Showing 31 results for Motamedzadegan
, Masoud Rezaei, Saber Khodabandeh, Ali Motamedzadegan, Mehrdad Norozinia,
Volume 5, Issue 1 (6-2016)
Abstract
The response surface methodology was employed to optimize the effects of pH, temperature (˚C), time (min) and the ratio of enzyme to substrate (% of substrate) on the hydrolysis process of cuttlefish muscle by alcalase. Central composite rotatable design with 5 levels and 4 factors and α=2 was used for the optimization of the process to gain the highest degree of hydrolysis. pH, temperature, time, enzyme concentration, interaction of temperature-enzyme concentration, square of pH, temperature, time and enzyme concentration had significant effects on the process. The R2 = 0.95, lack of fit < 0.05 and adeq-Precision of 14.16 for the model showed that the model could explain the variability within the range of values. The optimum condition for 42.0117 % of degree of hydrolysis was determined by Design Expert as pH 8.19, temperature 50.23, time 129.62 and enzyme2.15%.
M. Esmaeili Kharyeki , M. Rezaei, S. Khodabandeh , A. Motamedzadegan,
Volume 7, Issue 1 (Winter 2018)
Abstract
Aims: Skipjack tuna has the highest level of catch rate among tuna all over the world. Its head contains about 64% protein. Many Protein Hydrolysates and peptides obtained from various marine sources have a high antioxidant power. The aim of this study was to investigate the antioxidant activity of Protein Hydrolysate in Skipjack tuna head.
Materials & Methods: In this experimental study, 30 Skipjack tunas were investigated. At first, the amount of different compounds (protein, fat, ash, and moisture) was evaluated in the raw material; then, the hydrolysis process was performed by Alcalase enzyme and the hydrolysis degree of the protein hydrolysate was evaluated at different times. The antioxidant activity of the protein hydrolysate mixture was measured by DPPH radical scavenging activity, iron revival power, and ABTS radical inhibitory activity. For data analysis, the analytical tests were used.
Findings: The main part of the fish head was protein and it had high levels of ash. The degree of hydrolysis increased with increasing time and was it significant at 15, 60, and 120 minutes (p<0.05), but not significant at 120 and 240 minutes (p<0.05). DPPH radical scavenging activity increased with increasing hydrolysis time and there was a significant difference in all samples obtained from different times (p<0.05). The iron reduction capacity of the protein hydrolysate samples increased with increasing the hydrolysis time, and the highest amount was at 240 minute. The samples obtained from different times had a significant difference in iron reduction capacity (p<0.05). Increasing the concentration of protein hydrolysate increased inhibitory activity (p<0.05).
Conclusion: Protein hydrolysate in Skipjack tuna head has a high antioxidant activity and can be used in food products to increase oxidation stability.
Mohammad Kazem Mirzakhani, Abdolmohammad Abedian Kenari, Ali Motamedzadegan,
Volume 8, Issue 2 (Spring 2019)
Abstract
- In this study, the apparent digestibility of protein and amino acids of ten types of plant and animal feed ingredients as the main sources of protein was evaluated in Siberian sturgeon diet (290-250 g).
Materials and Methods: Feedstuffs included fish meal, meat and bone meal, poultry byproduct meal, blood meal, feather meal, soybean meal, rapeseed meal, wheat gluten, corn gluten and bakery yeast. The dietary treatments included: reference diet and ten different experimental rations (30% of the target feed ingredient + 70% of the reference diet). Chromic oxide was used as an indigestible marker in dietary feed. A group of 165 Siberian sturgeons stocked into 33 tanks with 500 liters volume and fed with test diets (3 replicates per diet).
- At the end of the experiment, the highest and lowest protein digestibility was observed in fish meal (92.87%) and poultry byproduct meal (59.96%), respectively. Also, the highest level of amino acid digestibility in fish meal was measured (90.9% and 88.13% for total essential and non-essential amino acids respectively). The lowest digestibility of the essential amino acids was observed in rapeseed meal (65.5%) and non-essential amino acids in poultry powder (60.68%). Conclusion: Based on the results of the present study, fishmeal, meat and bone meal, poultry byproduct meal, corn gluten and wheat gluten were identified as feed ingredients with high protein and amino acids digestibility for Siberian sturgeon.
Volume 11, Issue 2 (Spring 2020)
Abstract
Diabetes mellitus is a major health problem in the worldwide. Inhibition of DPP-IV is one of the methods to control diabetes type 2. Inhibition of this enzyme may improve glycemic control in diabetics by preventing the rapid breakdown and there by prolonging the physiological action of incretin hormones. Furthermore, improving the antioxidant system in diabetic patients can prevent the occurrence of secondary disease caused by oxidative stress. Therefore, the head of skipjack tuna was hydrolyzed with alcalase enzyme (1/5% of raw material weight) for 4 hours, in order to produce a product with antidiabetic and antioxidant activities. The DPP-IV inhibition activity, DPPH radical scavenging activity and reducing power of hydrolysate were measured. The results showed that the skipjack tuna head protein hydrolysate possess bioactive properties in a concentration dependent manner and increasing the protein concentration leads to a significant increase in bioactive properties of hydrolyzed product (p≤0.05). The IC50 of protein hydrolysate in DPP-IV inhibition and DPPH radical scavenging activities were obtained 1.016±0.02 mg/ml and 0.297±0.015 mg/ml, respectively. Also the reducing power of hydrolysate was 0.176±0.002 in 2.5 mg/ml protein concentration. Overall, according to the obtained results, it can be concluded that protein hydrolysate of skipjack tuna head possess high antioxidant and antidiabetic activities in vitro, and can be used as a food additive to enhance health level if additional research be conducted.
Volume 12, Issue 47 (7-2015)
Abstract
The effect of the addition of various gelatin with different gel strength and changes in total solid non-fat on physicochemical and textural properties of non-fat yogurt evaluated, and addition of high bloom (HBG) and low bloom (LBG) gelatin in different concentrations (0.25%, 0.5%, 0.75% and 1%) impacts on textural properties of yogurt compared. According the results during gel formation and after that, gelatin interacted with milk casein network, as basis of the yogurt gel structure and revival water bands, thereupon plummet syneresis dramatically specially in samples with higher gelatin amount. On the other hand textural properties such as gel firmness of yogurt hardly affected by gelatin and SNF content; and samples contain 12.5% SNF and 1% HLB had firmest gel. Also, viscosity increased with addition of gelatin and solid nonfat. This feature can reduce the deficiencies of fat removed
Volume 14, Issue 62 (4-2017)
Abstract
The present research work was aimed to evaluate the effects of whey protein concentrate (WPC) at different levels of 0, 2, and 4%, as a protein based fat replacer, soy protein isolate (SPI) (0, 1, and 2%) and microbial transglutaminase (MTG) (0, 1, and 2%) on some physical properties of a low fat vanilla ice cream (4% fat). Electrophoresis pattern of ice cream proteins and effect of MTG on proteins were analyzed by SDS-PAGE. Total solids of all formulations was adjusted on 34%. Results showed that application of WPC in formulation of low fat ice cream significantly increased hardness and melting values, while SPI significantly (P<0.01) increased hardness and reduced melting value. MTG decreased hardness and melting of ice cream samples compared to the control (P<0.01). Results showed that application of MTG in low fat ice cream was more useful than the utilization of SPI and WPC in terms of hardness and melting properties.
Volume 15, Issue 77 (9-2018)
Abstract
Volume 16, Issue 86 (4-2019)
Abstract
Nowadays, modifying of the functional properties of proteins by proteolytic enzymes is a novel way in order to use the hydrolysates as a natural antioxidant, emulsifier or foaming agent. In this study, TSP was hydrolyzed by commercial trypsin (porcine), trypsin extracted from Caspian Kutum, pepsin, alcalase and papain. The results showed that the highest degree of hydrolysis (DH%) was related to commercial trypsin (19.34 %), Alcalase (16.04%) and Kutum trypsin (14.29%), respectively. The highest emulsifying capacity was obtained by commercial and Kutum trypsin, compared to non-hydrolyzed protein, and Alcalase hydrolysates had the highest emulsion stability (p <0.05). Higher foaming capacity was observed in hydrolysates by commercial trypsin, followed by Kutum trypsin, compared to non-hydrolyzed protein. However, the lowest value was related to Alcalase. In the case of foam stability, the commercial trypsin hydrolysate had the most stable foam, while Kutum trypsin, despite its lower efficiency compared to commercial trypsin, had the second place. Hydrolysates prepared with Kutum trypsin had the highest DPPH-scavenging ability and reducing power but the lowest OH-radical scavenging power. The results of this study show that kutum trypsin can produce soy protein hydrolysates with good functional and antioxidant properties, which are comparable to commercial enzymes.
Volume 16, Issue 91 (September 2019)
Abstract
This study was investigated whit aimed to the effect of unsaponifiable matter (USM) of Tarom rice bran oil on free and nano-encapsulated form in oxidative stability of soybean oil. For this purpose nanoencapsulation of USM by chitosan and Lepidium perfoliatum seed gum (LPSG) as wall material were performed and particle size, encapsulation efficiency and also antioxidant activity before and after nanoencapsulation were measured. The effect of free and nano-encapsulated forms and synthetic antioxidant TBHQ on oxidative stability of soybean oil were evaluated by peroxide value (PV), conjugated dien (CD), thiobarbituric acid (TBA) and color index and also release of phenolic and tocopherol compounds were measured. The results of this study showed that the nano-encapsulated sample by LPSG had particle size and encapsulation efficiency higher than that of the nano-encapsulated sample by chitosan, and also the antioxidant activity of USM decreased after nanoencapsulation. In the study of oxidative stability of soybean oil, our results showed that in the early stages of storage, USM of rice bran oil and nano-encapsulated samples increased the oxidation rate of soybean oil, but further free USM has shown better antioxidant activity compared to nano-encapsulated samples, and nano-encapsulated sample by LPSG had better antioxidant activity than the nano-encapsulated sample by chitosan. However, the synthetic antioxidant TBHQ showed higher antioxidant activity and better performance.
Volume 16, Issue 92 (october 2019)
Abstract
In food products based on foam system, stability is important. Therefore, in this study the effect of four types of local gums (basil, cress, wild sage and lepidium perfoliatum seed) in three different concentrations (0.5, 1 and 1.5%) on foam stability and also different concentrations of egg white albumin (1, 2 and 3%) as a foaming agent on the physical properties of celery juice foam were evaluated and then the best foam type (minimum density, minimum drainage volume and maximum overrun) was selected. The results showed, samples containing 1.5% cress seed gum, 1% Lepidium perfoliatum seed gum, and 0.5% wild sage seed gum, had the best physical foam properties at the concentration of 1, 2 and 3% albumin, respectively. After comparing the means of the best selective samples at each level of the protein concentration (1, 2 and 3%), The sample containing 0.5% wild sage seed gum and 3% albumin, was chosen as the best sample with the lowest density (0.210 g / cm3), the highest overrun (327%) and the lowest drainage volume (0 ml), and this sample can be used in some process namely foam mat drying.
Volume 16, Issue 92 (october 2019)
Abstract
The foam mat drying is a process in which liquid food is converted in to stable foam by combining gas into it, and then dried at a relatively low temperature. The effect of drying temperature (50, 60 and 70 °C) and thickness (4 and 8 mm) on foam mat drying kinetics of shrimp under hot-air drying was investigated. The drying curves obtained were processed for drying rates to find the most convenient model among the 12 different expressions proposed by earlier authors. In addition, the various statistical parameters such as: R2, reduced chi-square, SSE and root mean square error (RMSE) were used to determine the quality of the fit. The colour change during concentration processes was investigated. Total colour differences parameter was used to estimate the extent of colour loss. The zero-order, first-order and a combined kinetics model were applied to the changes in colour parameters. Based on the results, Midilli model was found to be the best model fitted to the experimental hot air drying data at all temperature levels. These models exhibited the highest value of R2 and the least RMSE, χ2 and SSE comparing to the other models. Results indicated that variation in TCD followed combined kinetics model. This model implied that the colour formation and pigment destruction occurred during foam mat drying process of shrimp.
Volume 16, Issue 92 (october 2019)
Abstract
Cluster analysis (CA) is a multivariate tool used to organize a set of multivariate data (observations, objects) into groups called clusters. The cluster analysis method was carried out on characteristics of Ricotta cheese powder, with the effect of milk/whay ratio (formulation) and foam mat drying temperature. In this study, 4 types of formulations and 6 drying temperature were used to study the density, hygroscopic and color factors to find the formulation and optimal temperature that created the proper physical properties. The results of analysis of variance showed high temperature due to higher vapor velocity, decreased density and increased hygroscopicity (p<0.05). Also, with increasing temperature, the index "L" decreased and the indices "a" and "b" decreased. According to the results of cluster analysis, cluster 2 was selected as the best cluster for the least disparity between treatments and also due to the lowest Within-group variance. In this cluster, cheeses with a high percentage of whey in the formulation combination and low temperatures are found to foam mat drying. According to the results, the Lightness (L) of the powders of this cluster is higher, and at lower temperatures the density and hygroscopy are lower. Based on the results in general, the use of cluster analysis to select formulations for foam mat drying of ricotta cheese is a suitable method.
Volume 16, Issue 93 (November 2019)
Abstract
In current study, the effect of different hydrocolloids as stabilizer (high bloom gelatin (HBG), low bloom gelatin (LBG), cold water fish skin gelatin (FSG), low methoxyl pectin (LMP) and modified tapioca starch (MS)), was investigated on physicochemical and rheological properties of yogurt in four concentrations. The results showed that in all samples, except pectin, PH decreased over time, but pH reduction in the sample containing modified starch (MS), was significantly higher than other samples. The LMP sample and the HBG sample had the lowest and highest water holding capacity (WHC) with 57 and 78.6 percent respectively. At low concentrations, the stabilizers produced loose tissue in yogurt, but at high concentrations all types of gelatin improved the uniformity of yogurt tissue. The highest tissue consistency was observed in the HBG sample. Also, viscosity of the samples increased with the addition of stabilizers, and there was a significant relationship between stabilizers concentration and viscosity. All of types of gelatin decreased number of grains but starch significantly increased graininess in all concentrations (p<0.05). However FSG showed the best effect and decreasing of graininess.
Volume 17, Issue 98 (April 2020)
Abstract
The purpose of the present research was to investigate four commercial cultivars of tomato (Karoon, 3402, LS0019 and H1015) in order to determine the physicochemical attributes of the cultivar. During this investigation, fruit qualities were evaluated: Soluble solids, total solids, and moisture, pH, lycopene, β-carotene, lutein, and β-cryptoxanthin contents, color indexes (CIE a* b* L*), hue angle (h), chroma (C), total polyphenols and antioxidant activity.The amounts of total solids, a*, b*, L*, carotenoids (lycopene, β-carotene, lutein, β-cryptoxanthin), total polyphenols, and antioxidant activity (Free radical scavenging capacity, reducing power, total antioxidant capacity) remained significantly different among the investigated cultivars (p<0.05). The results showed that the H1015 cultivar had the highest antioxidant activity and carotenoids content especially lycopene. Moreover, this cultivar had the best color indexes (highest a*) in comparison with the other cultivars, it is concluded that the H1015 cultivar is comparable to other cultivars and thus is recommended for cultivation and processing.
Volume 17, Issue 106 (December 2020)
Abstract
β_glucan is dietry fibre and soluble gum and .it has various physical properties such as thickening,stabilizing, emulsification, and gelation.in this study the effect of intensity (0,200, 300, 400watt) and time (0, 3.5 and 7minute sultrasonic waves were investigated on the physicochemical and the rheological properties of extracted.ß_glucan.The results showed that ultrasound intensity and time on moisture, ash, protein, starch and β-glucan content were significant (P <0.05), While it was not significant on fats and fibers (P >0.05), The sample with the intensity of 200 watts in 3.5 minutes showed the highest amount of β-glucan (77.1%) and the sample at 400 watts in 3.5 min with the lowest amount of ß-glucan (55.6%).Result showed that apparent viscosity decreased by increasing of the shear rate. All samples showed shear thinning behavior.The highest consistency coefficient, zero shear viscosity and lowest flow index was controlsample., and the lowest consistency coefficient and zero shear viscosity and the highest flow index was in the sample with 400 W intensity for 3.5 min. The results obtained from fitting the data with different rheological models showed that the Herschel andCarreau model was chosen for the best model. Linear region assign about 0.5 %using strain sweep test. Result of frequency sweep test showed first, by increasing the frequency of both the modulus of loss and storage , the storage modulus was reduced at high frequencies. The control sample was at low frequency G²>G, at high frequency G¢>G², Other examples were G¢>G².
Volume 17, Issue 106 (December 2020)
Abstract
Ultrasound is used as a physical method to modify the functional properties of starch. In this study, the effect of ultrasound at 25, 45 and 65°C on the some rheological properties corn starch paste in the presence of Arabic gum was investigated. Results showed that the amylose leakage increased with increasing temperature; but in the presence of Arabic gum, amylose leakage decreased. Sonicated samples showed lower paste clarity. Clarity decreased with increasing temperature; but in the presence of gum arabic the clarity was increased. Clarity changes were lower in the presence of Arabic gum. The least gelling concentration (LGC) was higher in ultrasonic samples and also LGC was higher in the Arabic gum contained samples. Ultrasonication and Arabic gum reduced the maximum and final viscosity of starch paste. Sample sonicated at 45ºC was selected the best sample with minimum amylose content and showed the less changes clarity, higher LGC, minimum final viscosity. The presence of Arabic gum and the ultrasonic temperature are the important parameters that influenced the modification of starch properties.
Volume 17, Issue 109 (March 2021)
Abstract
ß-glucans are non-starch polysaccharides and water soluble hydrocolloids, Apart from being nutritionally important, ß-glucans show an important technological role as thickening, stabilizing, emulsification, gel-forming component and fat substitute in the dairy products, bakeries, meats, pharmacy, cosmetics, and chemical industries, and feed production. The extraction of cereals ß-glucans is very difficult. Ultrasonic extraction, represents higher efficiency since this method is a cost- effective which shortens the extraction time ,energy and solvent consumption compared to conventional methods..in this study the effect of intensity and time at four different powers (0, 200, 300, 400 w) in three time (0, 3.5 and 7 min) intrevals were investigated on the yield, recovery, color and the functional properties of extracted ß-glucan.The results showed that the intensity and time of ultrasound were significant on yield, recovery, color, emulsion stability, water holding capacity, solubility ß-glucan (p<0.05). With increasing ultrasonic intensity and time, extracted ß-glucan yield, recovery, emulsion stability, water holding capacity increased. The highest extraction yield (3.34%), solubility (75.67%) were observed at power 400w for 7 minutes, Also the highest recovery (52.04%), emulsion stability (69.06%), water retention capacity (13.21 g /g), compared to blank sample at power 300w for 7 minutes . L* , a*and b* and were 76.66, 3.2, 3.2 respectively.
Volume 18, Issue 112 (May 2021)
Abstract
Chitosan based films have several disadvantages, such as poor mechanical properties and low moisture deterioration, which limits their use in food packaging. In this study, nanomaterials such as nanoclay (M) and nanosilver (Ag) were used to improve the properties of the film whilst applying electrical current during film drying. Nanocomposite films based on chitosan, were prepared by adding four levels 0, 1, 3 and 5% silver and clay, then heat and electricity with 0, 15, 30 and 60 Voltage were simultaneously applied to dry them, finally their characteristics like including WVP, O2P, physical and mechanical properties, and microstructure were studied. The presence of nanoparticles in nanocomposite films increased the moisture, thickness, opacity, WVP, O2P and improved mechanical properties, incomparison with pure chitosan film. On the other hand, the concentration of 3% in both treatments improve the permeability and mechanical properties of the 1 and 5% levels. The application of electrical current had no significant effect on moisture content, solubility and thickness. In contrast, the use of electric current with a voltage of 30, improved mechanical properties, turbidity and WVP and a voltage of 60, improved O2P in nanocomposites. The images produced by the SEM show that the pure chitosan film has a rough surface and multiple gaps and the film surface of the nanoclay is relatively smooth and compact, which allows for increased tensile strength and inhibitory properties. The film containing nanosilver also had a more turbulent structure with a gap, turbidity and mechanical properties, and less inhibitory properties than nanoclay.
Volume 18, Issue 113 (july 2021)
Abstract
In this study, the effect of basil and cress seed gum concentrations (0.00, 0.25, 0.50, and 1.00 % w/w) were individually investigated on the rheological, color, and textural properties of the fresh paste gel samples. The mixture of fresh fish paste and various concentrations of gum were heated at 75 °C for 30 minutes to obtain heat-induced gels. The strain test results showed that the elastic properties (storage modulus) of the gel samples at low frequency were higher than their plasticity properties (loss modulus), while they crossed over each other in the middle of the strain range. The Gchr('39')LVE, G "LVE, Υ c, and Ƭf parameters of the gel samples reduced with increasing gum concentration compared with the control sample. The obtained data by the frequency sweep test is nicely fitted by the Power Law Model. Also, the results of the frequency test at low frequencies showed solid-like behavior for all gel samples, while at higher frequencies the loss modulus and the storage modulus increased. This behavior can be related to the weak structure of gels. The temperature sweep test showed that the values of Gchr('39') (storage modulus) and G" (Loss modulus) for the mixture of samples decreased gradually with increasing temperature, and increased with decreasing temperature. The texture profile analysis showed that the type and concentration of gum significantly (p <0.05) affected the hardness, elasticity, and cohesiveness of the samples. Results of the puncture test showed that the gel strength of the samples changed significantly with the concentration and type of gum. As the concentration of gum increased, the strength of the gel decreased and the intensity of the decrease was greater in the type of cress gum. The type and concentration of gum affected significantly the yellow and red index of the sample of fish pastes
Volume 18, Issue 115 (September 2021)
Abstract
Producing of fish powder is a good way for increasing the shelf life of these valuable protein sources, easy accessing and increasing of food variety.In this study, the effect of drying temperature on physicochemical properties of kilka and carp fish powder was investigated. For this purpose, temperatures of 45, 55, 65 and 75 °C were used to dry the fish. The results of this study showed that moisture, fat, protein and TVN for carp powder was 7.02%, 4.92%, 83.80%, and 150 mg/g, while moisture, fat, protein and TVN of kilka fish powder was 8.12, 8.8%, 5.09%, 82.18% and 140 mg/g, respectively. The highest water binding capacity was related to dried carp samples at 45 °C and dried kilka at 55 °C. The lowest and highest fat reabsorption was in dried carp samples at 45 °C and dried kilka at 55 °C, respectively. The results of density test showed that with decreasing drying temperature, the density of the final powder decreased. The highest densities of carp and kilka powders were 0.511 g/cm3 and 0.408 g/cm3, respectively, which were dried at 45 °C. The study also represented that with increasing temperature from 45 to 75 °C, L* factor of the powders decreased. Besides, scanning electron microscopy (SEM) results indicated that the proteins were more denatured at higher temperature and the particle sizes were reduced.
