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This study was conducted to evaluate the efficiency of Microwave-Assisted Vacuum Evaporation (MAVE) and Microwave-Assisted Evaporation (MAE) techniques for production of barberry juice concentrate in comparison to the conventional evaporation techniques. The barberry juice was concentrated by two different methods (indirect heating and the microwave evaporation under pressures of 100 and 30 kPa) to reach 60 °Brix. The results showed that the evaporation rates of MAVE and MAE methods were, respectively, 48.86 and 48.27% higher than indirect heating. The minimum changes in color parameters of barberry juice concentrate (L*, a*, b*, ΔE) were observed for vacuum-microwave evaporation. In addition, applying this method could better preserve anthocyanin content, antioxidant activity, and total phenol content of barberry juice compared to the conventional method. [ABSTRACT FROM AUTHOR]

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Cellular Automaton (CA) was applied, for the first time, to model mass transfer during the drying process. CA is a discrete model with powerful potential application for simulating complex systems. In this paper, a two-Dimensional (2D) model was applied to simulate drying process of banana slices. The system was designed for a grid with size of 30×90 square cells, four possible states, and von Neumann neighborhoods. The logical trends of the model results were examined by running program for different process conditions such as various temperatures, air relative humidity values, air flow velocities, and sample thicknesses. Validation of the model was performed by comparing estimated and experimental data of banana drying for three temperatures (60, 70, and 80°C). The model showed high accuracy for predicting moisture content (R2 values higher than 0.99). Notable accuracy based on simple rules to pattern the complexity of the system and flexibility indicated the superior application of cellular automaton for modeling food processes. [ABSTRACT FROM AUTHOR]

Since the microwave technology is well considered in food processing due to the speed and mechanism, in this study, cupcake was baked at different levels of MicroWave (MW) power (150, 300, 450 and 600W) and the effects of different kinds of operational time (3.5, 5, 8, 16 minutes) and power on physical properties (density, porosity, colour and height) and textural properties (crispness, hardness, cohesiveness, springiness, resilience, gumminess and chewiness) of cupcake were investigated. Results showed that the MW baking time to obtain desirable baking properties was affected by MW power. The obtained results showed that the total differences in colour from the reference batter (ΔE) and colour intensity increased with increasing of MW power. Moreover, the MW cupcake baked at a power of 600W had the least hardness, density, chewiness, gumminess values, the shortest baking time, and the highest values of cohesiveness, resilience, porosity, height, and browning index. Also, it had the highest cohesiveness, resilience, porosity, height and browning index, compared to the other powers. Therefore, the best operational power for desirable quality obtained during baking was 600W. [ABSTRACT FROM AUTHOR]

This study aimed to prepare zein/Montmorillonite (MMT) composite films by two methods: (1) An ultrasonic bath, and (2) A high power ultrasonic probe. Then, the structural, thermal, mechanical, and barrier properties of the obtained composites were evaluated. According to the X-Ray Diffraction (XRD) patterns, the composite films prepared by the first and second methods had microcomposite and exfoliated structures, respectively. Based on the results of the statistical analysis, the clay dispersion method and Montmorillonite (MMT) content significantly affected the mechanical, barrier, and thermal properties of the composite films. The results showed that mechanical and water vapor barrier properties of the nanocomposites were improved in the presence of small amounts (up to 3%) of MMT, while increased montmorillonite percentage in the microcomposite films weakened the mechanical, barrier, and thermal properties of these films. Therefore, the use of high power sonication is a suitable method for producing protein-based nanocomposites with an exfoliated structure. [ABSTRACT FROM AUTHOR]

The main functions of the packages are: Physical protection, barrier protection, convenience and information. Tendency to minim process food products, quality, safety and preventing of food born disease and strict requirements in relation to consumer health caused ways to use antimicrobial agents in food packaging and prevent the development of microorganism growth. Active packaging is one the methods of efficient packaging, that protect safety and quality of foods. The material of these packages is a suitable base for adding a wide range of different combinations such as antimicrobial agents to them. Pursuant to this, movie bionanocomposite films of Bitter vetch seed's protein with zinc oxide nanoparticles to produce an antimicrobial packages with %5 w/w of Bitter vetch protein isolate and 0.25, 1 and 2% zinc oxide nanoparticles. Glycerol was used as plasticizer. The mechanical and barrier properties of bionanocomposite films assessment and determined that the addition of zinc oxide nanoparticles as an antimicrobial agent to the protein film caused a sharp decrease of oxygen permeability through the films. The rate of water vapor permeability of bionanocomposite films decreased comparing with control film. The results indicated that lower levels concentrations of nanoparticles cause better functional properties of bionanocomposites films because of fewer particles coagulation. Effect of nanoparticles on the mechanical properties, tensile strength and modulus of elasticity were increased, but elongation of the film was reduced. [ABSTRACT FROM AUTHOR]

Semi-rigid aluminum containers are being used widely in food industries. They have wrinkle shaped walls for strengthening their physical structure. The objective of this study was to assess the effect of wrinkled parts on the heat transfer and temperature distribution of the containers by Computational Fluid Dynamics (CFD) analysis. Therefore, a precise designed geometry of the wrinkled walls container was compared to a straight one. The analysis was carried out based on the physical properties of a carrotorange soup. The velocity vectors showed a strong circulation towards the core. The Slowest Heating Zone (SHZ) locations were the same for wrinkled and simplified containers. Average temperature of the symmetric plane and the coldest point of SHZ showed less than 1% difference. The lethality imposed to the SHZ in the wrinkled wall container was about 0.4% more than the straight one. The simulation results revealed that wrinkled walls do not play an important role in increasing heat transfer and as a result, such geometries could be simplified while modeling. [ABSTRACT FROM AUTHOR]

In present study, dried pomegranate peel of three dominant Iranian varieties was extracted by soxhlet extraction (SE) method via four solvents. In this study Five anthocyanins were identified and quantified in the extracts by high performance liquid chromatography (HPLC) coupled with ultraviolet-visible (UV-Vis) spectrometric detector at wavelength of 517 nm according to their retention times and external standard method. According to the results extraction yield of Poost Siyahe Shirine Ardestan (PSSA) variety is more than other two varieties and extraction yield of ethanolic extracts is more than other solvents in p≤0.05. HPLC analysis was indicated pomegranate peel include of more mono glucoside anthocyanins than di glucoside anthocyanins also the most of anthocyanins particularly mono glucoside anthocyanins were detected in ethanolic extract obtained from dried peel of PSSA variety. [ABSTRACT FROM AUTHOR]

Pistachio nut (Pistacia vera L.) is one of the most delicious and nutritious nuts in the world. In order to increase the added value of the pistachio nuts, it is necessary to develop new products to meet consumer needs. This is the first paper on pistachio halva. The product was developed using pistachio paste (as main ingredient), mixture of sugar-glucose, egg white and citric acid. The effect of soapwort root extract (from saponaria officinalis) and Glycyrrhizin (from Glycyrrhiza glabra) as whitening and emulsifying agent in three levels (0.00, 0.10, and 0.15%) on the oil separation, consumer acceptance, and texture of pistachio halva was investigated. Sensory evaluation was carried out after 4 months storage at 20±2°C. There was a significant difference (P< 0.05) between samples with and without soapwort and glycyrrhizin. The oil separation (R= 0.595, P=0.001), from halva were moderately correlated to the hardness. The sensory texture of halva was negatively correlated to the hardness (R= -0.694, P= 0.000) and oil separation (R= -0.730, P= 0.000). The sensory color (R= 0.652, P= 0.000) of halva was moderately correlated to the a-value. It is recommended that mixture of 0.10% soapwort root extract and 0.10% commercial Glycyrrhizin be used for the pistachio halva production. Using combination of soapwort root extract and Glycyrrhizin in the formulation of pistachio halva prevents oil separation from the product and increases its consumer acceptance. Development of pistachio halva would potentially increase the food uses of nuts and introduce consumers with a healthier non-animal snack food. [ABSTRACT FROM AUTHOR]

This study was aimed at evaluating the flow behavior characteristics of yogurt enriched with fish oil (FO) microcapsules prepared by complex coacervation method. FO was microencapsulated in gelatin-acacia gum coacervates. Then, the microcapsules were dried, and yogurt was produced from the milk enriched with microcapsules powder. Rheological characteristics (as measured using a rotational viscometer) of yogurt were evaluated in the shear rate range of 0.262-7.86 s-1 at 6°C during 21 days of storage. Power Law model was used for calculation of consistency coefficient and flow behavior index of yogurt. As compared to the control, the enriched yogurt had higher apparent viscosity. Consistency coefficients of the enriched and the control yogurts were in the range of 24.42-28.82 and 15.31-17.76 Pa sn, respectively. Yogurt samples showed a non-Newtonian shear-thinning flow behavior. Addition of FO microcapsules to yogurt may be useful for improving its health-promoting effect and consistency. [ABSTRACT FROM AUTHOR]

In this study, a numerical model was developed to investigate the two-dimensional heat transfer in a homogenous finite cylinder to predict the local temperature and sterilizing value during caviar pasteurization. A fixed grid finite difference method was used in the solution of heat transfer equations according to Crank-Nicolson's scheme. The model was validated by comparison of the experimental temperature profiles during caviar pasteurization with the model predicted values (Correlation Coefficient> 0.99 and Root Mean Square Errors< 0.61°C). The cold spot location was at the radial center between the middle and top of the jar on the vertical axis. For caviar pasteurization, the required heating time for cold spot to reach the desired F-value ( F 82.2°C5.5°C = 0.19 min) was 128 minutes at 55°C and 37.63 minutes at 65°C. The results indicated that the developed model could be successfully applied to simulate the caviar thermal processing. [ABSTRACT FROM AUTHOR]

Unfavorable conditions in the production and storage of traditional breads, lead to a high decline in bread quality and thus severe damage and high economic losses. Hence, in this study Baked-Off Technology (BOT) and Modified Atmosphere Packaging (MAP) were used for increasing the shelf life of part-baked product. For this, part-baked Sangak bread was packaged in polyamide/polyethylene bags of 100 μm thickness with three compositions gas included %100 CO2, %50 CO2: %50 N2, %25 CO2: %75 N2 and air as a control and storage at 25° C for 21 days. During storage, quality and microbial features of product such as moisture, texture, total count and mold and yeast count was assessed at intervals of three days. The results showed moisture and texture of part-baked Sangak are not influenced by the atmosphere in the package. While the number of total microorganisms and also mold and yeasts are totally dependent on the amount of carbon dioxide used in the headspace. To increase the proportion of carbon dioxide, the growth rate of bacteria and fungi can be slow. In addition, in this study, significant effect of storage time on all of the qualitative and microbiological characteristics of part-baked Sangak was observed during storage. [ABSTRACT FROM AUTHOR]

Non- alcoholic malt drinks are popular in many countries including Muslim countries. In Iran, these drinks are prepared in a manner similar to beer, but without fermentation and are generally produced using barley malt. In this study, malt drinks with ratios of 0:100, 25:75, 50:50, 75:25 and 100:0 of barley to oat malts, the latter obtained under optimum conditions in terms of its enzymes activity, were produced and their physicochemical properties along with their storability were evaluated during six months of storage. The results showed that with increasing the proportion of oat malt in drinks, total solids, ash, acidity, reducing and total sugars increased. The results also indicated that by increasing the oat proportion, bitterness, color, turbidity and foam instability increased, while the amount of foam decreased. It was evident that the oat malt had positive effects on color and bitterness as compared with that of barley, and had more antioxidant compounds. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the effect of fermentation, hydrothermal treatment, soda (Na2CO3), and table salt (NaCl) addition on the extent of phytase activity and phytate degradation in three Iranian wheat cultivars, namely, Mahdavi, Ghods, and Roshan. The samples were milled to three different extraction rates, i.e. whole, 85%, and 75% flours and three kinds of leavening procedure (fermented, soda, and control), and four NaCl percentages (0.0, 0.5, 1.0, 1.5%) were used for preparing dough in three replications. To evaluate the effect of heat treatment on phytic acid breakdown, baking was also done. The results indicated that among the wheat varieties, Mahdavi had the highest level of phytase activity and phytic acid content followed by Ghods and Roshan; in which, most of the phytate was concentrated in bran fractions. Fermentation (1% yeast at 37°C for 3 hours), hydrothermal treatment (pH 4.8 at 55°C for 12 hours) and salt addition (0 to 1.5%) to the dough samples resulted in an increased phytase activity, whereas soda addition (1%) decreased the enzyme activity. Heat treatment reduced phytic acid content significantly. [ABSTRACT FROM AUTHOR]