---

---

The conditions for the refinement of clarified sugarcane juice, including temperature (50o, 60o and 70oC) and pressure (0, 0.5, 1 and 1.5 bars) by micro-filtration membrane technology were investigated. The raw sugarcane juice was initially pre-filtrated with lime and then the juice obtained (clarified juice) processed using a ceramic micro-filter mem-brane (0.2 micrometer). The characteristics investigated included brix, polarity (sucrose percent), turbidity, color and purity. The results showed that the effects of different proc-ess conditions with micro-filtration on reduction of turbidity and color were significant at probably <0.01 and probably <0.05, respectively. For other characteristics, no significant difference was observed. Finally, a temperature of 70oC and transmembrane pressure of 1.5 bar were determined as the optimum conditions for ceramic micro-filtration. Mem-brane processing at 70oC and 1.5 bars reduced the turbidity, viscosity and color of clari-fied juice 56.25%, 16.67% and 6.49%, respectively, and increased 0.87 units of purity.

---

Enzymatic acidolysis of canola oil through caprylic acid was investigated to produce certain medium chain Ttriacyliglycerol (TAG) structured lipids (SLs). Lipozyme TL IM, an sn-1,3 specific Thermomyces lanuginosa lipase, and Novozym 435, a non-specific Candida antarctica lipase, were utilized as the biocatalysts in a batch reactor. Reaction conditions were designed according to Taguchi’s approach, considering three levels of fatty acid to oil ratio (1:1, 2:1, and 3:1), three levels of enzyme load (4, 8 and 12%, w/w), three levels of temperature (45, 55, and 65°C) as well as three levels of reaction time (15, 30 and 45 hours). Results indicated that fatty acid composition of canola oil was modified by the above acidolysis reactions. The highest mole percent of caprylic acid incorporation (37.2 mole%) was obtained after 15 hours of incubation in the presence of Lipozyme TL IM at 55°C, fatty acid to oil ratio of 3:1 and at 12% of enzyme level. However, with Novozym 435 the highest level of incorporation (38.5 mole%) was obtained after 45 hours of reaction at 45°C, fatty acid to oil ratio of 3:1, and at 8% enzyme level. Novozym 435 was able to incorporate more caprylic acid in the oil than did Lipozyme TL IM. SLs prepared using either Lipozyme TL IM or Novozym 435 differed in terms of their TAG compositions. According to the obtained results, SLs produced by use of Lipozyme TL IM lipase contained higher levels of MLM-type (Medium-Long-Medium) triacylglycerols than those produced using Novozym 435 lipase (21.2 and 9.9%, respectively).

---

Barbari is a traditional flat leavened Iranian bread and one of the most popular breads consumed in Iran and some other countries in the Middle East. Barbari stales very fast and its shelf life is very short. Therefore, addition of bread improvers and anti-staling agents, such as hydrocolloids, is a suitable method for extending the shelf life of the bread. In the present study, the effect of various hydrocolloids including hydroxypropyl methylcellulose (HPMC), xanthan, and κ-carrageenan at 0.2 and 0.5% levels were investigated on dough rheological properties, fresh bread quality, and bread staling. Dough water absorption was increased by all hydrocolloids tested and HPMC had the highest effect. Application of all hydrocolloids, except κ-carrageenan, resulted in increase in dough development time (DDT). Only xanthan addition at 0.5% level showed an increase in dough stability, while the other treatments showed a reduction in the stability of the dough. Anti-staling effect was observed for HPMC and κ-carrageenan, but not for xanthan. The effect of hydrocolloid addition on some sensory indexes of bread such as upper surface and chew-ability was more pronounced than other indexes. Sensory analysis showed that all hydrocolloid addition treatments, except 0.5% xanthan, were able to improve the overall acceptability of the bread. The highest improvement in bread overall acceptability was brought about by HPMC. Hydrocolloid addition to the bread formulation could improve the sensory properties of Barbari bread and retarded the staling process. Based on the present study, the highest improvement in Barbari dough and bread quality could be obtained by the addition of 0.5% HPMC into the formulation.

---

In Sistan and Baluchestan province, unemployment rate has been increased from 9 percent in 1996 to 31.52 percent in 2006. Thus, in order to reduce unemployment rate and because of limitation of resources, the attention should be paid to activities, which create the highest employment opportunities. This research answers to these questions: What are the key economic sectors with regard to employment generation in Sistan and Baluchestan province? Do the growth-centered policies necessarily create the highest employment? In order to answer these questions, the linkage indexes related to production and employment, and input – output elasticities were calculated using the provincial input – output table in 2007. In addition, Multi – rank index (MRI) was calculated for the production and the employment generation in order to include all mentioned indexes simultaneously.  The findings show that the activities "Agriculture, hunting and forestry", "Mining", "Manufacturing", "Hotels and restaurants", "Wholesale and retail trade; repair of motor vehicles, motorcycles", "personal and household goods" and "Health and Social Work" are key sectors in creating employment. While key producing sectors are the "Agriculture, hunting and forestry", "Manufacturing", "Electricity, gas and water supply", 'Hotels and restaurants", "Wholesale and retail trade; repair of motor vehicles, motorcycles", "personal and household goods", "Transport, storage and communications" and "other community, social, personal and family services". Therefore, growth-centered policies do not necessarily create the most employment opportunities.  

---

Accurate measurement of unsteady pressure fluctuations along a surface requires experimental set up with high spacing resolution and high frequency domain. Therefore, in recent decades extensive studies have been conducted on remote microphone approach. In this method, instead of using flash mounted sensors, they installed remotely and connected to the model surface through one or several continuously connected tubes. Surface pressure fluctuations will travel within the tubing in the form of sound waves and they will be measured when passing over the remote pressure sensor, mounted perpendicular to the tubing. In the present study, an analytical solution of sound waves propagation inside the rigid tubes is used for modelling of the remote microphone system and to investigate the effects of its parameters on dynamic response. In order to verify the accuracy of proposed modeling, the dynamic response of a typical remote microphone has been obtained through experimental calibration. Comparing the analytical and experimental results indicates high accuracy of the analytical modeling. Results show that changes in tubing diameter leads to occurrence of resonance and creating harmonics in two frequency regions. The amplitude of low-frequency harmonics depends on the length of the damping duct and decreases with increasing of its length. Instead, the amplitude and frequency of high-frequency harmonics depend on the length of the first tube and they decrease with the increase of first tube length. Also, Increase of the first and second tube lengths lead to an increase in phase of dynamic response of the remote microphone system.

---

The objective of this study was to evaluate the effects of pasteurization temperatures and cold shelf storage on chemical, microbial, and quality characteristics functional milk-carrot drinks. For this purpose, milk-carrot drinks based on cow milk were prepared with different concentration of carrot juice (10, 20, 30, 40, and 50%) and pasteurized at 65, 70, and 75 °C for 30 min. Physicochemical characteristic such as total acidity, pH, Sugar (total sugar, reducing sugar, and non-reducing sugar), total protein, coliform, pasteurization efficiency, stability, phase separation, and sensory parameters were measured during storage times (1, 4, 7, 10, and 13 d) at 4 °C. The results indicated that total acidity and pH of milk-carrot samples pasteurized at 70 °C had lower variation than other treatments during cold shelf. The highest non-reducing sugar content was belong to 50% carrot juice (75 °C) at 13 d and the highest reducing sugars was observed  at 4 d for all samples in pasteurization temperatures were. Pasteurization temperatures and storage time had not significant effect on total protein of samples with different carrot juice content. Pasteurization efficiency test showed that all of the pasteurization temperature-time treatments could completely inactivated alkaline phosphatase enzyme. But in coliform test, samples with 50% carrot juice (65 °C) at 13 d and 30% carrot juice (75 °C) at 13 d showed 3 and 12 colonies respectively. Stability test and phase separation indicated that all treatments during cold shelf had necessary stability. Sensory evaluation determined that samples containing 40 and 50% carrot juice had the highest total acceptation. I t could be concluded that the optimum  conditions for functional milk-carrot drink formulation, pasteurization and storage time for milk-carrot drink were 40 and 50% carrot juice substitution, 70 °C pasteurization and 10 d cold shelf stability respectively.

---

In the current study, the effect of seasonal variation on the type and percentage of phytochemical compounds of Artemisia fragrans Willd. essential oil was investigated. Herbal samples were collected in 4 different seasons and then their essential oils were extracted by the Clevenger type apparatus. In the following, the essential oil compositions of each season was analyzed by GC-MS apparatus. In total, 50 different compounds were identified in four sentential oil. The major components of the essential oil were camphor, thujone, and 1,8-cineole in different seasons. Also, the results showed that monotreptans were the major class of essential oil compounds in September (91.87%), December (90.55%), May (96.32%) and July (95.4%). The highest amount of phenolics (5.49 mg GAE/g) and antioxidant capacity (28.98%) were observed in essential oil of Septebmer.   Antibacterial effects of the different essential oils using paper disc diffusion method were carried out on Escherichia coli, Proteus vulgaris, Klebsiella pneumonia, Staphylococcus aureus, and Bacillus subtilus. Based on the results of the study, gram negative bacteria (E. coli, Proteus vulgaris, and K. pneumonia) were more susceptible to artemisia essential oils in comparison with gram positive bacteria (S. aureus and B. subtilus). The results of this research can be useful in determining the best sampling date of this plant for pharmaceutical and antibacterial uses.

---

Demand for the production and consumption of fresh meat has led to the use of various methods to improve the quality characteristics and increase its shelf life. In this study, stinging nettle extract (SNE) in combination with epsilon (ɛ-PL) were used for the production of fresh, functional, and extended shelf life of beef fillets. After drying of stinging nettle leaves under favorable conditions, aqueous extraction was performed at concentrations of 3, 6 and 9% (w/v) of leaves. A solution of ɛ-PL at 0.5% (w/v) concentration was prepared and mixed with 3, 6 and 9% of SNE. Beef fillets (4 treatments) were prepared in 2×2×2 sizes and treated for 1 h at 4 ° C with a ratio of 1 to 1 (meat fillets to SNE). Distillation water was used to treat the control. Finally, beef fillets were packed in polyethylene bags and quality properties were performed at days 1, 3, 6, 9 and 12. During storage, pH, phenolic compounds, redness value (a) and sensory scores decreased significantly (P < 0.05), and in contrast to lipid oxidation, total volatile nitrogen, lightness (L) and yellowness (b) increased significantly (P < 0.05). It was found that the treatment of beef fillets using SNE (6%) in combination with ɛ-PL (0.5%) resulted in a significant reduction (P < 0.05) in the amount of lipid oxidation and total volatile nitrogen compounds of about 50% compared to the control sample. The color and sensory characteristics of processed beef fillets showed that SNE in combination with ɛ-PL could increase the sensory scores of the samples. Based on the results, SNE had synergistic effects with ɛ-PL in reducing lipid oxidation and total volatile nitrogen compounds, therefore it could be used to produce fresh and functional beef.

---

Surface pressure fluctuations beneath turbulent boundary layer on a flat plate have complex physical behavior and due to its importance in acoustic noise generation, extensive studies have been devoted to predicting or measuring the surface pressure behavior. In the present study to investigate the surface pressure fluctuations under zero pressure gradient, a flat plate with a chord length of 580 mm has been used. All experiments were carried out in a subsonic wind tunnel and at three free-stream velocities: 10, 15 and 20 m/s. In order to measure unsteady pressure fluctuations, a condenser microphone is used as a pressure transducer. Moreover, various parameters of turbulent boundary layer are measured to provide the input variables of semi-empirical models. A single constant temperature hot-wire anemometer has been used for boundary layer measurement. Surface pressure spectra has been measured at various velocities and their collapse on a single curve by normalizing with different variables of turbulence boundary layer is studied. The results show that the best collapses in low and middle frequencies can be obtained by using mixed variables. However, in high frequency range the pressure spectra collapses when it is normalized by inner layer scales. Finally, after ensuring the accuracy of surface pressure spectra results, the efficiency of semi-empirical models for predicting turbulent boundary layer wall pressure spectra is evaluated. The results show the effectiveness of the Goody’s semi-empirical model for prediction of surface pressure spectra by using turbulent boundary layer parameters.

---

In the present work, experimental and numerical results of the effects of different pressure curve on the thickness variation of sheet metal and distribution of radius and hoop strain for effective stress-strain curve have been presented. A series of experiments are carried out using a hydroforming apparatus by exerting different pressure curves including pendulous, steeped, saw and continuous. In each series, the effect of changes in pressure curve on thickness distribution was quantitatively measured. Different pressure curves such as continuous, stepped, and pendulous was produced in experiments. The ABACUS software was implemented to simulate the effect of changes in pressure curve. A good agreement between the experimental and numerical results was observed. The results show that stepped pressure produces more uniform distribution in sheet metal thickness. Mechanical behavior of sheet metal during plastic deformation phase under stepped pressure, produced satisfactory results, and using this type of pressure could control the effects of friction between the die surface and sheet metal specimen much better. Also, constant time duration of pressure pulses in stepped and pendulous curves leads to decreasing of maximum pressure needed for deformation of sheets.

---

Powdered activated carbon has high adsorption capacity with the remarkable nonpolar surface. The surface forces (van der Waal’s and London) create a stronger attraction between the carbon surface and impurities in comparison to present molecules in dilute molasses. The aim of the study was to adsorb types of impurities such as colorants, turbidity agents, phenolic compounds, anthocyanin and protein of dilute molasses (35% sugar beet dilute molasses) using powdered activated carbon at 4 levels (0.61, 0.78, 1.13, and 1.83 g 100g-1 dilute molasses) at pH 4.5. Further, Freundlich and Longmuir sorption isotherm models were evaluated to predict reduction of impurities. The results of equilibrium isotherms based on the coefficient of determination and adsorption capacity exhibited that the adsorption of impurities such as colorants (R² = 0.9605 and K_f = 5.0794), phenolic compounds (R² = 0.7605 and K_f = 0.9755) and protein (R² = 0.9679 and K_f = 1.9314) didn’t follow from Freundlich model. Turbidity agents and anthocyanin didn’t follow any of the studied models.

---

In this paper, the Navier-Stokes and Laplace equations are solved using the Finite Element Method (FEM) based on complex Fourier elements. The FEM is considered by two types of shape functions: Lagrange shape functions and new complex Fourier functions. The proposed interpolation functions are derived using enrichment of complex Fourier radial basis functions in the form of . The present functions have properties of Gaussian and real Fourier radial basis functions. These useful properties have provided the robustness of the proposed method. Also, these functions have the simultaneously functions field such as trigonometric, exponential, and polynomial; while the classic Lagrange functions satisfied only polynomial functions field. In other words, these features provide an improvement in the solution accuracy with number of elements which are equal or lower than the ones used by the classic finite element method.
Solving the Navier-Stokes and Laplace equations is the important challenge in the fluids mechanics problems. The most problems cannot be solved by the analytical methods. For this reason, the numerical methods are developed. Generally, the numerical methods are divided to two classes: the methods based on the mesh and meshless methods. In the first class, the computational domain are meshed and the governing equations are solved based them the finite element method, Finite Difference Method (FDM) and finite volume method (FVM) are placed in this category. While, in the second category methods, the computational domain is divided to moving particles. In these methods, there is no needed to any grid and the equations are solved on the particles. The smoothed particles hydrodynamic (SPH) method, Moving Particles Semi-implicit method and Discrete Least Squares Meshless method are in this class. The FEM is capable to solving the problems with complicated geometry. Also, the Neumann boundary conditions are applied properly.
    Generally, the numerical methods such as finite element and finite difference methods are based on the mesh for solving the equations. For obtaining the results with high accuracy, it is needed to have enough elements. On the other side, when the number of elements (or number of degrees of freedom) is enhanced, the CPU time and storage space are also increased. For this reason, in this paper, the complex Fourier shape functions have been developed, which using them, both the number of elements can be reduced and also the suitable results can be obtained.
In the present paper, at first, the governing equations and boundary conditions are expressed. Then, the FEM formulation and solution procedure are stated. Next, the complex Fourier shape functions and their enrichment process are described. Finally, three benchmark numerical examples are used in solving the Navier-Stokes and Laplace equations for the application of the proposed functions in the finite element method. These tests include Couette flow, flow of a viscous lubricant in a slider bearing and steady state heat transfer in rectangular region.  In order to show the efficiency and accuracy of the present method, the results of the proposed method are compared with the classic functions and also the analytical solutions. The results of this comparison indicate the high accuracy of the proposed method.

---

Chitosan based films have several disadvantages, such as poor mechanical properties and low moisture deterioration, which limits their use in food packaging. In this study, nanomaterials such as nanoclay (M) and nanosilver (Ag) were used to improve the properties of the film whilst applying electrical current during film drying. Nanocomposite films based on chitosan, were prepared by adding four levels 0, 1, 3 and 5% silver and clay, then heat and electricity with 0, 15, 30 and 60 Voltage were simultaneously applied to dry them, finally their characteristics like including WVP, O₂P, physical and mechanical properties, and microstructure were studied. The presence of nanoparticles in nanocomposite films increased the moisture, thickness, opacity, WVP, O₂P and improved mechanical properties, incomparison with pure chitosan film. On the other hand, the concentration of 3% in both treatments improve the permeability and mechanical properties of the 1 and 5% levels. The application of electrical current had no significant effect on moisture content, solubility and thickness. In contrast, the use of electric current with a voltage of 30, improved mechanical properties, turbidity and WVP and a voltage of 60, improved O₂P in nanocomposites. The images produced by the SEM show that the pure chitosan film has a rough surface and multiple gaps and the film surface of the nanoclay is relatively smooth and compact, which allows for increased tensile strength and inhibitory properties. The film containing nanosilver also had a more turbulent structure with a gap, turbidity and mechanical properties, and less inhibitory properties than nanoclay.

---

The purpose of clarification pomegranate juice by ultrafiltration process was its effect on bioactive compounds and degradation of bio-colorants during processing. For this aim, the effect of temperatures (20 and 30°C) and pressures (1.5, 2 and 2.5 bar) on anthocyanin, phenol, tannin and color indices were investigated. The results showed that the applied treatments significantly reduced anthocyanin in pomegranate juice. Treatments of 20°C-2 bar and 30°C-2 bar with 2.8 and 14.34% had the lowest and highest decrease in anthocyanin content, respectively. All treatments applied significantly reduced the total phenol content of pomegranate juice by 15-28-27%. Treatments of 20°C-2 bar and 30°C-2 bar with 6563.6 and 5696.9 mg/L had the highest and lowest phenols, respectively. The total tannin content for 20ºC and 30°C was 700.6 and 746.7 mg/L, respectively. The rate of reduction was between 39.34% for 1.5 bar-30°C treatment and 49.7% for 2.5 bar-20°C treatment. The total color density at 20°C and 30ºC was 1.09 and 1.17, respectively. Due to the rapid degradation of anthocyanins and tannins at high temperatures and generation of dark brown pigments, the total color density increased. The rate of tannin color reduction was between 39.34% for 1.5 bar-30°C treatment and 49.7% for 2.5-bar-20°C treatment. It was concluded that the effect of membrane process on tannin color reduction (45%) was more than anthocyanin color (23%). Regarding the browning index of permeation, the highest and lowest decreases equal to 34.45 and 19.88% were related to 2.5 bar-20°C and 2 bar-30°C, respectively.

---

In this study, extracts of mountain tea were obtained by maceration, supercritical fluid, ultrasound assisted, subcritical water and microwave. The highest extraction efficiency (22.55%) and total phenolic content (80.50 mg GA/g DM) was observed in extract obtained via ultrasound assisted extraction. Antioxidant activity of different concentrations of extracts was compared with 100 ppm TBHQ synthetic antioxidant and an increased in concentration of extract increased antioxidant activity. Type and percentage of wall materials (0, 50 and 100), the ratio of extracts to wall materials (0.1, 0.25 and 0.4 w/w), and sonication time (2, 4 and 6 min) as independent variable levels and encapsulation efficiency of phenolic compounds, particle size of nanocapsule and zeta potential were considered as a response to optimization of encapsulation conditions of the extract. An increase in sonication time resulted in increased encapsulation efficiency and decreased particle size of capsule. As the ratio of extract to wall materials increased, the encapsulation efficiency of extract increased and particle size decreased. Type of wall materials has effect on encapsulation efficacy, zeta potential, and particle size of capsule.  The optimum conditions for encapsulating of mountain tea extract were 6 min ultrasound; the ratio of extract to wall 0.4 and the amount of Arabic gum and alginate were 30.3% and 69.7% respectively. In optimum conditions, the encapsulation efficiency, Zeta potential and particle size were 57.43%, -52.1 mV and 82.06 nm. The amount of sedimentation and release of extract during the storage period was increasing. Nanocapsule has a smooth and interconnected structural that due to high encapsulation efficiency this nanocapsule can be added to food as an antioxidant compound.
 

---

In this research, the effect of condensation process (evaporation) on bioactive compounds and qualitative characteristics of thin syrup and thick syrup during beet harvest was investigated. The phenolic and anthocyanin properties of the dilute syrup and the quality characteristics investigated were brix, purity and color of the solution. For this purpose, from the beginning of October to the end of January 2019, samples were taken for thin syrup from the last stage of the purification process and for thick syrup from the last stage of the concentration process, and all the chemical tests related to measuring the characteristics The qualitative data of this study was based on ICUMSA reference book. In dilute syrup, the amount of bioactive compound anthocyanin was constant during the time of beet harvest, there was a significant difference in the amount of total phenol in the first and fourth months, but there was a significant difference in the amount of protein in the first, third and fourth months. He didn't have either. The highest brix of dilute syrup was 13.14% in the first and second months, and its degree of purity increased from the beginning to the end of the harvest season. The highest color of dilute syrup solution was observed in the third and fourth months of harvesting. Thick syrup had the highest Brix (53% on average) in the first and second months, and this syrup had a high soluble color at the time of harvesting, except for the second month. The results of this research show the accuracy of the filtration and evaporation processes in order to remove as much impurities as possible in the raw syrup extracted from sugar beet.

---

The aim of this research was to investigate the effect of basil, sage and chitosan edible coatings on the physicochemical properties of microwave-dried apple slices. In this study, apple fruit slices were coated with basil, sage and chitosan in three concentrations (0, 0.5 and 1%) and dried at different microwave powers (90, 180 and 360 W). The drying kinetics, color, texture and antioxidant activity of apple slices were investigated. The analysis of the data indicated that the drying of the apple slices happened only in the range of the descending speed period. These data were fitted with 7 different experimental models, among the models, the most suitable models for basil, sage and chitosan coatings were Midili, Approximation of diffusion and Verma, respectively. Midili was able to predict moisture content more accurately than other models. Also, the amount of brightness, adhesivenes, cohesiveness and antioxidant activity increased with the increase of coating concentration and microwave power, but the amount of redness, yellowness, browning, general color change and hardness decreased. In general, edible coating is one of the new methods that increases the shelf life and quality of the final product. Therefore, it is recommended to treat fruits using edible coatings to increase the appearance quality and improve the color at the end of the drying process.
 

---

Sunflower oil is one of the most important vegetable oils with high nutritional value, which is unfortunately sensitive to oxidation due to unsaturated fatty acids. In this study, sage leaf extract was obtained using ultrasound bath and ethanol solvent: water (70:30) at 35 ° C for 30 min at 35 KHz. The total phenolic content of extract was 31.12 mg GA/g. Antioxidant activity of 50, 100, 200 and 250 ppm of sage extract was measured by beta-carotene/linoleic acid bleaching assay and oxidative stability index. The results showed that increasing in the concentration of extract increased the antioxidant activity and oxidative stability index. Sage extract (250 ppm) was used for encapsualtion in the wall of qadomehshahri seed gum/whey protein isolate at 1: 0, 1: 1 and 0: 1 ratio. The particle size of the nanocapsule varied between 217.4 and 0.270 nm, and the nanocapsule prepared withqodomehshahrihad the largest size and the nanocapsule prepared with composition of gum and protein isolate had the smallest size. In order to intensify the oxidation process, sunflower oil without antioxidants, oils containing free extracts and TBHQ was placed in an oven at 60 ° C for 24 days. Peroxide, para-anisidine and Totox value of the samples were measured. The results showed that oil oxidation in samples containing encapsulated extract was less than the control, and oil containing free extract and TBHQ. At the end of storage time, the peroxide and paraanisidine value in oil samples containing encapsulated extract was less than oil containing synthetic TBHQ antioxidant and free extract. Also, among the walls used for encapsulating of sage extract, a composite wall made of qodomehshahri seed gum and whey protein isolate is the best coating for encapsulation the extract to increase the shelf life of sunflower oil.
 

---

 In order to reduce waste and increase the added value of marine products, this study utilized Caspian kutum fish scales as fish waste to extract gelatin. The effects of two methods—water-bath and ultrasound—on the physicochemical characteristics of the extracted gelatin were compared. Gelatin was extracted from Caspian kutum fish scales by water bath and ultrasound-assisted extraction at 60 °C for 1, 2, and 3 hours. The results showed that, in general, ultrasound caused a significant increase in the extraction yield, %protein, and %ash of the samples (P<0.05). The results of SDS-PAGE and FTIR analysis confirmed that ultrasound could affect the structure of gelatin proteins, and longer extraction times (2 and 3 hours) caused a decrease in the content of alpha chains compared to that of beta chains. The FTIR results showed amides A, B, I, II, III peaks, and these peaks became more intense in samples extracted by ultrasound and at higher extraction times. The melting point and gel strength of gelatin extracted by ultrasound were 26.67 °C and 269 g, respectively, which were significantly lower than those of the gelatin extracted by water bath (27.67°C and 307g, respectively) (P<0.05). The thermal analysis of gelatins showed that all samples had a broad endothermic peak between 35 °C and 200 °C related to water evaporation and an exothermic peak between 300 °C and 400 °C related to the thermal decomposition of gelatin.