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Due to the increasing use of biopolymers in food formulations, introducing new hydrocolloid sources has become particularly important. Numerous researches have been done on aqueous extraction or new extraction methods such as extraction with microwave pretreatment, but in most cases, the engineering part of these processes has been neglected. In this study, the main purpose was to investigate the mass transfer in the process of microwave -assisted extraction of galactomannan from two plant seeds using a new method known as inverse numerical method. To achieve this goal, the concentration of galactomannan extracted from both plant seeds was obtained against time and the experimental data and the data predicted by the software (based on the simulation) were compared which indicated proper convergence between these data. Effective parameters in mass transfer including dispersion coefficient (E), diffusion coefficient (D) and total mass transfer coefficient (kc) were in the range of 1.12 – 1.63×10-12, 2.30 – 3.28×10-8 and 1.54 – 2.25×10-7 m²/s for fenugreek galactomannan and 1.27 – 1.76×10-12, 2.55 – 3.52×10-8 and 1.85 – 2.30×10-7 m²/s for Gleditsia caspica galactomannan. The difference between the values obtained for the two galactomannans could be attributed to the seed type, hardness or softness of the seed wall and characteristics of the target component. According to the obtained results, inverse numerical method could be introduced as an acceptable and effective method for modeling of the extraction process of both galactomannans. [ABSTRACT FROM AUTHOR]

Extraction of hydrocolloids from plant seeds is important due to the increased consumption of these compounds in the formulation of food products. Ultrasound -assisted extraction has become very popular due to its many advantages, one of the most important of which is to increase the extraction efficiency of the biopolymers. The aim of this research was to use inverse numerical method to estimate the effective parameters in mass transfer related to the ultrasound -assisted extraction of galactomannan form two plant seeds including fenugreek and Gleditsia caspica. To achieve this goal, the concentration of galactomannan extracted from both plant seeds was obtained against time and the experimental data and the data predicted by the software (based on the simulation) were compared which had proper convergence. Effective parameters in mass transfer including dispersion coefficient (E), diffusion coefficient (D) and total mass transfer coefficient (kc) were in the range of 1.21 – 1.52×10-12, 2.39 – 3.05×10-8 and 1.18 – 1.85×10-7 m²/s for fenugreek galactomannan and 1.31 – 1.54×10-12, 2.63 – 3.11×10-8 and 1.46 – 1.95×10-7 m²/s for Gleditsia caspica galactomannan. The difference between the values obtained for the two galactomannans could be attributed to the seed type, hardness or softness of the seed wall and characteristics of the target component. According to the obtained results, inverse numerical method could be introduced as an acceptable and effective method for modeling of the extraction process of both galactomannans. [ABSTRACT FROM AUTHOR]

Deep frying is one of the most common methods method of fast food preparation that provides the desired sensory properties in the food. The rate of oil absorption is affected by various factors such as processing conditions (temperature and time), pre-treatments, physico chemical properties of the raw material and chemical composition of oil.. The purpose of this study was to investigate the ultrasound and blanching pre-treatments effect on the physical and thermodynamic quality of fried carrots under deep frying conditions. In this study, moisture and oil content, bulk density and effective moisture diffusion coefficient were investigated. More over the rate of shrinkage was modeled by the neural network. The results showed that the use of combination of ultrasound and blanching pre-treatments reduced shrinkage, oil absorption and increased apparent density and effective emission factor of moisture content at 160 ° C, 180 ° C respectively. Moreover the modeling of neural network shrinkage showed a good correlation and overlap between the values predicted by the network versus actual values. [ABSTRACT FROM AUTHOR]

Drying foods, such as freezing methods and hot air, are not ideal and reduces the nutritional value and is also expensive and is used only for high value food. In this research, drying with supercritical fluid of carbon dioxide was investigated to remove moisture from the figs. In the drying process with supercritical fluid, the structure of food products is maintained during drying. The design of the experiment was carried out in a factorial arrangement using Design Expert software and analysis variance table to determine the effect of three pressure parameters, temperature, and time to measure the removal rate of moisture. The calculated factorial model was meaningful and able to select the best drying parameters. In optimum conditions, the highest yield (78.109%) with the desirability of 0.992 at 20 MPa, 60 °C and 120 minutes duration. The results showed that the drying of figs during the whole drying period is carried out at the downstream stage, which indicates that the drying of these materials, the internal moisture control, controls the rate of drying and mass transfer. In this study, by solving the second Fick's law and in the range of pressure and temperature tested, with the assumption of the spherical of the fig using the Crank equation, the amount of moisture diffusion coefficient between 4.51× 10-10 and 0.18 × 10-10 m2/s were obtained. The fig's drying rate was also calculated. Increasing temperature and pressure caused to increase the drying rate. [ABSTRACT FROM AUTHOR]

Simulation of water and salt transfer in soil is very effective in managing optimal water and fertilizer use in the field. In this study, the HYDRUS-1D model was used to simulate the transfer of water and bromide in a laboratory column of soil with clay loam texture. Soil hydraulic parameters (including air entry point) α, (saturated hydraulic conductivity) ks, (residual moisture content) θr (saturation moisture content) θs, (pore and particle joint parameter) l (parameter of moisture curve shape) n through measurement and using Retc software was obtained Solubility transfer parameters including difiusion coefficient and actual velocity were estimated using soil hydraulic parameters and bromide concentration data by reverse modeling method. According to the target coefficients, the sensitivity analysis of the physical model was performed .The results showed that the correlation coefficient of observation and simulation bromide concentration in optimal mode was 0.84%. accordingly, the diffusion coefficient was estimated to be 4.9 cm. based on the results of the sensitivity analysis, the saturation hydraulic conductivity had the greatest effect on the variation of this parameter, so that the amount sensitivity coefficient of this parameter was 2.64 The RMSE coefficient with a value of 0.04 was the lowest and ME coefficient with the value of -0.0001 had the most parameter variations. [ABSTRACT FROM AUTHOR]