Showing 13 results for Golmakani
Farzaneh Vardizadeh, Sedigheh Babaei, Mahmood Naseri, Mohammad-Taghi Golmakani, Mina Esmaeili,
Volume 9, Issue 4 (11-2020)
Abstract
In the present study, the structural and antioxidant properties of fucoidan extracted from macroalgae (Sargassum and Padina) from the Persian Gulf coast were evaluated. The fucoidan was extracted by ethanol and hot water and after calculating the extraction yield, DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), scanning electron microscopy (SEM), and its monosaccharides by HPLC method were examined. The yield of fucoidan in Sargassum (4.2 ± 0.00%) was higher than Padina (2.98 ± 0.28%) (P < 0.05). The IC50 of DPPH free radical scavenging in fucoidan extracted from Sargassum and Padina were 0.1 and 0.14 mg/ ml, respectively, which were higher than BHT as a commercial antioxidant (P < 0.05). The rate of FRAP in both samples increased with an increase in the concentration of fucoidan. The SEM results showed that fucoidan from both macroalgae had strong structural cohesion and irregular surfaces, but Padina had more surface protrusions. The glucose, mannose and xylose sugars in different amounts were detected by the HPLC method, in which the amount of glucose and xylose sugars were higher in the fucoidan derived-Sargassum (P < 0.05). According to the results of the present study, the fucoidan extracted from the Sargassum and Padina can be a good alternative to an industrial antioxidant in food
Volume 13, Issue 14 (Second Special Issue 2014)
Abstract
In this paper, nonlinear bending of rectangular nanoplates of Graphene subjected to a transverse uniform load, with incorporation of the nonlocal effect of Eringen based on the first-order shear deformation theory (FSDT) of orthotropic plates and Von Karman nonlinear strains is investigated using differential quadrature method (DQM). In order to validate of the solution accuracy, the simplified results have been compared with results of two developed numerical solution methods and other available results. Comparisons show an excellent agreement between the results. Finally, effects of small scale parameter, aspect ratio, thickness of plate, load value, boundary conditions and efficacy of large deflection, on the maximum deflection and different deflections ratio for nonlocal theory of thin plate and nonlocal FSDT are investigated. Results reveal that among the considered parameters, just aspect of plate is the parameter of difference between two employed nonlocal theories and the small scale parameter has not any effect on the mentioned difference. Also, it is found that the small scale parameter has a noticeable effect on the decrease of deflection of nonlinear solution; so that, unlike the larger values of mechanical load, this parameter has less effect for long length of square plate.
Volume 13, Issue 60 (0-0)
Abstract
Volume 14, Issue 4 (7-2014)
Abstract
In this article, nonlinear bending analysis of sandwich circular plates with functionally graded face sheets subjected to transverse mechanical load is presented. The formulations are based on first-order shear deformation plate theory (FSDPT) and large deflection von Karman equations and nonlinear equilibrium equations solved by the dynamic relaxation (DR) method combined with the finite difference discretization technique. In order to verify the current work some obtained results are compared with the solutions reported in the literature and Abaqus finite element method. Finally, The influences of material constant k, boundary conditions, core-to-face sheets thickness ratio on the results are studied in detail.
Volume 14, Issue 5 (9-2012)
Abstract
Microwave-assisted hydrodistillation (MAHD) at three levels of microwave power (180, 360, and 540 W) and the traditional hydrodistillation (HD) were applied to obtain essential oils from Bunium persicum Boiss. (Black Zira). MAHD at 540 W started much earlier than that of HD (4 min vs. 38 min, respectively). By the time the extraction of essential oils started with HD, almost 50% of the total essential oils (2.15%, w/w yield) had been extracted with MAHD at 540 W. Analysis of the essential oils using gas chromatography-mass spectrometry showed that γ-terpinene (28.16-31.13%, w/w), cuminaldehyde (24.85-29.20%), ρ-cymene (14.67-16.50%) and limonene (6.13-8.28%) were their main constituents, with a similar composition both after HD and MAHD extraction. The antioxidant activity (reported as IC50) of essential oil extracted by HD was 9.31 mg ml-1 and those of MAHD at 180, 360, and 540 W were 8.62, 8.79, and 6.45 mg ml-1, respectively. Microwave irradiation did not cause any adverse effect on the antioxidant activities of the extracted essential oils, therefore, it can be used as a good alternative method to obtain essential oils from B. persicum.
Volume 16, Issue 2 (4-2016)
Abstract
Deep Drawing with rubber components of the conventional methods to remove the cost of manufacturing and is also an increase in LDR. The punch or matrix that is made of rubber.Deep drawing two sheet layers is one of the new methods to achieve desired properties in manufactured components. In this method two metal sheets together by glue connected to each other which together form the shape. Thinning control specially when the two materials or two different thickness is used, a single layer is different.In this paper the technique the initial gap used is between blankholder and fixed ring. In this study a square sample using die with rubber matrix with experimental and three-dimensional simulated, has been formed.In this paper, using the finite element method and model of hyper-elastic, three-dimensional simulations performed. Then, for verification,a die made with rubber components for cups square for both aluminum and sheets that by permutation method the practical experiments were perfromed and to compare the experimental and numerical results. Finally,with the help of response surface method collection simulations and practical experiments to evaluate parameters such as radius of punch, permutation the material type and the initial gap between the blank holder on the thinning, the force of punch and force blank holder performed.
Volume 18, Issue 3 (5-2016)
Abstract
The date fruit is of high nutritional value and its chemical composition is unique in providing energy, minerals, and vitamins for human. Date syrup, date concentrate and liquid date sugar are among semi-finished liquid products produced from low quality dates at industrial scale. In this research, some physicochemical properties of date syrup, concentrate, and liquid sugar in comparison with sucrose solutions were studied and the possibility of replacing sucrose with date liquid products was investigated. The results showed that the main chemical component of all three date products was simple sugars of fructose and glucose. Ash and protein contents of date liquid sugar were much lower than date syrup. pH values of date liquid products were also significantly different. Concentration of total phenolic and flavonoid compounds in date syrup was much greater than date liquid sugar. Overall, processing of date syrup to date liquid sugar reduced its nutritional quality while improving technological properties. It can be concluded that in choosing date liquid products as raw materials in food formulation, for the products that brown color of date liquid products does not affect the appearance of the final products, usage of date syrup or date concentrate is proposed. However, in other foods where brownish color of date syrup or date concentrate deteriorates sensory attributes of the final products, date liquid sugar is suggested. Date liquid products are also good candidates for high sugar products with sugar crystallization problem.
Volume 18, Issue 3 (5-2016)
Abstract
To reduce sucrose consumption in biscuits, Date Syrup (DS) and Date Liquid Sugar (DLS) were replaced with sucrose at different levels (0, 20, 40, 60, 80, and 100%) and physicochemical properties of dough and the resultant biscuits were compared. Dough pH and cohesiveness decreased while softness and adhesiveness increased with addition of DS and DLS. The pH, softness and adhesiveness of the DS dough were higher than the DLS samples. The DS and DLS biscuits had lower pH, higher ash and moisture contents than the sucrose biscuits. The DS biscuits had more ash content than the DLS sample. Addition of DS and DLS resulted in biscuits with higher density, spread ratio, harder texture, and darker color. These changes were more pronounced when DS was used. Sucrose replacement with less than 40% DS or 60% DLS resulted in biscuits with sensory characteristics similar to the control, and higher antioxidant and mineral contents.
Volume 18, Issue 118 (December 2021)
Abstract
In this study the influence of Alyssum homolocarpum seed gum (AHSG), basil seed gum (BSG) and different levels of banana peel flour (BPF) (0, 20 and 40%) on physicochemical properties of cakes containing date syrup (DS) or fig syrup (FS) was investigated. Parameters such as batter and cake pH, density, bostwick number, cake crumb and crust color, texture and sensory attributes were determined. The results revealed that increasing the banana peel flour decreased batter and cake pH, baking loss and sensory scores while increased batter and cake density, batter consistency, cake moisture, darkness and hardness. The influence of basil seed gum on moisture retention and consistency improvement was more significant than Alyssum homolocarpum seed gum. However, the cakes incorporated with Alyssum homolocarpum seed gum had lighter color and softer texture. Cakes manufactured by fig syrup had lighter color, softer texture and better organoleptic properties and fig syrup was a better replacer for sucrose in cake formulation.
Volume 20, Issue 4 (April 2020)
Abstract
In this research, the mechanical behavior of composites made with polyethylene matrix and wood powder reinforcement have been investigated. In order to improve the mechanical properties, the wood powder has been added to polyethylene at three levels of 30, 40 and 50 wt.%. The material was mixed using an internal mixer Haake and then the material was removed from the mixer and was granulated by a crushing machine. Finally, the granules were molded using an injection molding machine and tensile test specimens were made according to ASTM D638 standard and bending test specimens were made according to ASTM D790 standard. After preparing the specimens, a tensile and flexural test performed on them. The results of the mechanical tests show that the amount of elastic modulus increased with increasing the amount of wood powder so that the highest amount of elastic modulus was observed in the specimens containing 50 wt.% wood powder. Also, the highest strength in the tensile test was observed at the level of 30 wt.% of the wood weight and the highest flexural strength was in the 50% level of wood weight. Also, mechanical tests were simulated using Abaqus software.
Volume 21, Issue 7 (Supplementury Issue 2019)
Abstract
Date press cake is a by-product of date fruit juicing that has remained underutilized in the food industry. This is mostly due to the lack of information and technical knowledge about its chemical composition, nutritional value, health benefits and possible effects on the quality of food products upon inclusion. The main aim of this research was to determine the chemical composition, bioactive compounds and functional properties of date press cake to promote its food applications as an economical and available functional ingredient. The research was carried out on ground date press cake obtained from Shahani dates with two particle sizes of 355 µm (coarse) and 167 µm (fine). On average, Shahani date press cake contained 13.37% moisture, 4.92% fat, 6.35% protein, 11.74% crude fiber and 79.06% carbohydrate. Fructose was the main simple sugar, magnesium was the major mineral, oleic acid was the predominant fatty acid, and phenolic compounds were the main antioxidant. The chemical composition and functional properties of the date press cake were affected by its particle size. The coarse sample had lower fibre, oleic acid, total phenolic and flavonoid content and antioxidant activity than the fine sample. However, the fine sample had higher sugar and fat content and exhibited higher water holding capacity and solubility than the coarse sample.
Volume 21, Issue 146 (April 2024)
Abstract
In the present study, bioactive compounds were extracted from cotyledon of bitter orange (Citrus aurantium) seed, as a waste of citrus processing, using a microwave-assisted extraction method. The effects of four independent variables including microwave power (100-300 W), extraction time (5-15 min), sample weight (5-15 g), and solvent volume (100-200 mL) on responses of extraction yield, total phenolic content, total flavonoid content, free radical scavenging activity (IC50), ferric ion reducing antioxidant power (FRAP), cupric ion reducing antioxidant capacity (CUPRAC), and chelating capacity of extracts were investigated. Response surface methodology based on the central composite design was employed to investigate the effects of independent variables on the responses and also to optimize the extraction conditions. The optimum extraction condition included microwave power of 300 W, extraction time of 15 min, sample weight of 5 g, and solvent volume of 200 mL. Regarding the extraction yield, its amount increased significantly by increasing microwave power, extraction time, and sample weight, while it decreased significantly by increasing solvent volume. Also, the highest total phenolic content in the extract was observed at the lowest levels of microwave power and extraction time. Concerning the total flavonoid content in the extract, its amount increased significantly by increasing extraction time and solvent volume, while it decreased significantly by increasing sample weight. In addition, the CUPRAC of the extract increased significantly by increasing microwave power, extraction time, and solvent volume, as opposed to sample weight. In conclusion, microwave-assisted extraction can be suggested as a suitable method for extracting bioactive compounds from the bitter orange seed cotyledon.
Volume 22, Issue 1 (1-2020)
Abstract
Date Press Cake (DPC) is a by-product of date fruit juicing, which has remained mostly underutilized in food products. The main objective of this research was to investigate the viability of adding DPC in cake formulation. Thus, different levels (0, 10, 20, 30, and 40%) and particle sizes (210 µm= DPC210 and 500 µm= DPC500) of DPC were used in cake formulation. The results showed that DPC had higher fiber, ash, and fat content than cake flour. Increasing the level and reducing the particle size of DPC increased batter consistency, firmness, stickiness, cohesiveness and viscosity. Inclusion of DPC increased cake density, reduced pH and crust moisture content, but these were not affected by DPC particle size. The samples became harder and less cohesive as the level of DPC increased. DPC210 resulted in softer and less cohesive cakes compared to the DPC500. Addition of DPC improved the antioxidant content of the cakes, particularly when DPC210 was added. Overall, the sample produced with 10% DPC210 had acceptable sensory characteristics.