Journal of Food Technology and Nutrition
Year:2013 | Volume:10 | Issue:4 (40)|Papers Count:13

Introduction: Milk proteins are able to form gel under different situations such as heating, acidification, adding the enzymes and emulsifying salts. In this study, the effect of adding tetrasodium pyrophosphate (TSPP) and trisodium citrate (TSC) on physicochemical properties and rennet gelation time of unheated and heated skim milk was investigated.Materials and Methods: 2 to 10 mM TSPP and TSC were added to unheated and heated reconstituted skim milk. The pH, electro-conductivity (EC), and turbidity of samples were measured and upon the rennet treatment, the gelation time and water holding capacity (WHC) of treated samples were determined.Results: Based on our findings, addition of TSPP and TSC increased the pH and EC while it decreased the turbidity of the samples. Moreover, the presence of these salts extended the rennet gelation time of induced casein gels and gelation was only observed in the samples containing 2 and 4 mM TSC, and 4, 6, and 8 mM TSPP. The WHC of the samples was increased as well.Conclusion: TSPP and TSC resulted in dispersing the casein and forming new gel networks that can contribute to the improvement of some properties of milk products.

Introduction: Cake has been accepted as a snack food and part of daily meals for families nowadays and consequently its nutritional values have become important. The use of different components has been considered to improve the cake quality, shelf life and nutritional properties, in recent years.Materials and Methods: In this research, the effects of substituting 25, 50, 75 and 100% of sugar with molasses, on viscosity, density and pH of dough, volume and color of cake, are studied.Results: The results of these experiments showed that pH values of the dough don’t have a meaningful difference as compared to the control sample in all the cases examined. The viscosity decreased in all the samples containing molasses and the differences were significant. By increasing the level of substitution, density and volume of the product increased and decreased respectively. Evaluation of crumb color showed that all of samples are darker than the control.Conclusion: According to the results, the shelf life of the cakes might be increased and thequality and nutritional values might be improved by using molasses in the formulation.

Introduction: The knowledge of the mechanical properties of the fruits is an essential requirement for designing and optimizing the processing systems.Materials and Methods: In this study the mechanical properties of Pistachio nut and its kernel (Ahmadaghaei variety) such as rupture force, deformation till rupture point and rupture energy in three levels of moisture contents ( harvesting moisture content to final product moisture content; 35.6, 20.1 and 4.6% ) for safekeeping were calculated. In order to carry out this work, samples were under loading in direction of pistachio width within two parallel flat surfaces.Results: The results showed that the rupture force, deformation till rupture point and rupture energy are significantly affected by moisture content.Conclusion: By increasing moisture content from 4.6% to 35.6%, rupture force decreased from 112.6N to 65.7N for the seed and from 43.7N to 35.5N for the kernel and rupture energy decreased from 110.2mj to 95.5 mj for the seed and from 29.1mj to 19.5mj for the kernel. By increasing the moisture in mentioned limits, deformation till rupture point increased from 2.4mm to 3.4mm and 1.2mm to 2.2mm for the seed and the kernel respectively.

Introduction: Customers prefer to use natural extracts instead of the synthetic products. The consumption of floral waters and extracts has become quite popular as a mean to overcome and relieve some slight problems and sicknesses. The economics, yields and purity of the extracts are important factors to consider. Suitable analytical extraction and statistical methods are required to help us for experimental design.Materials and Methods: Floral water of Rosemary and Dianthus were obtained from traditional companies. Analytical grade solvents were purchased from Merck chemical company of Germany. Different solvents namely ethanol, methanol, carbon tetrachloride and chloroform were employed for the extraction. The extracts were injected to GC- MS apparatus and the peaks were identified.Results: Statistical analysis indicated that with minimum volume of solvent mixtures of (442 mL of ethanol, 20 mL of carbon tetrachloride) extraction is accomplished. More than 88% of compounds in Rosemary and almost 100% of compounds in Dianthus floral waters are characterized.Conclusion: In this study, response surface method has been applied for optimization and it was shown that this method could be designed for the best micro extraction condition with the application of lowest volume of solvents.

Introduction: Economic issues concerned with the demand for energy reduction and costs as well as improved quality of the final product in the bakery industry such as Wafer production is of great importance.Materials and Methods: In the present study the effects of applying different amounts of Protease (0.005-0.05% of the weight of flour), Hemicellulase (0.005-0.05% of the weight of flour), water reduction (0-20%), dough resting time (0-30 min) and the baking time (90-150 sec) on decreasing the waferbatter viscosity and some quality factors of wafer sheet were investigated and compared with the control sample. The amounts of batter viscosity, moisture, crispness and colour of wafer sheet were considered in order to evaluate the effects of various levels of protease and hemicellulas enzymes on the mentioned parameters. Optimisation of the process condition was conducted to determine the optimum formulation for producing wafer sheet.Results: The results were analyzed by Response Surface Methodology (RSM) and showed that optimal level of Protease enzyme, Hemicellulase enzyme, water reduction of formulation, dough resting time and baking time were 0.05%, 0.05%, 9.58%, 30 min and 135.17 sec, respectively.Conclusion: Protease and hemicellulase enzymes might be used in wafer sheet formulation and these enzymes have positive effects on dough and some quality factors of the final product such as moisture and crispiness. According to the variation of the flour quality, the production of wafer will beless dependenton the flour quality.

Introduction: Some mineral elements and heavy metals such as cadmium and lead if consumed regularly for a long period might be quite harmful to human health. In order to investigate the effects of domestic waste water on some mineral elements and heavy metals three plants namely rapeseed, alfalfa, and spinach were selected and the experimental works were carried out at research station at Islamic Azad University, Shahr-e-Qods Branch, in the syear 2011.Materials and Methods: A factorial experiment in randomized complete block design with three replications was implemented. Experimental factors including irrigation water with different degrees of pollution in four-level including the control were applied to rapeseed, alfalfa, and spinach plants.Results: The results indicated that there was significant differences between mineral elements namely potassium, phosphorus and sodium and the concentrations of these elements were highest in the plants that were irrigated with domestic waste water as compared to the control. The concentrations of cadmium and lead did not show significant differences among the sample examined.Conclusion: Irrigation with refined domestic waste water increased mineral elements such as sodium, potassium and phosphorus however significant differences were not observed among heavy metals.

Introduction: Osteoporosis is a skeletal system disease that is characterized by the low bone mass. The major consequence of this disease is bone fractures that occur more in weight bearing areas such as vertebrae, femur and even non weight-bearing joints such as wrist. The purpose of this study was to describe the relationship of body composition and osteoporosis in postmenopausal women.Materials and Methods: This cross-sectional study involved 50 postmenopausal women with osteoporosis, aged between 45 and 65 years who were recruited from Sina hospital in Tabriz. Body mass, fat mass, lean body mass, and bone mineral density at the spine and femoral neck were measured. Skinfold thickness was determined by caliper. Bone mineral density was measured by DEXA at the spine and femoral neck. Association between parameters of body composition and bone mineral density analyzed using a multiple regression analysis.Results: The body composition parameters indicated that only lean body mass had a significant relationship with osteoporosis in the femoral neck (R2 =0.271, P<0.05) and in the lumbar spine (R2=0.088, P<0.05).Conclusion: Our data indicated that from the body composition parameters, lean body mass is a powerful predictor of osteoporosis. Using this model, females at risk of osteoporosis can be identified; therefore early prevention and treatment are possible. This can also prevent unnecessary expenses of diagnostic procedures for people without the risks of osteoporosis.

Introduction: The aim of this study is to increase the shelf life and improve the quality of theproduct trade and export in Kerman Province by using coatings containing nanosilver particles and determining the optimal temperature for the storage of this product.Materials and Methods: In this study, nanocomposite LDPE films containing nanosilver particles were prepared (3%, 5%), Dates from Aziz Abad, Bam were packed in nano-coated coverage and were stored at 50, 20, 8 and 4 0C. The samples were examined after 2, 7, 21 and 53 days. The experiments concerned with pH, TSS, acidity and reducing sugar were carried out according to the approved methods by the Research and Industry Standard Institute of Iran.Results: By increasing the acidity, the pH values decreased for all the samples examined including the control. The acidity for the samples containing 5% nanosilver particles was less than the samples containing 3% nanosilver particles and the control. The control sample showed lower concentration of the reducing sugar as compared to the samples containing 5 and 3% nanosilver particles while TSS values that are related to the ripening of the samples were different for all the samples examined.Conclusion: The samples packed with 5% nanosilver particles and kept for 53 days at 40C showed better quality as compared to other samples.

Introduction: Legumes are rich in nutrients and are important source of food proteins. The biological value of legumes proteins is quite high due to having most of the essential amino acids in comparison with other sources.Materials and Methods: In this study we evaluated the chemical composition and functional properties (water and oil adsorption capacity, emulsifying and foaming properties) of Iranian legumes flours (red kidney bean, pea, mung, broad bean).Results: The results of proximate analysis indicated that flours obtained from legumes vary in composition. Chickpea flour with 33.4% protein content has the highest concentration of proteins among the flours examined. Water adsorption capacity ranged between 0.78 to 1.38 g/g, while oils adsorption capacity ranged between 0.79 to 0. 92 g/g. Emulsifying capacity of legumes were in the range of 16-26%.Conclusion: It was concluded that red kidney bean has the potential to be used as an ingredient in functional food formulations to enhance the nutritional values and functional properties of the product.

Introduction: purslane (Portulaca oleracea) is a member of the portulacaceae. Purslane has been described as a power food of the future because of its high nutritive and antioxidant properties. Purslane is listed in the world health organization as one of the most used medicinal plants and it has been given the term “Global panacea“. This study is concerned with the evaluation of physicochemical characteristics of the oil extracted from purslane seeds.Materials and Methods: In this research work purslane seeds were subjected to oil extraction. The extracted oils were subjected to a series of physical and chemical tests consisting of fatty acid composition, iodine value, colour measurement, saponification value, nonsaponifiable matter contents, acid value, peroxide value, phospholipids contents, metal contents, sterols and tocopherol compositions and contents.Results: The extracted oils accounted for 13.4% of the total weight of the seeds. The fatty acid profile of the isolated oil indicated that linoleic and a-linolenia- acids were the predominant fatty acids present. Examination of the isolated nonsaponifiable matter of the oil showed that a- tocopherol and b- sitosterol were the predominant tocopherol and sterol respectively.Conclusion: It was concluded that purslane seeds oil due to its high nutritive and antioxidant values might be regarded as a valuable oil for human consumption.