مجله علوم و صنایع غذایی ایران
سال پانزدهم شماره 4 (پیاپی 77، تیر 1397)

Due to the noticeable use of palm oil as an additive in dairy industry, and the increased interest of consumer in the foods with antioxidant value, the palm oil was used in the entrapment of tea catechin, and its efficiency was compared with that of the milk fat. In the current research, the effect of type of oil phase (palm oil and milk fat), different ratios of span 80 surfactant to lecithin (0.5- 2) and varied RPMs (600-900 rpm) were investigated on the encapsulation of catechin by spontaneous emulsification method, upon which pH, creaming index, electrical conductivity, brix, refractive index, particles size and antioxidant activity were measured. The obtained results showed that an increase in PRM caused to a rise in creaming index in all samples, in particle's size in nano capsules with milk fat, and in refractive index and antioxidants activity in nano capsules with palm oil, while the increased PRM resulted in a decrease in particle's size in nano capsules with palm oil. In addition, increasing the ration of span 80 to lecithin led to increased creaming index and reduced pH and electrical conductivity in all samples, whereas it did not bring about a significant change in particle's size. Surprisingly, the Brix of nano capsules with palm oil was more than that of nano-capsules with milk fat. Generally, the palm oil nano capsules containing catechin produced from palm oil had proper features compared to the milk fat nano capsules containing catechin.

In this study, the effect of bioactive ice slurry contains ginger extract and essential oils, was evaluated on maintenance quality improvement of rainbow trout during short-term storage. Fish were stored for 16 days in three ice slurry types (containing extracts and essential oils of ginger and control samples). During the four-day intervals chemical (Peroxide, Thiobarbituric acid, Free fatty acids and Total volatile nitrogen bases), Microbial (Total Viable Count and Psychrophilic count) and Sensory (Taste, Flavor, Color, Odor Texture and Skin appearance) tests were performed. The results revealed a significant difference in the quality of samples stored in ice slurry containing ginger essential oil and extract with the control sample. Ginger extract and essential oils had a positive effect on the taste and visual quality acceptance of samples. Oxidative and microbiological decay was controlled with ginger extracts and essential oil. Using bioactive ice slurry, rainbow trout storage period was increased four days.

The aim of the present study was to compare antioxidant properties of date palm and Zizyphus extracts in two concentrations (200 and 500ppm) more over investigation the possibility of synergism interaction between them. Date palm extract in all concentrations had a significant higher effect than Zizyphus in DPPH free radical scavenging assay, total antioxidant capacity and reducing power. Furthermore, zizyphus in all tests was weaker than BHT, but date palm in 500 ppm concentration had higher total antioxidant capacity and reducing power in comparison to BHT (100 ppm), and lower from BHT (200 ppm) in these assays. Among different combinations of these extracts, synergistic effect was found in two concentrations (200 and 500) in DPPH free radical scavenging assay(in concentration 200, Zizyphus80:date palm20, Zizyphus50:date palm50 and Zizyphus20:date palm80 and in concentration 500, Zizyphus40:date palm60 and Zizyphus20:date palm80) and also 200 ppm concentration in reducing power assay(Zizyphus40:date palm60 and Zizyphus20:date palm80). The result showed that date palm in high concentration (500 ppm) had similar capacity to low concentration (100 ppm) of BHT. Combination of date palm extract and low amount of zizyphus at high concentration (500 ppm) can compete with low concentration (100ppm) of BHT.

Faba bean is a plant from the legumes (Fabaceae) family, and like other legumes, the protein of its pulse has two albumin and globulin components. Its high starch and digestible protein contents are two other reasons for its widespread cultivation. In this study, the effect of temperature at three levels (55, 65, 75°C) and hot-air speed at two levels (1 and 2 m/s) on qualitative and sensory properties of faba beans were investigated during drying process. Results showed that the highest protein content (3.21) belonged to the T2 treatment (drying at 55°C and 2 m/s). As for discoloration (ΔE), T1 (drying at 55°C and 1 m/s) with 27.66 had the lowest results. Moreover, the lowest drying time belonged to T6 (drying at 75°C and 2 m/s) with 29 minutes. The best model for drying and shrinkage were Page and Garzera, respectively. The highest shirinkage (15.2%) was in T5 (drying at 75°C and 1 m/s). According to results, the highest effective moisture diffusion coefficient 4.53 × 10-8 m2/s and the lowest activation energy 15.9 kJ/mol were reported in T6, respectively. In addition, T4 (drying at 65°C and 2 m/s) was the best treatment in all sensory properties. However, as there is no significant difference between some of treatment, Study findings suggest that T4 can be introduced as the best treatment.

In this research, the effect of storage period on specification of spreadable process cheese produced with using Konjac Glucomannan gum (KGM) and Xanthan gum (XG) was investigated. The optimized formulation spreadable process cheese in terms of sensory (firmness, flavor, spreadability, color, total acceptance), Texture Profile Analysis test (hardness, adhesiveness, cohesiveness and springiness) and pH value were investigated in 1, 45 and 90 days after production. The obtained results were analyzed with randomized complete design and Means were compared based of Duncan test. The textural evaluation results showed that during storage period, physical properties of cheese did significant changes and increased for TPA test (hardness, cohesiveness and springiness) and decreased about adhesiveness. The pH value of the final product declined during storage period. Between the sensory characteristics, firmness score and flavor slightly increased but color, spreadability and total acceptance scores slightly decreased. Of course, all of these changes in such a way that, all sensory scores were higher than the average scores and the final spreadable process cheese after 3 months storaged in refrigerator was very good to consume.

The use of nitrite as preservative and color stabilizer in meat products like hams is common. Due to its carcinogenic effects, it has negative track record among consumers. On the other hand, low concentrations increases the risk of Clostridium botolinum growth during storage and the production of toxin of botulism. By replacing this preservative with warm and natural pear wood smoke, in suggested situations, a safe product without having carcinogenic affects can be produced.Therefore, the general objective of this study was to investigate the effect of hot and natural wood smoke on the quality of chicken ham without nitrite at 15, 30, 45 and 60 minutes. In this study, treatments were smoked by warm and natural pear wood for 15, 30, 45 and 60 minutes after production, vacuumed and kept for 50 days under refrigerate condition (1-4 °C) and were examined physicochemical, microbial and the amount of compounds Benzo-a-Pyrene in 10, 20, 30, 45, 50 days. The results showed that there was a significant difference between moisture content, protein, ash and control in other treatments (P≤0.05). There was a significant difference between the control and other treatments for microbial characteristics (Clostridium perfringens) (P≤0.05). And the residual amount of Benzo-a-Pyrene was evaluated in fumigated treatments within the standard range(

Nowadays consumption of edible jelly, in different age groups is increasing due to high consumer acceptability. In formulation of this product sugar and synthetic colorings could be replaced. In this study the effects of gelatin and pomegranate juice (as substitution of synthetic dyes and flavoring agents) in formulation of probiotic edible jelly during storage time were investigated. Optimization of the product formulation through independent variables including gelatin amount 2-5% and pomegranate juice amount 1-4% in edible jelly containing Lactobacillus paracasei was performed. Samples were manufactured according to a central composite design and were evaluated for thier physico-chemical properties, probiotic count and sensory characteristics. Considering hunterLab results, L value was decreased at early stage but by increasing storage time an improving trend was seen. The highest a value was also obtained at 5% gelatin. Pomegranate concentrate had significant effect on a value and it was decreased till 2.8% during storage. Interaction of gelatin-pomegranate on pH had a positive effect which led to an increment during storages. Maximum of acceptability was obtained at 2.8% pomegranate concentrate. By increasing gelatin amount, sensory scores of samples were decreased. Evaluating probiotic viability, maximum of proliferation was detected at 18 days. According to the results, application of probiotic and pomegranate concentrate in formulation of jelly could increase acceptability and health promoting effects and also improve physico-chemical properties of the final product.

Consumer demand is growing for the nutritious and healthy snacks today. Since the snacks classification in foods with minimal nutritional value and it is one of the most popular snacks among people, especially children and teenagers, so snacks enrichment seems necessary. The purpose of this study is the replacement of 10% of the corn with soy flour and soy formulated flour with the egg properties in extruded snack production in a completely randomized design. The amount of protein, expansion coefficient, hardness, color and sensory characteristics of samples were evaluated. Image processing technique and the Image J software were used to measure the color values. The results revealed that addition of both components increased the amount of protein in snack samples. Also the results showed that more than 5% replacement of corn with these materials increased hardness and reduced expansion coefficient and L* and b* color values and the negative effect of soy flour was more than soy formulated with the egg properties. Finally the results indicated samples containing 5% soy formulated flour with the egg properties had the highest score in the sensory evaluation especially flavor and aroma in compare to the other samples.

Because of their positive effect, probiotic bacteria widely used in the manufacture of food, particularly in the production of dairy products. but having high cholesterol and lactose intolerance problem is an important restrictions on the use of dairy products. Recently, the consumption of non-dairy probiotic foods specifically non-dairy probiotic juices were developed. The aim of this study was to examine the growth trend of Lactobacillus acidophilus in the two varieties of Pomegranate juice Shahreza and Natanz. After inoculation of bacteria to each samples, they were stored at 4 ° C and changes in pH, titratable acidity, the sediment, as well as live cell counts were measured under controlled conditions at distinct times during fermentation. The results showed that there was lower survival of bacteria in Natanz pomegranate juice due to the lower pH. The microbial populations during the first week was decreased from 7.43 to 4.5 logarithmic cycles, While microbial populations of Shahreza pomegranate juice was decreased from 7.49 to 5.33 logarithmic cycle at the same time. In the second week of research, there was no bacteria detected in both treatments. Both treatments showed a significant decrease in pH, sediment and bacteria population at the end of maintenance, but the changes in acidity were not significant (p˂0.01). There was no desirable effect on sensory properties of pomegranate juice after adding probiotics Bacteria.

Effect of substitution of NaCl by KCl on lipolysis, compositional, sensory and rheological properties of UF white cheese during ripening (storage time) was studied. Four treatments of different mixtures of UF White Cheese with the ratios of NaCl⠩: 1.50% NaCl.50 KCl, A; 1.00% NaCl.0% KCl, B; 0.75% NaCl.25% KCl, C; and D as control with 3.00% NaCl were treated by dry salting to produce low salt cheese. Lipolysis was analyzed by measuring acid degree value and through gas chromatography. The compositional characteristics (moisture content, fat, total nitrogen with dry basis, water soluble nitrogen), sensory properties (flavor and body texture) and textural characteristics (force to fracture) were measured. The results of acid degree value (ADV) showed that all treatments after 15, 30, 40 and 50 days of aging, except after one day aging, had significant (p0.05) difference in the composition of cheese (moisture, fat, total nitrogen and water soluble nitrogen) after aging period. All treatments exhibited significant difference in sensory (flavor and body texture) properties. Textural properties (force to fracture) after 30 days aging showed that there was no significant (p>0.05) difference betweenA and D treatments.

Now a day, researchers are looking for to identify valuable materials to manufacture products with high quality, nutritious and have functional properties. In this sense, the aim of this study was the production of bread for diabetics using Fenugreek seed flour. For this purpose, fenugreek seed powder at levels of 0, 1, 2, 3, 4 and 5% by weight of flour was added to bread dough formulation. Then chemical composition of flour, rheological behavior of dough and qualitative, sensory and microbiological characteristics of bread samples was evaluated. The results of this study showed that the addition 3% of this powder causes beneficial changes such as increased water absorption of flour, FQN, fiber, ash, and improved sensory properties, particularly smell and taste, promotion color indices and reduce the activity of mold in the breads. This is despite that the degree of softening degree, stability and extensibility of dough, oil content, specific volume and texture of enriched breads in comparison with the control was not good. In general, the overall quality of breads fortified with 3% flour fenugreek seeds was better than others. Therefore, the regular use of this kind of breads will causes not only will be compensate the lack of constituents like lysine, Fe and Zn, but also the health of consumers especially patients with type 2 diabetes and insulin-resistant individuals will be improved.

Bioactive peptides are considered specific protein fragments that are inactive within the sequence of the parent protein. After they are released by enzymatic hydrolysis, they may exert various physiological functions. In the present study, response surface methodology was used to optimize hydrolysis conditions for preparing protein hydrolysate from whey protein, using Alcalase 2.4L enzyme. The investigated factors were temperature, time and enzyme/substrate ratio which were selected in the range 43-52°C, 65-175 min and 45-90 AU/Kg protein, respectively to achieve maximum degree of hydrolysis. Experiments were designed according to the central composite design. Each of the studied variables had significant effect on degree of hydrolysis (p

Studies on different parts of the walnut is indicate the exist of antioxidant, antimicrobial and anticancer properties. In this work, the effect of variety levels of temperature, time and solvent concentration investigated on antioxidant property of Methanol extract of interstitial tissue in walnut kernel during ultrasound process by response surface methodology statistical design. The results showed that increasing of temperature and time improved the antioxidant property, but in highest level of temperature, time and solvent antioxidant property decreased due to phenolic component oxidation and polymerization or dilution of extract. The best of condition for achieve to extract with high antioxidant based on Total phenol, DPPH and FRAP methods were 28.71 min, 39.22 oC and 416.57 ml per 25 gr interstitial tissue powder. Under these parameter yield of extraction, total phenol component, DPPH and FRAP calculated 3.706%, 22.67 (Gallic acid), 0.0108 (IC50) and 1270.05 (mMol Fe) .respectively.

Turnip (Brassica rapa) has a high health-giving properties for human. Normally, turnip is thermally treated before consumption. In this research work, the effects of various cooking methods viz., boiling, steaming, microwaving and pressure cooking on the antioxidants content (vitamin C, total phenolic and total flavonoid) and also antioxidant characteristics (DPPH radical scavenging, ferric ion reducing power and total antioxidant capacity) of tunip were investigated. Results showed that vitamin C, total phenolic and total flavonoid content of turnip decreased significantly (P

In this study, ultrasonic vacuum spray dryer was used to produce a dried powder of artichoke leaves extract.The drying process was performed in a vacuumed drying chamber at a lower temperature than the conventional spray dryers. The effects of independent variables (inlet temperature of 55-75 °C, vacuum pressure of 20-40 kPa, and solution concentration of 2-3%) were investigated on the functional (moisture content, particle size, bulk and tapped densities, flowability, and cohesiveness), reconstitution (wettability, dispersibility, and solubility) and chemical properties (total phenol content and DPPH scavening activity) of artichoke leaves extract powder with monohydrate lactose as a carrier in order to achieve the high process yield and desirable properties.The powders produced with the solution concentration of 3% showed the highest mean diameter of particle, bulk, and tapped densities, wetting angle (decreasing wettability) and total phenol content (TPC), while the values of dispersibility and solubility were the lowest. The increase in the inlet temperature and decrease in the vacuum pressure resulted in the particles with lower moisture content, bulk, and tapped densities as well as higher dispersibility and solubility. Chemical properties were influenced by the vacuum pressure and inlet temperature variables, both in a negative manner. The key results indicated that the solution concentration of 3%, inlet air temperature of 75 °C, and vacuum pressure of 20 kPa were the best conditions for artichoke leaves extract drying under the vacuum spray drying conditions.

Iranian paddy (Shiroudi cultivar) has poor milling yield. So, parboiling process has been used for improving its milling quality. In this study, Shiroudi paddy was soaked and steamed at 65oC for 180 min and at 96oC for 2 - 10 min, respectively. After steaming, samples were dried in the shade (27±1 oC temperature and 20±5% relative humidity) to achieve a final moisture content of 11±1% (w.b.). Final, the effect of various steaming times on degree of starch gelatinization (DSG) and some quality properties of rice (head rice yield, color value and rupture force) were investigated. Results show that the DSG, color value and rupture force increased significantly (P

Despite the numerous health effects of the dietary fibers, the amount of the fiber in the diet is generally lower than the recommended value. Therefore, increasing the fiber content of the foods particularly those of high consumption can compensate for the shortage of the fiber in the diet. However, it seems a difficult task since increasing the fiber content can have adverse effects on product acceptability. The main objective of this study was to include apple fiber in the sponge cake recipe and to determine the chemical, physical and sensory properties of the resultant product. Therefore, fiber at different levels of 10, 20 and 30% (w/w, flour basis) were used as a replacement of wheat flour in the cake recipe. Increasing the level of fiber resulted in the increase in hardness and cake volume. In addition, cake crust and crumb became darker. Cake hardness increased ,while cohesiveness decreased. Also cakes fiber had acceptable sensory characteristics. Finally, according to results of a general acceptance due to the average of the sensory properties, the samples contained 10% apple fiber, had the highest approval rating among the taste panelists. And according to the results of other tests, adding fiber to the level of 10% was acceptable and not significantly different from control samples.

Mazafati variety is one of the most important export products in Kerman province. Contamination with dirt, because of windy area and Transmission of fungal spores and other factors reducing the quality, are the most important problems to manufacturers. In this study, cleaning and covering of Clusters in the level of Khalaal were evaluated in four ograpHical directions to reduce pollution. Cleaning treatment was applied by pressurized air with a fan and acetic acid (0.4%). Coverings used on clusters were burlap, polyethylene fabric and 5% starch solution with nutmeg oil Hindi (4000 ppm). Effect of treatment was evaluated for a month during step conversion Khalall to Rotab Chemical tests include reducing sugars, total sugars, total soluble solids, Moisture, acidity, pH and Microbial tests including total count and counting microorganisms, mold and yeast. The results of the statistical analysis of data showed that the Brix, moisture content and pH in three types of cover compared to control were significant change (p≤0/01). Over time, the pH increased and acidity decreased in all treatments. The pH in the first week of sampling was 5.62 and in the fourth week were 6.95. During fruit ripening date, firmness also decreased significantly. Results showed that all three treatments with significant differences compared to control are superior in maintaining the properties of quantitative, qualitative and control of microorganisms and Preserved fruits on the tree. Sugar content in plots which were clean with fan was 39.8 that 36% increase compared to the control treatment but in Dates that were cleaned with vinegar 33.7% decreased. Most of PH (6.1) was observed in the polyethylene and starch covering treatments. Soluble solids in polyethylene covering treatment were 34.34. During fruit ripening, firmness also decreased significantly (p≤0/05). Cleaning and covering various treatments significantly decreases microorganisms in date compared to control. The number of microorganisms during the first three weeks of research did not significant increase but in the fourth week significantly increased which in this case also covers treatments and cleaning was superior compared to control (p≤0/01). The results obtained with nutmeg oil Hindi starch coating with polyethylene wrapping treatments than others in maintaining the properties of quantitative, qualitative and microbial recommended excels is the star turn.

In this work, a cold atmospheric pressure plasma was used as a low cost and non-thermal alternative method in food industry, and it was compared with traditional pasteurization method. Dielectric barrier discharge was used to generate the air plasma for the treatment of barberry juice, in 8, 10 and 12 minutes. The effect of the plasma treatment on the color, the amount of pH, total microorganisms, mold and yeast, lactic acid bacteria, acid resistant bacteria and Aspergillus niger were investigated and the results were compared with those by 12 min thermal pasteurization method. The results show that there are no meaningful statistical differences between the 8, 10 and 12 min plasma exposures and pasteurization methods, but there are meaningful differences between these samples and the control. It means that by optimizing such plasma device, the cold atmospheric plasma treatment is an appropriate alternative method for the thermal pasteurization.

Corn starch is widely used in different food products and many of these products contain salts. Therefore, in this study the influence of sodium chloride and calcium chloride (50,100, 150 and 200 mM) on water absorption, textural parameters, pasting properties and gel syneresis of corn starch was determined. The water absorption of starch was decreased by the increase of NaCl concentration. The texture measurements revealed that hardness, cohesiveness, gumminess and chewiness of starch gels were decreased while springiness was not changed significantly. Based on the RVA results, peak, breakdown, setback and final viscosities were decreased but the pasting temperature was increased by the increase of NaCl concentration. However, a reverse trend was observed in samples with CaCl2. Both salts increased the freeze-thaw stability of starch gels and the influence of calcium chloride was more obvious than sodium chloride.

There are different concentrate of glucose, fructose and asparagine in various varieties of potato. This is one of the most important reasons for production different amount of acrylamide during heat processing. In order to decrease acrylamide precursors, three methods, including: Blanching of potato slices (80ºC, 10, 15 min), Immersion of potato slices in L-asparaginase soluble (4, 8 ppm), Immersion of potato slices in acetic acid soluble (0.1, 0.5 mol/lit) were used in two potato varieties, Agria and Ladyrosetta. Then treatmented potato slices were fried at 180ºC and the amount of acrylamide in potato chips was measured. The results showed that, the effect of potato varieties and pretreatment method are significant on acrylamide production. According to the result, the sample of Agria variety that had been processed by 8 ppm L-asparaginase, had the minimum level of acrylamide but the highest level of it was observed in control sample of Ladyrosetta, and it had significant difference with other samples. Regarding to the result, Agria variety is more appropriate than Lady rosetta for potato chips producing. Furthermore, in order to reduce of acrylamide in final fried product, use of Lasparaginase is more effective than other methods.

Camelina (Camelina sativa) is an oilseed crop from the Brassicaceae family, which is rich in oil (28- 40%) and omega-3 fatty acids. This crop is able to grow in different climate and soil conditions, and compared to other oilseeds requires less water, fertilizer and pesticides. In this study, Camelina seeds (DH1025) were planted in Kermanshah, Kangavar and Sarpol-e Zahab, and then its oil properties were studied in detail. Through gas chromatography (GC) method, 13 different fatty acids were detected in the extracted oils. Four major fatty acids in all oil samples were linolenic acid (28.03-30.31%), linoleic acid (18.64-19.33%), oleic acid (15.44-18.36%) and eicosanoic acid (15.94-17.48%), respectively. Average amounts of iodine index, saponification value, specific gravity, refractive index and oil acidity of this crop were 143.5, 184.2, 0.915, 1.468 and 0.41 respectively and its 1000-seed weight were equal to 1.017. The oxidative stability of Camelina oil was 10.5 hours.

Proteins have different functional properties that geliing is one of the important properties. In current study, the effect of different concentrations of Basil seed gum (0, 0.05, 0.1, 0.3 and 0.5 %) on rheological properties of egg white albumin gel(4%) has been investigated. Result showed that apparent viscosity decreased by increasing of the shear rate. All samples showed shear thinning behavior. Basil seed gum free sample had 0.663 Pa.s viscosity at 501/s steady shear rate but viscosity increased while the gum content increased. Maximum viscosity was related to the sample include of 0.5% basil seed gum (5.32 pa.s). Tracking of hysteresis loops showed time dependency of all gel samples. Result of fitting data using different rheological models showed carreau model had maximum R2. Linear region assign about 1% using strain sweep test. Result of frequency sweep test showed loss modulus increased as frequency raised however this trend observed at low frequency of storage modulus. Storage modulus of sample including 0.1 and 0.5% basil seed gum was maximum at all of frequency rates and was minimum at sample free from basil seed gum. Loss modulus of this sample was the lowest value among all samples.

Fish oil is a rich source of omega-3 fatty acids, which is recommended for prolonged use due to beneficial nutritional effects and the prevention of heart disease and disorders. However, high unsaturation of this oil makes it susceptible to oxidation. In the present study, antioxidant activity of Origanum vulgare L. essential oil was evaluated by DPPH assay and its antimicrobial activity was determined by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Pseudomonas aeruginosa. Then, Origanum vulgare L. essential oil as natural antioxidant and alternative of synthesis ones, for stabilizing silver carp fish oil in water emulsion was used. So, after determining the fatty acid profile of the oil, different concentrations of the essential oil added to emulsion and stored at 4°C and 25°C and monitored in term of hydroperoxides, conjugated diene, conjugated triene and thiobarbituric acid. The results showed that 2400 ppm of Origanum vulgare L. had the most DPPH inhibitory power with 53.33% and MIC and MBC values of Origanum vulgare L. essential oil in gram-negative bacteria were more than gram-positive bacteria. Moreover, various concentrations of the essential oil prevented lipid oxidation of fish oil in water emulsions. So that, at 2400 ppm, had even better performance than synthetic antioxidant, TBHQ. Therefore, the natural Origanum vulgare L. essential oil due to its antioxidant and antimicrobial properties can be used as an alternative to synthetic types in various food systems.

In this study, a simple and sensitive colorimetric sensor towards pH changes for the detection of fish spoilage during storage at room and refrigeration temperature is presented. Colorimetric sensor was developed using Whatman filter paper No. 1 and water soluble anthocyanin pigments extracted from red cabbage. Fish spoilage was monitored based on anthocyanin color change in various pH. Microbial growth during storage and production of proteolytic enzymes resulted in protein degradation, accumulation of volatile amine compounds, increase in the pH and finally color change of anthocyanin-impregnated filter paper. Color change was measured using the CIELab method. The colorimetric sensor was validated by measuring total volatile basic nitrogen (TVB-N) levels, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and microbial populations in fish samples. Results indicated that the values of TVBN, pH, PV and TBARS increased with time of storage which was evidence of fish spoilage development. Also, the results were in accordance with color change of colorimetric sensor during storage and showed that proposed system enjoys a high sensitivity to pH variations. Therefore, the simple colorimetric sensor is capable to use in intelligent packaging.

Date is one of the important agricultural products in Iran and due to lack of attention to its by-products and its process; a large amount of this valuable product is annually lost. The aim of this study was to compare the physico-chemical, microbiological and sensory properties of ice cream with two sweeteners of date liquid sugar and date syrup. For this purpose, sugar was replaced with date liquid sugar and date syrup in ice cream formulation, at 5 levels (0, 25, 50, 75 and 100%). Chemical (sugar, fat, total solid, ash, acidity, protein, pH), physical (viscosity, over run, thermal shock resistance to melting, the shape retention and sensory (texture, taste, color, odor, general acceptation) and microbiological (aerobic mesophilic, E. coli, molds, yeasts and Staphylococcus aureus) properties were evaluated. The results showed that the microbial count of date syrup containing samples was reduced due to the anti microbial properties of date syrup. Over run and viscosity were similar to control samples in replacement levels up to 50% replacement by date liquid sugar and date syrup, but they decreased with further increase of replacement ratio (75 and 100%). By the increasing replacement ratio of date liquid sugar and date syrup, ice cream melting resistance and shape retention significantly decreased and sensitivity to thermal shock increased (P≤0.05). The results of the sensory properties showed that replacement in level of (25-50%) date syrup and (25-75%) of date liquid sugar had no significant effect on the organoleptic properties, and could be applied in ice cream formulation.

Starch is extensively used in food products which usually contain sugars. The functional properties of these productsare affected by the sugar used in their formulation. Therefore, in this project the effects of sucrose and glucose (0, 10, 20, 30 and 40% of dry starch weight)on water absorption, gel syneresis, pasting and textural properties of maize starch gels were studied. The results indicated that the water absorption of control sample was 8.70 which decreased to 5.99 and 6.70 for samples containing 40% sucrose and glucose respectively. Peak viscosity, breakdown, setback and final viscosity were decreased in the presence of sugarsand these effects were more obvious in higher sugar levels. The pasting temperature in maize starch lacking sugar was 65.55 and increased to 71.12 and 68.90 in the presence of 40% sucrose or glucose respectively.By the increase in sugar level textural parameters such as hardness, cohesiveness, gumminess and chewiness were reduced while springiness was not affected by sugar concentration.The syneresis of control starch gel after 5 freeze thaw cyclesreached 24% which significantly reduced to 10in the presence of sucrose and 14% in samples with glucose. Generally, in all the measured parameters the influence of sucrose was greater than glucose.

In this research, the effect of two methods of namely extraction (supercritical fluid) and traditional extraction (distillation with water) on the yield, chemical composition and antioxidant activity of essential oil of orange peel were studied. The whole process in the traditional method took longer than the new method and generally the yields of obtained essential oil by supercritical fluids (8.3%) was more than water distillation method (2.5%) respectively and chemical composition of essential oils was identified and the percentage of compounds was measured using gas chromatography- mass spectrometry. According to the results of chromatography, D-limonene which is the main composition of essential oil of orange peel had the highest frequency in both methods compared to the other components of the essential oil. But the amount of D-limonene in extractions by distillation method (86.58%) was more than supercritical fluids method (69.71%) respectively. However, according to the chromatogram, the amount of phenol in the essential oil of supercritical fluids (1.49%) was more than distillation method (0.03%), which is in accordance with the phenol comparison in the Folin-Ciocalteu test. Then the antioxidant activity of essential oils was evaluated using DPPH free radical scavenging methods and reducing ability. Finally, essential oil of supercritical fluids, showed a higher antioxidant activity than water distillation. In other words, the lowest IC50 (the highest antioxidant activity) is equal to 35.98 mg/ml in DPPH method of supercritical fluid extraction method.

Grape with high annual production and short shelf life has a lot of wastes post harvest. In order for optimal use of precious properties of grape and balancing the market and increasing the value added of grape, it is necessary to develope the processing methods and producing new products for decreasing wastes. The aim of this research was production of semi-solide grape molasses with spreadable texture and suitable physical, chemical and sensory properties. Several studies have been carried out to evaluate consistency and firmness in different foods with hydrocolloid compounds. Two different types of grape molasses (Kashmar and Quchan) were used. In order to produce semi solide grape molasses, some hydrocolloid compounds such as carboxy methyl cellulose (2 levels, 0.5 and 1%), Pectin (2 levels, 1 and 2%), Guar (2 levels, 1 and 2%) and their mixtures were used. The experimental design was performed as factorial test in complete randomized design with 3 replications. The results showed that the samples with 2% guar, had undesirable texture and taste, therefore were not accepted by panelists. The samples with 0.5 % carboxy methyl cellulose had the best sensory properties, consistency and texture. The panelists preferred Kashmar grape molasses for using Askari grape variety, its more suitable taste, higher brix and processing procedure. Kashmar grape molasses gained higher point.