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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]

Background: Literature review shows that there are not sufficient data about polyphenolic compounds of peel of Iranian pomegranate. So, this work was mainly undertaken to determine phenolic compounds and antioxidant activity of dried peel of Iranian pomegranate. Methods: Pomegranate fruits were obtained from mature fruits grown in Saveh, Iran and the Pomegranate Peel (PP) were dried with three different methods. Powders of PP were extracted with four different solvents, using a soxhlet apparatus. The compounds of PP extracts were analyzed by High Performance Liquid Chromatography (HPLC). Then, yield percentage and Radical Scavenging Activity (RSA) were determined. Statistical analysis was performed using the SAS 9.1 software. Results: Different ranges of tannic acids, testosterone and α-estradiol, estriol, estrone, cyanidin 3-glucoside, cyanidin3,5-diglucoside, pelargonidin 3-glucoside, pelargonidin 3,5diglucoside, and delphinidin 3-glucoside were identified. Both the highest yield percentage (18.820±0.661) as well as the highest RSA percentage (63.862±0.376) were obtained from the ethanol showing significant (p<0.05) difference with the other solvents. Drying method of PP showed no significant (p>0.05) relationship with yield of extraction and also antioxidant activity of the PP extracts. Conclusion: HPLC analysis identified some various phenolic compounds in Iranian PP extract showing considerable antioxidant activities. Although drying method showed no relation with yield of extraction and also antioxidant activity of the PP extracts, but type of solvent was effective on yield of extraction and type of extracted compounds of PP. [ABSTRACT FROM AUTHOR]

Microwave assisted fluidized bed drying is a novel drying technique which reduces drying time and yields higher quality products. In this study the effect of this method on color changes of whole and cut hazelnut kernels was investigated. The parameters of color and resulting total color change, chroma, Hue angle and browning index were also calculated during drying in three temperatures (40, 50 and 60°C) and microwave power levels (0, 450 and 900W). Comparison was made to investigate the effect of drying condition on browning of hazelnut surface and internal cavity. The zero and first order kinetic models were also fitted to whole and cut kernel color parameters. The results showed similar behavior in color parameters of whole and cut kernels. L value and Hue angle decreased with increasing drying time, drying air temperature and microwave power but a, b, ΔE, chroma and browning index increased. L and b values of whole kernels were higher than cut kernels but the a value was lower. Zero-order model was selected as the best model for predicting a, b and ΔE while first order model best described the kinetics of color changes of L, chroma, Hue angle and browning index. [ABSTRACT FROM AUTHOR]

The aim of this work was to optimize the spray drying conditions for the production of ice cream mix powder. A lab-scale spray dryer was employed for the spray drying process, the mix of salep and k-carrageenan was used as stabilizer and black mulberry juice added to ice creams as a natural flavor. Response Surface Methodology (RSM) was performed to examine the influence of inlet air temperature (120, 140, and 160°C), feed flow rate (5, 10, and 15%) and black mulberry concentration (15, 30, and 45%) on drying yield and total anthocyanin content of powders, overrun and melting rate of ice creams prepared from the reconstituted powders. Scanning electron microscope was used for monitoring the structure of the powders. The following optimum process conditions were determined: inlet air temperature of 138 °C, feed flow rate of 8% and juice concentration of 35%. These parameters led to the process yield, total anthocyanin content, overrun and melting rate of 76.14%, 54.11 mg L-1, 74.50%, and 1.52 g min-1, respectively. [ABSTRACT FROM AUTHOR]

The unique properties of camel milk, qualify this product to be used as a nutraceutical. In this study, functional synbiotic yogurt made from camel milk has been investigated in three levels of fat (0, 2.5 and 5% (w/v)). Probiotic bacteria (Streptococcus thermophilus, Lactobacilus delbrueckii and ssp. bulgaricus.) and β-glucan (prebiotic agent) were added in three levels of concentration (0.5, 1 and 1.5% (v/v)) and (0, 1 and 2% (w/v)), respectively. The physicochemical properties of the product and viability of probiotic bacteria were measured on the 0, 7th and 14th days. Beta-glucan, fat and storage time had significantly (P< 0.05) increasing effects on viscosity, Water-Holding Capacity (WHC) and the viability of probiotic bacteria. These parameters caused decrease in syneresis and pH of yogurt. It was concluded that the addition of oat β-glucan to camel milk to make functional synbiotic yogurt could result in a product of acceptable physicochemical properties. [ABSTRACT FROM AUTHOR]

Salep composite films containing 0±30% (w/w) oleic acid or stearic acid - were prepared through emulsification and their physical, mechanical, and barrier properties were evaluated and compared. Emulsified films were softer than pure films. Addition of the fatty acids to salep films significantly improved the WVP (P<0.05), but lowered the tensile strength. Stearic acid was more effective than oleic acid in reducing the WVP, but films with oleic acid showed better mechanical properties overall than those with stearic acid. Also the presence of fatty acids decreased solubility in water and caused the films to become opaque. On the other, fatty acids showed different effects on the elongation at break. This work showed that when taking all the studied variables into account, films formulated with oleic acid were found most suitable for various food applications. [ABSTRACT FROM AUTHOR]

The main target of this research is drying raspberries in a Microwave assisted fluidized bed dryer. In order to evaluate and predict the quality properties of this fruit, Response Surface Methodology (RSM) was used. In this research, the effects of five variables: power of microwave (0, 300 and 600 W), temperature (55, 70 and 85 C), air flow rate (15, 20 and 25 m/s), starting time of microwave input (from the moment when the moisture content decreased until 334, 400 and 466 g water per 100 g dry matter) and amount of material (50, 100 and 150 g) on the rehydration capacity and loss of anthocyanins content were studied. Experiments were designed according to Central Composite Rotatable Design with these five factors each at three different levels, including central and axial points. With respect to the dependent variables, both linear and quadratic effects of all of the five independent variables on Rehydration Capacity and loss of anthocyanins content were found to be significant. For each response, second order polynomial models were developed using multiple linear regression analysis. Analysis of variance (ANOVA) was performed to check the adequacy and accuracy of the fitted models. According to our results, the optimal point for both characteristics were as follows: microwave power 600 W, temperature 74 , the air flow rate 3/22 meters per second and 53 grams of the substance, starting from the moment the microwave 466 percent moisture content was reduced. Model to predict the dependent variables with empirical results obtained were very close. [ABSTRACT FROM AUTHOR]

In this study, the effects of some processing parameters on drying yield, moisture content, solubility and bulk density of spray dried cornelian cherry (Cournus mas L.) juice powders were investigated. A pilot-scale spray dryer was employed for the spray drying process and maltodextrin and gum Arabic were used as carrier agent. Experimental design involved the use of Box-behnken design and response surface statistical method. Independent variables were inlet air temperature (110, 140, and 170 C), concentration of drying aids (0, 7.5, and 15 %) and feed flow rate (6, 9, and 12 %). Results show that increasing in concentration of drying aids, increases drying yield and the solubility and reduces the moisture content and bulk density of powder; also increasing in inlet air temperature, increases drying yield and reduce solubility, moisture content and bulk density of powder. Optimization carried out using response surface methodology and optimum conditions were inlet air temperature of 140 oC, maltodextrin concentration of 7% and feed flow rate of 9%. [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]

Among the different classes of physical properties of foods, color is considered the most important visual attribute in quality perception. Consumers tend to associate color with quality due to its good correlation with physical, chemical and sensorial evaluations of food quality. This study used an inexpensive method to predict sweet cherries color parameters by combining image processing and artificial neural network (ANN) techniques. The color measuring technique consisted of a CCD camera for image acquisition, MATLAB software for image analysis, and ANN for modeling. To demonstrate the usefulness of this technique, changes of cherry color during ripening were studied. After designing, training, and generalizing several ANNs using Levenberg- Marquardt algorithm, a network with 7-14-11-3 architecture showed the best correlation (R2= 0.9999) for L*, a* and b* values from Chroma meter and the machine vision system. L* and b* parameters decreased during ripening of cherries and a* parameter increased at first and then decreased. Evaluation of L*, a* and b* values showed the possibility of reliable use of this system for determination of absolute color values of foodstuffs with a much lower cost in comparison with Chroma meter. [ABSTRACT FROM AUTHOR]

In this study, the effect of addition of three different levels of microbial lipase (0, 4, and 8.0 g lipase in 100 kg milk) was investigated on the physiochemical properties, free fatty acids, textural properties, and microstructure of Lighvan cheese during ripening. The addition of lipase did not significantly affect pH, acidity, moisture, and salt content of Lighvan cheese, but increased its free fatty acid content considerably. It also increased hardness and decreased the brittleness of Lighvan cheese in all stages of ripening. The number and the mean diameter of fat globules, which were entrapped in casein network, were affected by all levels of the added lipase. Following the addition of lipase to Lighvan cheese and after 90 days of ripening, individual fat globules or their aggregates totally disappeared and some fingerprints of fat were observed. Disappearance of fat globules along with increase in protein matrix junctions leads to uniform structure of casein consisting voids which are produced from fermentation. [ABSTRACT FROM AUTHOR]

Interaction of menthol with polyethylene terephthalate bottles during storage time was tested at three different temperatures. Menthol is a mint flavor agent added to yogurt drinks in Iran and is considered as a factor affecting consumer acceptance. Absorption of menthol to packaging material could cause a loss of quality in the final product due to diminished flavor intensity. Tests were done on the effects of environmental conditions (storage for three months at temperatures of 4, 25, and 45°C) on flavor stability of yogurt drink samples. Absorbed flavor was extracted from PET bottles after the specified time periods and quantified using gas chromatography coupled with FID detector. Then, the diffusion coefficient of menthol into PET bottles (Dp) was determined using concentrations of absorbed menthol. Results showed different absorption levels under various conditions. After 90 days, the absorption quantities at 4, 25, and 45°C were 38.21, 186.66 and 700.50 ng g-1 of PET bottle, respectively. It was concluded that amounts of menthol absorption into PET bottles increased with storage time and higher temperature. Elevation of storage temperature resulted in significant increase in diffusion coefficient of menthol in PET bottle. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) was used for decolorization of an industrial Iranian date syrup. Experimental results were obtained by using two different concentrations of the date syrup (40 and 50 °Brix) and two different membrane pore sizes (15-20 and 30-50 kDa molecular weight cut-off values) under different trans-membrane pressures (TMP: 40, 70, 110 and 150 psi). The membrane with a pore size of 15-20 kDa resulted in average decolorization of 56% and turbidity reduction of 90%. Increasing TMP from 40 to 150 psi led to the decolorization and turbidity reduction of 48 and 82%, respectively. When the concentration of date syrup was increased from 40 to 50 °Brix, the levels of decolorization and turbidity reductions reached 47 and 78%, respectively. Reduction in the turbidity of date syrup was correlated with increases in the lightness (L*) and yellowness (b*), while the redness (a*) was decreased. Changes in the fructose and glucose levels due to the UF operation were much less than those of color and turbidity. [ABSTRACT FROM AUTHOR]

Glycyrrhiza glabra roots harvested at two different times (T1: 20 October 2010 and T2: 20 January 2010) were analyzed for their chemical composition, and then antioxidant activity and antibacterial effect of ethanolic root extract against some pathogenic bacteria were evaluated. Higher amounts of moisture were detected in T1 licorice root, whereas higher levels of sugar, protein, ash and phenolic compounds were determined in T2 licorice root. The antioxidant activity was assessed by DPPH, reducing power and total antioxidant capacity assay and T2 licorice root was found to possess higher antioxidant activity. Antimicrobial activity was estimated using a microdilution technique (ELISA) against some human pathogenic bacteria. The following bacteria were tested: Salmonella entritidis (gr-), Escherichia coli (gr-), Bacillus cereus (gr+) and Staphylococcus aureus (gr+). It exhibited antimicrobial activity against both tested Gram-positive and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effects of osmotic process with or without ultrasound on solid gain (SG) and water loss (WL) of cranberries. Response surface methodology was used to model and determine the optimum processing conditions for WL and SG during osmotic dehydration of samples. Sucrose (40-60%) and salt (0-8%) concentrations, temperature (30-50 °C) and frequency of ultrasound (0-130 kHz) were the factors investigated with respect to WL and SG. Experiments were designed according to a second-order Central Composite Design (CCD) in the form of a Face-Centered Cube (FCC) with these four factors, each at three different levels, including central and axial points. All experiments were conducted in triplicate. Experiments were conducted in a shaker with constant 150 rpm agitation and solution to sample mass ratio of 10/1 (w/w). Analysis of variance (ANOVA) was performed to check the adequacy and accuracy of the fitted models. Statistical analysis of results showed that the linear terms of all the process variables had a significant effect on WL. Except for temperature, all other parameters had a significant effect on SG. Optimum operating conditions were found to be sucrose concentration of 50.1%, salt concentration of 8%, temperature of 50 °C and ultrasound frequency of 130 kHz. [ABSTRACT FROM AUTHOR]

Hamburgers with high nutrient supply and a loosely-packed structure present favourable conditions for microbial growth. In this study, the chemical composition and antimicrobial activity of the essential oil of Zataria multiflora and its potential application as a natural preservative in reducing the indigenous microbial population of hamburgers were investigated. Carvacrol, thymol and linalool were found to be the most abundant constituents of the essential oil using GC-MS analysis. The essential oil exhibited strong antibacterial activity against Gram-positive and Gram-negative bacteria. Addition of Z. multiflora essential oil in concentrations higher than MIC values influenced the microbial population of hamburgers stored at 25°C, 4°C and –12°C. The significant results of this study are our observations that the use of Z. multiflora essential oil at 0.05% v/w increases the time needed for the natural microflora of hamburgers to reach concentrations able to produce a perceivable spoilage at refrigerator and room temperatures without any inverse effect on their sensory attributes. Freezing of essential oil-treated hamburgers may also reduce the risk of diseases associated with consumption of under-cooked hamburgers through significant microbial reduction by more than 3 log. [ABSTRACT FROM PUBLISHER]

The effect of carboxymethyl cellulose (CMC) coating on the mass exchanges during the osmotic dehydration of apples and its effect on the quality of final product were studied. Coating semi-rings of apple with CMC solution (1%) was found to prevent solute uptake and to reduce salt diffusion coefficient from 4.35 × 10-10 m²/s to 2.86 × 10-10 m²/s. However, coating did not significantly affect the diffusivity of water. The effective diffusivity of salt and consequently solids gain were found to be depended on the concentration of CMC solution in the range of 0-1%. Increasing the concentration of CMC further from 1% had no effect on the mass exchanges during the osmotic process. Maximum performance ratio, defined as water loss/solids gain, and the lowest solids diffusion was observed for coated samples (with 1% CMC solution) treated with an osmotic solution containing glucose syrup (50%) and NaCl (2%). [ABSTRACT FROM AUTHOR]