JOURNAL OF FOOD RESEARCH (UNIVERSITY OF TABRIZ)
Year:2019 | Volume:29 | Issue:1|Papers Count:14

Introduction: Films manufactured by nano materials, biopolymers or so-called biopolymer nanocomposites exhibit desirable functional properties. Nowadays, various polysaccharides, such as cellulose, pectin, starch, marine algae and gum, are used in film production. Carrageenan is one of the natural polysaccharides that have been extensively studied in the field of the production of foods and protective coatings against drying, light and oxygen (Rhim & Wang 2014). One of the existing methods for producing active food packaging is the addition of active ingredients, including antimicrobial and antioxidant agents to packaging film (De Azeredo 2009). Among the extracts of various herbs, Peganum Harmala seed extract is one of the compounds with significant antimicrobial effect (Ghorbanpour and Jahedi, 1394). Peganum Harmala extract contains flavonoids and alkaloids antimicrobial agents (Diba et al., 2009). Among different extraction methods, ultrasound assisted extraction is a cheap, simple and effective method. Increasing the extraction efficiency and speed are the main important advantages of this extraction method (Chemat et al., 2012). Moreover, less temperature is required for extraction, in which causes less damage to heat-sensitive compounds. The aim of this study was to prepare carrageenan/nanoclay/glycerol films containing Peganum Harmala extracts prepared with ultrasound assisted extraction and investigating the physical, mechanical and antimicrobial properties of the film. Material and methods: For the preparation of extracts, 10 g of dried Peganum Harmala seed was weighed and blended with 90 ml ethanol. The solution was sonicated at 400 W for 10 min (7 seconds on and 3 seconds off) at room temperature, using an ultrasonic probe. An ice bath was used to prevent evaporation of the solvent. After the sonication, the extraction was filtered with a filter paper and stored at 4° C in dark glass vials for further use. Carrageenan based films were fabricated by the solution casting method. Firstly, 3 w/w% of nanoclay (based on Carrageenan dry weight) was added to 100 ml deionized water and vigorously stirred for 24 h at ambient temperature. Then, the nanoclay solution was sonicated using 100 W ultrasonic probes (7 seconds on and 3 seconds off) for 10 min. Then, 2 g carrageenan was added to the nanoclay dispersions and stirred at 82° C for 20 min. Finally, 1, 2 and 3 v/v% (based on solution volume) of the extract were incorporated into the film forming solution and stirred until a homogeneous mixture was obtained. The final mixture was cooled down to 65° C and 30 ml of film solution was cast onto polystyrene Petri dishes with 8 cm in diameter. All film samples were dried in an oven at 25 ° C for 24 h. Eventually, the dried films were stored in plastic bags before conducting the tests. Then, the effect of incorporation of the extract on the carrageenan film morphology, thermal stability, mechanical, optical, barrier and antibacterial properties were investigated. Results and discussion: The purpose of this study was to prepare carrageenan biopolymer-based antimicrobial films for active food packaging and environmental pollution reduction caused by synthetic packaging material accumulation. Carrageenan nanocomposite films containing 3% nanoclay (montmorillonite), glycerol and three concentrations of 1, 2 and 3% of the Peganum Harmala extract were prepared by casting method and their physical, mechanical and antimicrobial properties were investigated against E. coli and S. aureus bacteria. To investigate the variations resulting from adding Peganum Harmala extract to carrageenan/nanoclay nanocomposite films, scanning electron microscopy, thermogravimetric analysis, UV-Vis spectroscopy, FT-IR analysis were performed along the Fourier transformation of the films. The scanning electron microscope images from carrageenan/glycerol/nanoclay films with and without extracts showed a surface containing nanoclay, which were dispersed throughout the film. UV-Vis spectrometry showed that ultraviolet light and visible light of carrageenan/nanoclay/glycerol film was reduced by adding Peganum Harmala extract. This reduction in the sample containing 3% extract under ultraviolet light has been 2. 6-0. 3% and that of the visible light was 17. 7-9. 2%. According to a thermogravimetric analysis, adding Peganum Harmala extract to carrageenan film did not have any obvious effect on the thermal stability of the film. Tensile strength and lengthening of carrageenan/nanoclay/glycerol film without extract were 15. 9 MPa and 15. 0 mm. The results of the tensile test showed that the Peganum Harmala extract in a polymer-based carrageenan/nanoclay/glycerol film increased tensile strength by 2 times and lengthening 3 times greater than carrageenan/nanoclay/glycerol film without the extract. Finally, according to antimicrobial tests, the Peganum Harmala extract is antimicrobial materials suitable for producing films and biodegradable coatings for different food packaging. Conclusion: The UV-Vis spectroscopy showed that the addition of the Peganum Harmala extract to the carrageenan/nanoclay/glycerol film reduced its ultraviolet and visible light transmission. Based on thermogravimetric analysis, the addition of extract to carrageenan films did not have any significant effect on the thermal stability of the film, but the binding between the functional groups of component of extract, glycerol and carrageenan polymer increased the thermal degradation temperature of the Glycerol. The results of the tensile test indicate that the presence of extracts in the carrageenan film increases its tensile strength compared to the extract-free carrageenan film. According to antibacterial test results, the films containing the extract had antimicrobial activity. By increasing the extract content, the antibacterial activity of film increased.

Introduction: Between all the vitamins, ascorbic acid is destroyed with oxidation process, as well as in the extracts, juices and foods this vitamin is oxidized when exposed to air. The amount of oxidation is greatly accelerated by heating and alkali materials. Concentrate is a form of fruits that most of its main constituents or solvents are eliminated. Usually, by concentrating the juice in a solution or suspension and turning it into powder or extract, the concentrate is formed. The advantage of concentrate production is that by eliminating water, the weight of the food is reduced, and therefore its transportation is easier and less costly. Apples concentrate has always been a concern for juice and concentrate producers. Apple is quite economical due to lower prices and good brix. On the other hand, apple concentrate is used as the base for all types of beverages and juices in factories. It is also used in the production of apple vinegar. Considering the large volume of production of apple concentrate in industrial units, its quality is decreased over a period of time (between one and three months) depending on the conditions of production. In this research, it has been determined that L-ascorbic acid (vitamin C) can improve the quality and maintance of apple concentrate. Material and methods: L-Ascorbic acid (made in China), gelatin and Bentonite (Iran Barite Co. ) were used. Apple concentrate was carried out in the classic method (using filter materials and vacuum filters) at Azarakam Urmia Co. Perlites were provided from Zomorrod puyesh Urmia Co. Amylase and pectinase enzymes were used with the DSM mark. To control the turbidity of apple concentrate samples, a turbidometer instrument (H2A-N2100 HACH Co., United States) was used by. The DR2800 spectrophotometer (HACH Co., United States) was used to check the color and clarity of apple concentrates. The color of apple concentrates samples was measured by spectrophotometer at a wavelength of 440 nm. To do this, the apparatus was first calibrated with distilled water at 100, and then the apple concentrate (filtered with filter paper) was transported to the cell and the absorbance amount was recorded. The clarity of apple concentrates samples was measured by spectrophotometer at a wavelength of 640 nm. To do this, the apparatus was first calibrated with distilled water at 100, and then the apple concentrate was transported to the cell and the transmittance amount was recorded. The turbidity of apple concentrates samples was measured by the turbidometer instrument. To do this, the apparatus was first calibrated with distilled water at 100, and then the apple concentrate was transferred to the instrument cell and the turbidity amount was recorded. Results and discussion: Apple concentrates quality (clarity and color enhancement and turbidity decrease) was improved by flocculation and precipitation of concentrate by adding of 1-bentonite-gelatin mix, and 2-bentonite-gelatin-L-ascorbic acid mix. The mix solution of bentonite, gelatin, and L-ascorbic acid was added to apple concentrate in the four separated stages including; 1: to the mash enzyme tank, 2: to the crude apple juice, 3-to the fining tank (in single-stage), and 4-to the fining tank (in two-stage). The ratio of bentonite, gelatin, and L-ascorbic acid in the mix solution was optimized by experimental analysis. The quality of treated apple concentrates by bentonite, gelatin, and the L-ascorbic acid mix was analyzed by spectrophotometer and turbidimeter. The results showed that the samples treated with bentonite-gelatin-L-ascorbic acid mix had higher quality character than samples treated with the bentonite-gelatin mix, so L-ascorbic acid had a significant effect on the apple concentrate quality. Also, the results showed that adding of bentonite-gelatin-L-ascorbic acid mix to the samples in the fining tank (in single-stage) improved apple concentrate than other three stages. According to the results adding of bentonite-gelatin-L-ascorbic acid mix to the samples cause to stable quality of apple concentrate for 90 days. Conclusion: The results showed that the addition of ascorbic acid to apple juice before pasteurization due to the short duration of production in the production process and the decrease of ascorbic acid activity due to pasteurization had no significant effect on the apple concentrate, but adding the ascorbic acid in the pasteurized juice created a significant effect in all product quality parameters, which include: shortening the filtration time, shorter drainage time and lower consumption of perlite.

Introduction: Food products made from cereals and pseudo cereals have been known for their remarkable potential in food and beverage industry. Cereal and cereal-based beverages like those obtained from oat, rice, and soy have been gaining popularity for their specific health benefits. Recently, many researchers have been keen towards exploring underutilized grains and pseudocereals for their health potential and their future in the food and beverage industry. Quiuoa (Chenopodium quinoa Willd. ) is a pseudocereal which is traditionally cultivated in the Andean region since thousands of years. Commonly, quinoa grain and its flour are used for human consumption and animal feeding. The edible seeds of quinoa are small, round or flat. Seed colors can range from white to grey and black, or can be yellow and red. Quinoa has a very elevated genetic variability which makes possible to select, adapt and breed cultivars for a wide range of environmental conditions. Quinoa seed contains a considerable amount of fiber and mineralssuch as calcium and iron. It is also rich in antioxidants such as polyphenols. Moreover, quinoa is considered gluten-free and, therefore, suitable for celiac patients as well as people who have wheat allergy. The quinoa seed proteins are rich in amino acids including lysine, threonine and methionine that are deficient in cereals. The seed is used to make different food products including breads, biscuits, cookies, crepes, muffins, pancakes, and tortillas. The year 2013 was declared as “ International Year of the Quinoa” by the United Nations Food and Agriculture Organization in recognition of the indigenous peoples of the Andes, recognizing the high value of this pseudocereal crop. So, in the present study, we aimed to prepare quinoa-based gluten-free beverage contain honey and floral water of mint, and also evaluate the quality and sensory charactreistics after fermentation process (with selected probiotic bacteria) during 14 days storage at 4 ° C. Material and methods: Whole quinoa seed was purchased from Nathure Earthly Choice Co. The probiotic microorganisms used in the current study were Lactobacillus plantaru (PTCC 1058) and Lactobacillus acidophilus (PTTC 1643) which was grown on MRS broth for 18 h at 37 ° C with shaking (180 rpm) to reach log phase. The quinoa-based gluten-free functional fermented beverage was produced using Lactobacillus plantarum and Lactobacillus acidophilus in equal ratio, 50: 50 with addition of 5% (w/v) honey as natural sweetener and mint floral water at four levels of 0, 1, 2 and 3% (v/v). Antibacterial properties evaluation of mint floral water was done by well diffusion method, before addition to beverages. The sensory characteristics (taste, color, aroma, after taste and overall acceptability), total phenolic content (TPC), antioxidant activity (DPPH and H2O2 scavenging assay), pH, acidity, total solid contents, brix, bacterial viability, and alcohol content were evaluated during 14 days storage time at 4 ◦ C. The best sample was selected based on sensory evaluation, TPC and antioxidant activity (scavenging activity aganist DPPH and OH radicals). Resullts and discussion: The results showed that fermentation process increased TPC, antioxidant activity, and acidity while reduced pH, total solid content and brix. Therefore, the selected bacteria, amounts of honey (5% w/v) and floral water of mint (1, 2 and 3% v/v) used in production of the beverages can affect the quality and sensory properties of quinoa-based beverages. The bacterial population during 14 days storage at 4 ◦ C was in the range of proposed for functional food products (at least 106– 108 CFU/ml). According to the results obtained, the sample containing 5% honey with 3% of mint floral water was selected as the best sample based on higher sensory characteristics among other samples. Conclusion: The quinoa-based gluten freen fermented beverage containing 5% honey and 3% of mint floral water can be considered as a functional beverage. Furthermore, it may be concluded that the prepared the beverage due to its potential capability to support the survival of probiotic bacteria may potentially be developed as an appropriate non-dairy carrier for probiotics. But, our product must be investigated further for in-depth nutritional characteristics. Attempts may be made to enhance nutritional value and shelf life of the prepared functional beverage. Lactic acid bacteria may synthesize several bioactive compounds such as vitamins, exopolysaccharides, enzymes, antioxidant, antimicrobial, and cholesterol lowering substances which may contribute towards enhanced functional attributes of foods.

Introduction: The complex composition of the essential oils and the variety of chemical structures of their constituents are responsible of a wide range of biological activities many of which are of increasing interest in the field of foodstuff preservation (Romanazzi et al. 2012). Regarding that higher amount of EOs are required for food preservation, their application can negatively influence taste or odor. To avoid this unwanted side effect, several EOs can be combined. On the other hand the synergistic possible effect produced by the combination of plant essential oils was referred as an efficient strategy to combat microbial development(Wagner. 2011). The main purpose of this study was to evaluate the antifugal synergistic effect of combination of some essential oils including thyme, cinnamon, rosemary and marjoram aginst apple rot fungi during posthrvest storage. Material and methods: In this experiment, chemical composition of the essential oils was analyzed by gas chromatography. For evaluation of antifungal activity based on MIC, against Alternaria alternanta, Penicillium expansum and Botrytis cinerea, an agar dilution method was used. EOs interactions were assessed using a checkerboard microdilution method. The evaluated concentrations were in the range of 5 dilutions below the MIC to twice the MIC. For the double combinations, a two-dimensional checkerboard with twofold dilutions of each EOs was used (six double combinations). Results and discution: The maximum antifungal activity was demonstrated by thyme oil which showed MIC values 1250 μ g/mL for A. alternanta and P. expansum and 625 μ g/mL for B. cinerea. Cinnamon oil with MIC values1250 μ g/mL against A. alternanta and B. cinerea and 2500 μ g/mL against P. expansum displayed more inhibitory effects than rosemary and marjoram essential oils. In antifungal synergy testing, some double combinations (thyme/rosemary, thyme/cinnamon and cinnamon/marjoram) were found to be synergistic (FICi≤ 0. 5). The in vivo assay also demonstrated considerable inhibitory effects of EO combination treatments. Results from artificial wounding of trated apple indicated that double combination of thyme/cinnamon (156, 312 μ g/mL) has more inhibitory effect than single EO treatments. Although the major components of thyme and cinnamon (especially thymol, carvacrol and cinnamaldehyde) are very important for their antifungal activity, other less-active compounds in rosemary and marjoram (such as α – Pinene, 1. 8-cineole, Terpinene-4-ol and γ-Terpinene) play a significant role, as they can strengthen the effects of major components, though synergistic effects have also been observed.

Introduction: One of the oldest methods for the preservation of food is drying, which consists in removing water from the product in order to provide microbiological safety and the most popular drying method includes convection (Hassan-Beygi 2009; Salehi et al. 2014). One of the ways to shorten the drying time is to supply heat by infrared radiation (IR). Application of infrared heating to food drying is recently of special interest because of the progress in radiator construction. Their efficiency is between 80% and 90%, the emitted radiation is in narrow wavelength range and they are miniaturized (Pan et al. 2008; Salehi et al. 2014). Modeling of agricultural products drying is one of the best ways to controlling the drying time and conditions. Artificial neural networks (ANNs) are information processing networks constituting a set of highly interconnected neurons arranged in multiple layers that can be trained to fit one or more dependent variables to any degree of accuracy using a set of independent variables as inputs. ANNs were successfully applied to problems from various areas including business, medical and industrial fields. Once the ANN is trained using experimental data, it can be used in a purely predictive mode to calculate the dependent variable(s) for any values of input variables. Process modeling is an area where ANNs of various configurations and structures have been considered as alternative modeling techniques, particularly in cases where reliable mechanistic models cannot be obtained. Genetic algorithm (GA) optimization technique can be used to overcome this inherent limitation of ANN. GA are search techniques for an optimal value, mimicking the mechanism of biological evolution. They have a high ability to find an optimal value (global optimal value or at least near global one) of a complex objective function, without falling into local optima. The mathematical chromosomes could be operated upon by quasi genetic operations of selection, crossover, and mutation. These three parameters are repeated until desired convergence on optimal or near-optimal of the solutions is achieved. Mutation is a genetic operator that alters one or more gene values in a chromosome from its initial state. Mutation enhances the GA ability by intermittently injecting a random point in order to better search the entire parameter space, which allows the GA to possibly escape from local optima. This can result in entirely new gene values being added to the gene pool. With these new gene values, the GA may be able to arrive at a better solution than was previously possible (Ramzi et al. 2015; Salehi and Razavi 2016). Material and methods: Fresh apricots were obtained from market. Slices of apricot with 5 mm thickness were prepared with the aid of a steel cutter and were immediately placed into the dryer. The apricot slices were dried in an infrared dryer. In this study, for drying and increasing the shelf life of apricot, infrared radiation method was used. The effect of infrared lamp power at three levels 150, 250 and 375 watts, the distance of lamp from sample at three levels 5, 7. 5 and 10 cm and time of 160 minute on drying of apricot were examined. Modeling of process was done with the genetic algorithm– artificial neural network (GA-ANN) method with 3 inputs (lamp power, distance and time) and 1 output (weight loss). Results and discussion: During drying, radiation properties of the material are changing due to decreasing water content. As a consequence, its reflectivity increases and the absorptivity decrease. Generally, solid materials absorb infrared radiation in a thin surface layer (Pan et al 2008). The effects of infrared power and distance on the moisture content of apricot slices are shown in Figures 3 and 5. As expected, the moisture content was decreased by increasing the power because of the increased temperature and heat transfer gradient between the air and samples. The weight loss of apricot samples were 36. 34, 52. 00 and 87. 90 min at 150, 250 and 375 W, respectively (32 min and 10 cm). In conclusion, experimental results showed that the infrared power has a significant effect on the evolution of moisture content. Hence, drying of thin layers seems to be more efficient at far-infrared radiation, while drying of thicker bodies should give better results at near-infrared radiation (Nowak and Lewicki, 2004). The weight loss reduced from 87. 43 to 78. 26 % when the distance was increased from 5 to 10 cm (150 W and 98 min). GA-ANN model was developed for modeling of apricot weight loss during drying with infrared dryer. In this study, ANN with 1– 30 neurons was trained using GA to find the optimal network configuration. It was found that ANN with 7 neurons in one hidden layer could predict apricot weight loss with high correlation coefficient and low NMSE (0. 9987, 0. 0026, respectively). The prediction efficiency of the GA-ANN model for unseen data is presented in Fig. 7. The calculated correlation coefficient value for estimation of apricot weight loss show high correlation between predicted and experimental values. Table 3 illustrates the weights and bias values of optimized network, which could be applied in a computer program for estimation of apricot weight loss during drying with infrared dryer. The results showed that an acceptable agreement between the predicted and experimental data can be achieved using GA– ANN model. Conclusion: The results of infrared drying of apricot showed that with increasing in lamp power and decreasing in sample distance from the heat source, the drying rate was increased. The GA-ANN modeling results showed a network with 7 neurons in 1 hidden layer with using sigmoid activation function can be predicting the weight loss in apricot drying by infrared method with correlation coefficient equal to 0. 9987 and mean squared error equal to 1. 9215. Sensitivity analysis results by optimum ANN showed the drying time was the most sensitive factor to control the weight loss of apricot slides.

Introduction: Kinetically stable emulsions can be formed by using emulsifiers and/or thickening agents. Emulsifiers are mainly surface-active proteins which can adsorb on the droplet surfaces lowering surface tension and preventing the droplets from coming close enough together to aggregate. Biopolymers like proteins with emulsifier property and the ability to increase the viscosity of the emulsion systems are the essential ingredients in the formation of a stable emulsion. Emulsifiers have surface-active properties with ability of formation a compact and thick interfacial layer after the adsorption on the droplet surfaces, which results in a strong steric and electrostatic stabilization against coalescence and flocculation/aggregation. Egg white albumin (EWA) is one the best choices among proteins for fabrication of food emulsions with desirable properties, owing to its great functional possessions. In food based on emulsion systems, generally, steady state flow measurements and oscillatory (dynamic) measurements are used for the characterization of food emulsions. Steady state flow measurements are used for characterizing the shear thinning nature of food stabilizer. Oscillatory experiments are used to obtain information on the viscoelastic and gel characteristics of foods. Concerning emulsion rheological behaviour, it ranges between Newtonian and pseudoplastic. Material and methods: In this study, the effect of different concentrations (0. 1, 0. 3, 0. 5, 1, 3 and 5%) of albumin on physical, rheological properties, as well as microstructure of oil-in-water (O/W) emulsions (20% wt/wt) were investigated. The emulsions were prepared by dispersing 20% (w/v) sunflower oil in the albumin solution (0. 1-5%). Primary emulsions were prepared using an Ultra-Turrax blender at 11, 000 rpm for 2 min. Fine emulsions were then prepared by homogenization of the primary emulsions using an ultrasonic apparatus for 2 min. Creaming was measured during 12 days. The rheological properties of samples were measured using rheometer. Frequency dependency of storage modulus and loss modulus can be calculated by Power law model. The amount of b and d is closer to zero when the frequency dependency is low, the higher amount of b represents the elastic characteristic of the samples, it is more than zero for physical gels, and zero for the covalent gels. Microstructure of the emulsions was studied at room temperature using light microscope. The experimental data were analyzed using SPSS statistical software. The rheological data fitting was done using Rheoplus software (Version 3. 4, Ostfildern, Germany). Significant differences between the means of different treatments were determined by Duncan’ s multiple range tests (P<0. 05). Results and discussion: The results showed that the stability of the emulsions containing 0. 1% albumin was 67% while it increased to 95% with increasing the concentration of albumin to 5%. After 12 days of the storage at ambient temperature, there was less creaming observed for the emulsions containing higher concentration of albumin. Results of the flow behaviour test demonstrated a decrease in the viscosity of the samples resulted from the shear rate increasing, leading to the emulsions exhibiting a shear thinning behaviour. These behaviors can be explained with ordering of emulsion droplets along the flow direction due to overcoming Brownian motion with increasing shear rate, which causes a decrease in resistance to flow and thus, decreases the viscosity. Due to a hysteresis area, the emulsions presented a thixotropic behaviour. Carreau was recognized as the best model for describing the rheological data in the current experiment. Emulsions containing 0. 3% albumin had the highest zero shear viscosity, hysteresis area, and apparent viscosity (measured at constant shear rate of 50 s-1). Data of the strain sweep test showed that LVE was about 0. 1%. In the emulsions containing different amounts of albumin, storage modulus was more than loss modulus and both increased with the frequency. In the case of the emulsion containing 0. 3% albumin, the storage modulus was the maximum. Tan (δ ) and complex viscosity increased and decreased, respectively, at frequency sweep test. Power low model described the frequency sweep data properly. Microstructure of emulsion showed that emulsions containing high albumin content (5%) demonstrate a considerably uniform size of droplets and amount of large droplet was decreased. Conclusion: Taken together, the results of the current study showed that the addition of albumin, as the natural emulsifier, up to 5% could improve the stability of the egg albumin emulsions, due to its emulsifying properties. This sample can be used in foods based on emulsion system.

Introduction: Nowadays, consumers are more conscious about their diets and pursuit for healthy foods. Healthful diets that are low in fat and rich in fiber may diminish the risk of some types of cancer, particularly colon cancer, a disease connected with many other complaints. Furthermore, such healthful diets are also associated with a reduced risk of type-2 diabetes, a condition that causes a person's blood sugar level to become too high. Continuing problems from high blood sugar may result in heart disease, knocks and diabetic retinopathy which may cause blindness and kidney failure. However, despite a recent trend toward healthy eating behaviors, many consumers still tend to consume unwholesome foods since they make their eating choices just based on food taste. Food texture becomes especially imperative as customers try to find food products containing reduced fat and calories but are not willing to accept inferior eating characteristics. Gums and mucilages are broadly used by food industry to improve food texture and to keep product quality throughout the storage period. Like gums, mucilages are plant hydrocolloids that are similarly formed mainly of galactose, methyl pentose, and pentose sugars linked by glycosidic connections to uronic acid residues. Besides of their gel creating and water holding ability or capacity, mucilages delay gastric emptying. In the present work, the possibility of incorporation of psyllium husk mucilage (PHM), basil seed mucilage (BSM), and cress seed mucilage (CSM) as fat-replacers in the formulation of semi-solid low-fat chocolate dairy desserts was evaluated. Material and methods: The experiments were designed according to a 3-level-3-factor central composite design (CCD) using response surface methodology (RSM). In the formulation of semi-solid low-fat chocolate dairy desserts, three mucilages including PHM, BSM, and CSM (each at the levels of 0-0. 2%) were used as the fat-replacers. The responses of interest were the flow behavior (apparent viscosity, consistency index and flow index), rheological properties (storage and loss modulus) and particle size distribution of low-fat chocolate dairy desserts. Results and discussion: The results indicated that fat reduction caused significant increase in the flow index of semi-solid low-fat chocolate dairy desserts. All the samples exhibited shear-thinning flow behavior; however, fat reduction significantly (p<0. 05) resulted in decreased apparent viscosity, G’ , G” and consistency index. In the other word, reduction of fat increased the hardness of low-fat chocolate dairy desserts in terms of rheological parameters fracture stress and Young’ s and storage moduli. The fracture stress and Young’ s modulus are generally considered as indices of dairy product’ s softness, i. e. the higher the uniaxial compression parameters, the firmer the dessert. Storage modulus increased with frequency for all samples reflecting the relaxation of more bonds with more structural rearrangements when the time scale of applied stress was longer. Moreover, storage modulus values were higher than loss modulus values for all the samples over the entire frequency range, indicating the dominant elastic character of the desert samples. Consistency index of all the desert samples were ranged as 3. 50-21. 82. As expected, as the fat content of desert samples were reduced, the consistency index was significantly decreased. However, incorporation of mucilages in desert formulation fairly compensate this factor and increased consistency index and resembled it to its full fat dessert. The results of particle size distribution indicated that in the absence of fat (control low-fat dessert), frequency of larger particles increased considerably whereas, incorporating the optimum levels of gums into the formulation of the low-fat dessert shifted the particle size distribution curve to the smaller particle size region. Conclusion: Mucilages are generally normal products of plant metabolism which have several function properties such as mass reduction, nutrient confiscation, as well as a source of protection in contradiction of grazing and ingestion, and heavy metal illumination. This research was performed to investigate the effect of addition of some mucilages as fat replacers on rheological behavior and particle size distribution of low-fat chocolate dessert. Results of present study indicated that addition of tested mucilages could be an effective technique to improve textural properties of semi-solid low-fat chocolate dairy desserts. RSM result demonstrated that using optimum formulations of 0. 17% PHM, 0. 05% BSM and 0. 05% CSM for semi-solid low-fat chocolate dairy desserts would result in reduced-fat products with acceptable rheological and organoleptic properties. Besides being used as a fat replacer and rheology modifier, mucilages could be added as a functional ingredient due to its well-established prebiotic and health promoting effects.

Introduction: Keeping fish in crushed ice will preserve the nutritional quality of the food and its ingredients. Keeping fish in crushed ice will preserve the nutritional quality and its ingredients. Enzymes and microorganisms immediately begin to fish spoilage and cause the production of compounds that lead to the destruction of fish and its unconsumption. The keeping fish in ice in the market until consumption without fish being frozen is good method for its preservation. Even if the fish are frozen immediately after the catch, it is necessary that with the precision and the speed required, it kept under cool conditions in the refrigerator, it is still not possible to ensure that the product remain its qualitative characteristics for a suitable period of time. Although the activity of the bacteria stops at temperatures of-10 ° C, but during the storage of fish in the freezer, chemical reactions (enzymatic and non-enzymatic) even slowly continue at temperatures of-30 ° C. They will cause organoleptic properties changes and weight loss and fish fat changes. These processes lead to unwanted changes during storage and thus reduce product quality. The aim of this study was to study on effect of fish Siganus javus storage time in ice powder on proximate composition and organoleptic properties. Material and methods: The number 8 health and live fishes of Siganus javus randomly were elected from Dylam Bander, with same size and an average weight of 200± 3500 g. Fishes for 20 days were placed in polystyrene boxes in layers of powdered ice with ratio 1 to 1 and with thickness of approximately 5 cm. The sampling was carried after 1, 4, 7, 10, 13 and 20 days. The after removing wastes, samples were washed with water and then fish fillets were transferred to Ahvaz veterinary laboratory for analysis of chemical compounds. The method (AOAC, 2005) was used for analysis of proximate composition and peroxide index. The sensory evaluation parameters were determined by five test panelists based on Lane and Morris method. The results showed proximate composition was changed under of ice cover. Results and discussion: The results showed that samples in tenth day, found with highest protein content. Different time periods in ice cover significantly were affected on fish sensory evaluation, so that the quality of fish was decreased with time. The results of crude protein measurements showed a decreasing and increasing in fish fillets studied during the maintenance period. The statistical test showed that there was a significant increase between the mean values of crude protein on the first day (zero) and the last day of storage (twentieth) (P<0. 05). The amount of protein in the first day of storage was 65. 68%, which increased significantly to the tenth day to 74. 57%, then the factor was decreasing and on the twentieth day it reached 40. 52%. This change was also statistically significant (P <0. 5). Reducing the amount of proteins during storage can be attributed to the production of broken polypeptide chains and the denaturation of proteins and the conversion of nitrogen to volatile compounds, and these processes were carried out in inappropriate temperature conditions and carrying out microbial and enzymatic activities. The amount of fish peroxide was changed during the ice-cover period, with the lowest amount observed on the tenth day, and then increased again. But in all periods of testing, its value was lower than the standard. The reason for the increase in peroxide is the increasing the effect of lipase on fat and its conversion into fatty acid and the conversion of fatty acid to peroxide. Reducing the amount of peroxide is probably due to the effect of some cellular compounds in the muscle of the fish, which in this way prevents the progress the fat oxidation. The researchers report that in different species of fish, decreasing the amount of protein by increasing the storage period in the vicinity of ice is likely due to protein degradation and its increase is due to the reversibility of this process. Conclusion: It is concluded ice cover prevents from spoilage until fourth day only. The fish storage period in affected on the fish nutrient composition and it decreased fat and ash contents and increased moisture content. Based on the results of this study, although ice use is a cheap and effective way to reduce temperature and storage of fish, but long-time storage in ice has reduced the quality and fish nutrition value.

Introduction: Heating of milk for the purpose of removing the bacterial pathogens should be done for the shortest time, and sufficient pasteurization must be ensured. The limitation of the classical methods of pasteurization is due to the high sensitivity of the milk to coagulation by the application of high temperature, which sometimes prevents the proper process and causes problems such as milk clotting and the formation of non-washable layers (milk stones) on the interior surface of the pasteurization tubes. These layers prevent the sufficient heat transfer and the adequacy of the pasteurization of the next inlet milk, and as a result, the mentioned milk contains high levels of microbial contamination that will be hazardous to consumers. Therefore, the aim is to find a suitable pasteurization method that does not have the above-mentioned disadvantages and also the milk obtained from the pasteurization process will have a higher quality. Therefore, in this research, the inductive electromagnetic flow heat was used for pasteurization of the milk. In this method, the milk container acts as the second coil of the electromagnetic current (transformer) and allows direct flow of electricity in the milk. In the preparatory steps of the project (stages 1 to 3), whose results are not mentioned in this article, milk pasteurized was done by induction heating in an attempt to modify, revise, and refine the usual classical process. In order to obtain the best conditions for milk pasteurization by the induction method, the effect of four different factors were investigated, namely three diameters of the test vessel (23, 17 and 12 cm), three electrical conductivities (350, 1000 and 1600 watts), three temperatures (72, 75 And 84 ° C), three storage periods at pasteurization stage (15, 20 and 30 seconds) and three replications; Where 243 samples were selected in a completely randomized factorial experiment design. And the tested samples were categorized based on 1) the lowest percentage of residual microbial load, 2) the minimum time spent for pasteurization, and (3) the least Energy consumption for pasteurization. Material and methods: Three selected samples in the third stage of the previous project were prepared using the standard method in this study with the correct mixing at a certain temperature and used for the organoleptic test by the taste Group during the following steps. 1) Selection of 10 panelists. 2) Explaining the method and providing relevant questionnaires; 3) Checking and assuring the qualification of the panelists for evaluation (no smoking, medication, etc. ); 4) explaining the evaluation method to the testers. Then, the physical and organoleptic characteristics of the produced samples were determined by the panelist group using a grading method based on the color, aroma, taste, texture, consistency and concentration of the samples. Results and discussion: In the samples pasteurized using the induction pasteurization method with 1600 W power transmission intensity, 30 seconds holding time, temperature of 84 ° C and 23 cm cross section of the container, desirable organoleptic and physical properties were obtained compared to the other samples and the control (pasteurized under conventional conditions). So, there was a significant difference between consistency, concentration, and aroma and customer satisfaction in two treatments at the level of 5% confidence and for the color attribute at 1% level due to the high speed of heat transfer in milk. Conclusion: The induction method of pasteurization is superior to the HTST method in favor of the production of desirable organoleptic properties, and is a very good substitute for the classic method of the factory under the same conditions.

Introduction: pumpkin is a cultivar of a squash plant, most commonly of Cucurbita pepo, that is round, with smooth, slightly ribbed skin, and most often deep yellow to orange in color. The thick shell contains the seeds and pulp. It is native to North America. Pumpkins are widely grown for commercial use and are used both for food and recreation. Pumpkins with high nutritional value has many applications in food and medical industries. The color of pumpkins derives from orange carotenoid pigments, including beta-kryptoxanthin, alpha and beta carotene, all of which are pro vitamin A compounds converted to vitamin A in the body. Pumpkins are very versatile in their uses for cooking. Most parts of the pumpkin are edible, including the fleshy shell, the seeds, the leaves, and even the flowers. Pumpkin puré e is sometimes prepared and frozen for later use. The dried pumpkin can be stored for a long period of time due to low activities of microorganisms and enzymes resulting from lower water activities in the final dehydrated products compared to fresh once. This leads to high shelf life which contributes to food security. Pre-drying treatments like dipping in salt and sugar solutions could also be used to improve quality. Pre-drying treatments could be used to preserve color and flavor, minimize nutrient loss, stop decomposition enzyme action and ensure more even drying and to extend storage the shelf life of pumpkin. Similarly, the osmotic dehydration is carried out to improve food quality by inactivating enzymes, reducing microorganisms and preserve the natural color when pumpkin after osmotic dehydration is subjected to drying. In osmotic dehydration, by immersion in a high pressure solution, the water flows out of the cell membranes of the product, then flows into the intercellular spaces and finally reaches the solution. The purpose of this research was to evaluate the effects of pre-drying treatments and methods of drying on some chemical qualities of pumpkin fruit and produce dried pieces of pumpkin for direct consumption or addition to other products for enrichment. Material and methods: The required pumpkin fruits in this study was prepared from Mashhad in fall season. The fruits were completely healthy due to their apparent, texture and microbial properties. The fruits were washed, peeled and cut into uniform cubes of 1 cm. The fiber and seed were scraped off. then, soluble solids, color parameters (L* a* b*), pH, acidity, wet matter, reducing sugar of fresh pumpkin were measured. In this study, there were 2 osmotic solutions, salt solution (3, 6 and 9 percent) and sugar solution (40, 50 and 60 percent). pumpkin slices were weighed and then dipped in the salt and sugar solutions for 45 minutes for osmotic dehydration separately. Finally, the slices were drained well and spread for drying using three drying conditions. they dried in lab drier with hot air, in sun and shade. Drying slices was continued until the moisture content of the samples reached 15%. Rehydration, firmness and color parameters of dried pumpkin slices were measured. The statistical model used was factorial experiment based on a completely randomized design. The experiments were performed in 3 replications and data analysis and comparison of means were done in Duncan test using Mini Tab software. Results and discussion: Two kinds of salt and sugar osmotic solutions were used to increase the drying speed of the pumpkin samples. Among salt solutions, 9% solution of salt resulted in the production of better color in pumpkin samples, but the texture of the samples was stiffer. among different concentrations of sugar solutions, 40% solution created more suitable color and texture in dried samples than other solutions. The texture stiffness of the pumpkin slices that were pre-processed with sugar solutions were higher than those pre-treated with salt solution, but they were better in color. Since the dried samples pumpkin are exposed to heat during use, the stiffness of the tissue is eliminated. Among the different methods of drying the pieces of pumpkin, drying in the shade due to the lack of electric energy had economic justification. Also drying in the shade, had the least adverse effect on sample pigment destruction. Conclusion: The concentration of sugar solution in pretreating of pumpkin samples for drying, for creating desirable color and texture, was determined 40%. Drying of pumpkin in shade, because of remaining the color and economic reasons, was approved.

Introduction: Consumption of high fat diet is associated with various chronic diseases. This association has created increased consumer awareness and an increase in the demand for low-fat foods, including cheese (Nishinari et al., 2000). However, the consumption of low/reduced-fat cheese is still low demand between consumers. Low-fat cheese faces great challenges associated with its texture being hard and rubbery and lack of flavor (Olivera et al., 2011). In an effort of improving the quality of low-fat, different hydrocolloids could be used. Ultrafiltered processed feta cheese is the major industrial produced cheese in Iran and is very popular between consumers. Because of having high fat content, in this research feasibility of lowering fat in ultrafilterd feta cheese through substitution with xhantan gum have been surveyed. Material and methods: To prepare low fat feta cheese, raw milk was passed from ultrafiltration system to reach 34% solid non-fat then fat content of retentate was decreased from 16% to 8% by skim milk addition. The xhantan gum at the levels 0 (control), 0. 1, 0. 3 and 0. 5% based on retentate content was added. After inoculation with lactic acid bacteria and chymosin, coagulation was performed at 30oC for 20 min. The 3% salt was poured to all of the samples equally and maturation conducted at 27oC until pH 4. 6. The prepared samples were evaluated for chemical properties (pH, acidity, salt, fat and solid non-fat, lipolysis and proteolysis), texture properties (softness, chewiness, gumminess, and springiness) and overall acceptability during storage period 0, 15, 30 and 45 days of storage. Preparation of treatments were carried out in triplicate and the data obtained from the above mentioned evaluation parameters were analyzed based on Factorial design and Duncan's multiple range comparison test. Results and discussion: The results showed that the amount of gum addition had no significant effect on fat content, whereas pH and solid non-fat content decreased significantly by adding gum (p<0. 05). Control and samples containing 0. 5% xhantan gum had the least and the most moisture content, respectively. The intensity of water holding capacity as a result of fat to protein balance lowering along with fat reduction has been mentioned by Volikalis et al., 2004. Ratio of lipolysis as milk fat degradation and proteolysis as decomposition of proteins indicator were increased in parallel with xhantan gum addition. Lipolysis is a water content dependent reaction so this phenomenon was occurred in a lower rate in full fat cheese (control) as a result of lower moisture content of them (Kwak et al., 2004). Presence of hydrocolloids probably due to water entrapment in cheese matrix could be lead to free fatty acid release. These indices also increased during the storage period until the 45th day (p<0. 001). Gradually increment of soluble nitrogen during storage period is a common phenomenon and described as maturation and flavor development in cheese but its increase along with xhantan gum addition could be interpret by Zhisu and Shah (2005) expression which they have mentioned a parallel relationship between moisture content and proteolytic enzyme activities. The texture profile analysis resulted that cheese samples prepared with 0. 5% xanthan gum, had low softness, whereas springiness, gumminess and chewiness of them increased. Also, based on panelist judgement, xhantan gum addition lead to lightness and whiteness lowering and was an undesirable but from the overall acceptability viewpoint, UF white cheese prepared from 0. 5% gum got the best score. Conclusion: It was concluded that to achieve a low fat Uf-feta cheese, use of xhantan gum could be an appropriate choice. It did not cause any adverse effect on taste and other sensorial parameters which is the main reason of cheese selection by consumers. The addition of xhantan gum improved the texture of low-fat UF-cheese by reducing the hardness, gumminess, and chewiness which has been challenging and a universal complaint about low-fat cheeses.

Introduction: Rogen bread is one of the loaf bread, with a relatively short shelf life. In this study, the effects of different modified atmosphere packaging (MAP) on moisture content, microbial changes and sensory properties of rogen bread during five days storage were investigated. Material and methods: Bread was prepared using the formulation presented by Sahar Bread Factory and immediately transferred to the packaging lab. Breads were packed after being transferred to the laboratory by a packaging machine designed to form headspace and injected into polyamide polyethylene bags, then the qualitative characteristics of the bread included, microbial and sensory storage were maintained for five days (In the first, third and fifth days of storage, the room conditions (25 ° C and relative humidity (38 ± 2%) were tested. In this study, sensory analysis of bread was evaluated through parameters such as crust rupture, shell color and texture color, flavor, internal wall porosity, tissue porosity, chewing ability, form and shape of the bread, and ultimately overall sensory score. Head space gases in the present study included: air (control), 100% N2, 100 CO2%, 70% N2: 30% CO2, 30% N2: 70% CO2, 50% N2: 50% CO2 were tested at ambient conditions (25 ° C and 38± 2% RH). Results and discussion: The results of the study showed that, by increasing the storage period, increase in moisture content was observed in all the samples, control had the highest change, and gas combination treatment had the lowest change. In the present study, in all treatments, the moisture content of bread crust increased until the third day (Table 2), and there was no change in the majority of treatments until the fifth day (except for control treatment and 100% nitrogen treatments). This phenomenon is related to the difference in moisture content between the crumb and the crust, which, as a driving force, results in the migration of moisture from the crumb to the crust and ultimately into the surrounding environment. Over time, the reduction in this difference leads to a decrease in the rate of loss of moisture (Piazza and Massey 1995). The results of changes in the total count of microorganisms in Table 3 showed that the total count of microorganisms in the control treatments and treatments of 100% carbon dioxide and 100% nitrogen in the first day was log CFU /g. Nitrogen and carbon dioxide combinations were not observed in microorganisms during the whole period of storage. The gases used in the modified atmosphere, such as carbon dioxide, have antimicrobial properties, and its mechanism is that it dissolves into the water and produces carbonic acid, which carbonic acid is introduced from the cellular membrane of the microorganism and into the cell It is ionized and by interrupting the electrical balance inside the cell causes the death of microorganisms. The other reason for the reduction of microbial growth in modified atmospheric samples is the absence of oxygen in these packages, in addition to the antibacterial and antifungal effects of carbon dioxide, in addition to the antibacterial and anti-fungal properties of carbon dioxide (Sortsev et al. 2002; Orekole 2003). The results of this study were consistent with the results of studies by Conver et al. (1985), Fernandez et al. (2006) and Dergmynchuklu et al. (2011). Results of changes in mold and yeast in Table 4 showed no control except for the remaining treatments during the whole period of mold and yeast storage, and on the first day, the mold and yeast content were zero in control treatment but significantly increased with increasing time Found (P <0. 05). Some other researchers investigated the use of modified atmosphere packaging (MAP) to extend the shelf life Iranian flat bread including Barbari and Sangak breads. Four treatments of atmospheres including 100% CO2, 70% CO2 – 30% N2, 30% CO2 – 70% N2 and normal air were used. Results showed that it is possible to prolong the shelf life of breads to about 17 days by using modified atmosphere packaging with high carbon dioxide concentration and high-barrier laminated. However, significant differences (P<0. 05) were obtained in the firmness of control bread compared to another treatment. Conclusion: It seems that, modified atmosphere packaging including 50% N2: 50% CO2) and 30% N2: 70% CO2, respectively cause better quality of rogen bread than other conditions during storage.

Introduction: Coating of fresh-cut fruits by biopolymer coatings containing bioactive materials are one of the methods and effective ways to prevent undesirable quality changes during storage. Enzymatic browning is an important factor in reducing the shelf-life of freshly squeezed apples, which is due to the release of the enzyme and its contact with the substrate (phenolic matter) through the cutting. Formulation and production of active carboxymethylcellulose-pectin-based active coatings containing citric acid and ascorbic acid and their effectiveness in improving the qualitative characteristics of apple peelings, which have been peeled during storage. In the present study, natural substances found in fruits were used for coatings formulations and a mixture of pectin-carboxy methyl cellulose polysaccharides as based biopolymers and ascorbic acid and citric acid were used as materials inhibited enzymatic browning. Measured tests include determination of weight loss Samples were weighed after 9 days of storage in cold storage. Also, tissue texture determination and determination of tissue firmness using a manual pentometer, soluble solids content (Bx) with refractometer, titreable acidity in malic acid in 100 ml of juice, colorimetry of samples using a device The colorimetric method was evaluated based on Hunterlab's parameters and Photoshop software and Sensory Hedonic test (consumerism) by 10 randomized (from female students 22 to 25 years old) and 5-point method. Material and methods: At first, optimization of active-blend edible coating formulation was investigated by response surface methodology (RSM) based on the minimum a * (red-green) in fresh-cut apples and for this purpose, central composite design with three variables (concentration of carboxymethyl cellulose-pectin, ascorbic acid and citric acid) three replicate and 18 treatments were used. Results and discussion: In this way, the coating solution of containing 3. 14% carboxymethyl cellulose-pectin, 1. 17% ascorbic acid and 1. 17% citric acid (%w/v) was determined as best coating solution. Then effects of optimized coating on quality of fresh-cut apples were studied. Conclusion: Although there is no significant difference among coated and uncoated apples after 9 days (P<0. 05) but the results of firmness test showed that coated fresh-cut apples maintain initial texture better than control. The acidity values were higher in coated apples compared to un coated apples (0. 41 and 0. 17, respectively). Coating caused to decrease in overall color change of fresh-cut apples after 9 days. The use of coating resulted to better flavor, texture, color, aroma and appearance acceptability in comparison to the control sample and there is a significant difference at the 5% level between the samples. Comparison of the data on the content of soluble solids in coated and uncoated peelable apples showed that the difference was not significant at 5% level. Hunter's colorimetric parameters were compared to the coated peelable apples and uncoated samples at day 1 and ninth of storage. Δ E in fact, the degree of color difference shows the samples of the ninth day with the first day. The values of Δ E for the coated sample are lower, the values of the color parameters (a, b and L) are less pronounced in the coated sample than in the first day. Edible coatings can delay the progress of this reaction by reducing the contact of oxygen with fruit tissue, as well as the presence of anti-browning agents such as ascorbic acid and citric acid in active coatings, exacerbating the inhibitory effect. Which can reduce the pH and hence decrease the activity of the enzyme in the phenolase and make the copper cofactor chelate. The results of the Hedonic evaluation of peeled apples showed that there was a significant difference in the level of 5% between the final color absorbance of coated samples and uncoated samples. Sensory evaluators significantly increased the scoring of the samples and more accurately recognized it. The results of analysis of variance showed that the final aromas of freshly squeezed apples were affected by the coating and prevented the decrease in aroma. After 9 days of storage, the taste of the coated samples was score higher.

Introduction: Grape seed oil includs high contents of linoleic acid (68-76 %) which is essential fatty acid for human and necessary for body textures. despite being rich in essential fatty acids, grape seed oil has low oxidative stability which can be increased by using different methods such as mixing with the other oils that have high oxidative stability. Between vegetable oils, sesame oil is one of the most stable one against oxidation. This can be because of high percent of antioxidant phenolic compounds. The aim of this study is mixing grape seed oil with sesame oil for incresing the oxidative stability. Material and methods: In this study, samples of different proportions of sesame oil (0, 25, 50, 75 and 100 %) were mixed with grape seed oil (100, 75, 50, 25 and 0 %). The samples were evaluated for fatty acid profile, physicochemical properties and antioxidant activity. The iodine number was measured by Hanson method in edible oils and fats. The calculation of peroxide number was carried out according to AOCS No. 53-8 Cd method. The oxidative stability was evaluated applying the Rancimat method. In order to determine the composition of fatty acids, the methyl ester of fatty acids was prepared according to National Iranian Standard No. 4090. Then, analysis of fatty acids was carried out with a Gas Chromatography (China Techcomp Model) equipped with flame ionization detector according to AOAC No. 22/963. Total phenol and total antioxidant activity were measured according to Jannat et al. (2010) method. The total antioxidant activity was evaluated according to the iron oxidation antioxidant capacity assessment method described by Benzie and Strain (1996) and the absorbance of the samples at 593 nm was measured by Japan's Shimadzu Spectrophotometer. Measurement of phenolic compounds of all samples was performed on the basis of the Folin-Cyclotomy colorimetric method described by Velioglu et al. (1998). All tests were performed in three replications and analyzed in a completely randomized design using SAS software (version 9. 29). To compare the mean of different characteristics, Duncan's multiple range test was used at 95% probability level. Results and discussion: The results show that the highest percentage of fatty acid in various samples (sesame oil, grape seed oil and mixed ratios of these oils) is related to linoleic acid, followed by oleic acid, palmitic acid and stearic acid. In general, linoleic acid was the dominant component of sesame oil (42. 52 %) and grape seed oil (62. 50 %). By increasing the proportion of sesame oil from 25 to 75 %, the linoleic acid content of the samples decreased. While oleic, palmitic and stearic fatty acids increased in combined samples. The highest and lowest index of peroxide was related to grape seed oil (7. 21 mg /kg) and sesame oil (2. 34 mg /kg), and with increasing the proportion of sesame oil in the oil mixture, the peroxide index significantly decreased (p≤ 0. 05). The amount of iodine number of pure sesame oil samples (102. 41 g /100 g) was less than grape seed oil (128. 53 g /100 g) and increasing the proportion of sesame oil in the oil mixture reduced the iodine number of the samples. The content of phenolic compounds and the antioxidant power of sesame oil (204. 43mg/l) was higher than grape seed oil (231. 01 mg/l). The results of sensitivity measurement of pure oils and their mixture to oxidation one week after extraction, by Rancimat test showed that the highest and lowest stability was related to sesame oil and grape seed oil. With increasing the proportion of sesame oil in the oil mixture, the stability level increased significantly (p≤ 0. 05). According to the National Iranian Standard No. 5950, the minimum stability value (in 110° C) is 12 hours. Thus, the stability of sesame oil (21. 21 h) and the mixture of grape seed oil and sesame oil (12. 79-18. 42 hours) was acceptable within the national standard of Iran, while the stability of grape seed oil (7. 33 h) was far less than the level approved by standard. Conclusion: The addition of sesame oil to grape seed oil increased the number of phenolic compounds, antioxidant strength and oxidative stability of the mixed oil samples. Considering the price of the product and the importance of the nutritional quality and stability of the oil, combining 75 % sesame oil and 25 % grape seed oil has the best nutritional quality and lower cost than pure sesame oil formula.