designs in four replications. Also data analysis was performed by Minitab 14 software and statistical mean analyses were done by Duncan''s multi-range test in 5% level. The results indicated that the addition of salt caused increasing the flour water absorption، decreasing dough development time، dough resistance، increasing dough resistance on fermentation and dough resistance on extensibility. Adding Sodium Chloride led to an increase in the strength of flour and ionic strength and improving dough physical properties. Also addition of 1% salt significantly caused reduction of glazing value and a loss in cooking degree. Samples containing 1. 5% and 2% salt had the least glazing value. The least cooking loss quality was observed in 2% salted sample. The sample containing 1% salt proved the best in final product sensory evaluations.

Although Mozzarella cheese is one of Pasta filata cheeses which origin in Italy، due to increasing the popularity of Pizza and similar foods، it is being used widely throughout the world. The Mozzarella''s difference with many cheeses is that Mozzarella is mostly used as melted. Therefore، several of its properties like elasticity and firmness are important variables which are used for comparing the different technological procedures and are influenced by the chemical properties of cheese. So، improving theses properties is one of the most important aims of production procedure and the scholars proposed different methods for reaching to this aim such as using emulsifier. Therefore، this research aims at studying the effect of mono-diglycride on chemical، rheological and sensory properties of Mozzarella cheese. Mono-diglycride was added to cheese during cooking as 0. 1، 0. 3 and 0. 5 percent. Having done the chemical، rheological examinations (using texture analyzer) and sensory assessment as five-point hedonic، the results showed that in textural properties of cheese، there was a significant difference in the quantity of fat and protein of samples (in confidential level of 99%)، therefore، the sample contain 0. 1% emulsifier has the least amount of protein and most fat، texture analyser results، revealed that the most elasticity، softest texture and least required energy for rupturing belong to this sample and totally has the best properties.

Given the increasing consumption of meat products such as hamburger in large cities such as Tehran، quality control of these products is important. Because of increasing cost of red meat and difficult detection of adulteration in ground meat the replacement of red meat with cheaper proteins (plant proteins) in these products is clearly possible. So the aim of this study was to investigate the validity of labeling in premium hamburgers made of beef and detection of soybean protein as commercial fraud in premium hamburgers of Tehran city by sensitive and quick PCR method. 10 specified brands of premium hamburgers made of beef were collected from markets in Tehran city. DNA was extracted from raw beef، plant soybean protein as control samples and premium hamburgers. Then specific PCR was performed by species-specific soybean and beef primers. 118bp and 27 bp length fragments were amplified in all samples from soybean lectin gene and mitochondrial cytochrome b gene respectively. The results indicated the application of soybean in premium hamburgers unlike their labels.

In this research، some physical properties (including dimensions، mass، mean geometrical diameter، sphericity، surface area، volume and rehydration) and mechanical properties (including force، deformation، rupture energy and power) of Mamaei cultivar almond were measured. Results showed that average of geometrical mean diameter for Mamaei almond was 23. 66 mm and for its kernel was 14. 34 mm. The sphericity mean for the almond and its kernel was 0. 639% and 0. 523% respectively. By placing some samples of almond kernel in the water، rehydration of almond kernel was studied and its mathematical models were determined. After placing the sample of almond kernel in water for the interval between 9-13 hours، their total weight increased in relation to the first weight was 45-52% raised to 56% after 18 hours. Estimation of almond mass based on the dimension and volume was studied and mass model based on thickness was proposed as the best option for industrial and economical usage. Study of the effect of moisture on the statistic coefficient of friction for almond showed that by increasing the moisture، this coefficient increased and the type of surfaces had significant influence on the statistic coefficient of friction of almond in probability level of 1%. In studding of mechanical properties results showed that the effect of loading speed and direction and almond size on rupture force، energy and power in probability level of 1% were significant. By increasing loading speed rupture force decreases and deformation in rupture point increases. Minimum rupture force of almond in loading was in direction of axis (Z).

Lipid oxidation causes organoleptic and nutritional degradation of edible oils; to prevent this effect antioxidants are used. In current study، constituents of the essential oil of Myrtus communisas flavoring have been assayed and its antioxidant activity has been investigated. The essential oil of M. communis was extracted by a Clevenger-type apparatus and its chemical composition was analyzed by GC/MS. The essential oil was added to the frying oil of potato chips at 3000 ppm concentration and its antioxidant effect was analyzed on produced chips by peroxide value، TBA and acidity of the extracted oil of potato chips. BHA and TBHQ were used as general antioxidants at 200 ppm and oxidation reduction trend was assayed during 60 days storage. Also fried potato chips were analyzed from physical aspect (hardness and color). Results indicated that the essential oil had less peroxide value، TBA and acidity value than blank but during shelf-life its increase slope was more than blank (without any antioxidant). BHA، TBHQ and essential oil were caused more hardness in potato chips without any significant difference. From the color test aspect، samples containing BHA، TBHQ and essential oil had more lightness. According to the results of research، the essential oil of M. communis as natural antioxidant can be used in foods that are processed without heat.

The aim of this work was investigation of biodiesel properties that was produced under ultrasonic and traditional methods with homogenous and heterogeneous catalysts. According to this، transesterfication cause decrease in cinematic viscosity than waste oil (p<1%). The lowest cinematic viscosity is from biodiesel produced with homogenous and heterogeneous catalysts under ultrasonic transesterfication and in the standard range of ASTMD6751. The lowest density is from biodiesel produced with heterogeneous catalyst and ultrasonic condition. But in all biodiesels، density is higher than ASTMD6751. In the case of specific gravity، biodiesel produced under ultrasonic and with homogenous and heterogeneous catalysts have lowest specific gravity. But this factor in all produced biodiesels is higher than ASTMD6751.

The objective of this study was to investigate some physical properties of Japonica cultivar which is widely cultivated in Mazandaran، Iran in two types (paddy and whitened). Some physical properties were evaluated as a function of moisture content for paddy and whitened rice in the range of 10-18% w. b. Results show that physical properties of both rice types are influenced by moisture content. Data obtained for physical properties of paddy and whitened rice are respectively as follows: thousand seed weight 6. 69-7. 11 g and 4. 56-5. 02 g، length 3. 33-3. 49 mm and 2. 72-2. 95 mm، width 2. 15-2. 36 mm and 1. 85-2. 08 mm، thickness 4. 05-4. 32 mm and 3. 04-3. 35 mm، arithmetic mean diameter 4. 054. 32 and 3. 04-3. 35، geometric mean diameter 3. 62-3. 87 and 2. 83-3. 13، sphericity 54. 11%-54. 43% and 62. 60%-62. 35%، grain volume 5. 85-6. 68 mm3 and 3. 54-4. 30 mm3، surface area 35. 11-40. 10 mm2 and 21. 25-25. 81 mm2، true density 1103. 05-1203. 17 kg. m-3 and 1360. 44-1444. 05 kg. m-3، porosity 44%-51% and 34%-41%، angle of repose 22. 61-2768 angle and 16. 15-20. 29 angle، and static coefficient of friction 3. 96-4. 66. and 2. 98-5. 09 increased by increase in moisture content. Bulk density reduced from 614. 33 and 885. 00 kg. m-3 to 588. 33 and 850. 66 kg. m-3 respectively for paddy and whitened rice. All parameters increased by moisture increase except for bulk density showing decreasing trend. In all cases، data related to paddy rice (having bran) were more than whitened one except for bulk density. Altogether، a significant difference was observed between obtained results.

The probiotic products having some precious characteristics of nutrition and treatment are of the most controversial issues of the current field of the industry، nutrition and medicine. The use of low-fat mayonnaise and making them probiotic can help promote the public health due to the high consumption of this sauce. The aim of this study was primarily the investigation of the survival possibility of Lactobacillus acidophilus La-5 bacterium in low-fat mayonnaise including preservative and no preservative and then، assessing the impact of this bacterium on the microbiological and chemical properties and stability of the product during 8 weeks of refrigerating at a temperature of40c. 10cc sauce was inoculated with one gram of the bacterium powder containing 1010 bacterium per gram and thirteen serial dilutions were collected from each sample. Then the collected dilutions were transferred to the selected culture environment and meanwhile، inoculated plates and the control sample were incubated for at least 72 hours at 370c in aerobic conditions and the number of Lactobacillus acidophilus bacteria rose from 1*107 to 2. 2*107. The presence or the absence of the preservative doesn’t have any effect on microbiological، biochemical and sensory indicators of all treatments after 55 days of refrigerating. Adding probiotic Lactobacillus acidophilus bacterium to the sample of probiotic sauce didn’t make a significant difference to its textural stability and its sensory characteristics compared with the sample control، at a level of 5%، until the 55th day of refrigerating. Generally، all Lactobacillus acidophilus control and inoculation treatments have the production and storing ability in refrigerator for 55 days.

In this study، antioxidant activity and total phenolics of six tea type were analysed during various brewing time. For this purpose، Green، Kalemoorchei، Telepofaki، Chakoshsabz، Pashekaste، and red tea were brewed from 2 min up 10 min. Total antioxidant activity was determined as ferric reducing/antioxidant power (FRAP) assay. Total phenol content was determined using spectrophotometric technique، based on the Folin-Ciocalteau reagent and calculated as Gallic acid equivalents. The results showed the extraction of phenols increased with brewing time specially، up to seven minute and after that increased slowly. Total phenolic of black tea was more than red tea but less than green tea. Green tea followed with Kalemoorchei had the highest amount of phenol content (6. 076 & 5. 629 mM/g). The lowest amount was related to red tea (2. 234 mM/g). The brewing time had most effect on extraction total phenolics in black tea types. The antioxidant measurements showed that Chakosh-sabz tea and Taleh-pofaki had the highest and the lowest antioxidant activity، respectively.