Research Article
Ali Taheri; Abdolmohammad Abedian Kenari; Ali Motamedzadegan; Mehran Habibi Rezaie
Abstract
Protein hydro-lysate was prepared from Gold striped sardine (Sardinella gibossa) by Papain. Hydrolysis conditions (time, temperature, and enzyme activity) were optimized by response surface methodology (RSM) using a factorial design and anti-oxidative activity was the dependent variable. Results of the ...
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Protein hydro-lysate was prepared from Gold striped sardine (Sardinella gibossa) by Papain. Hydrolysis conditions (time, temperature, and enzyme activity) were optimized by response surface methodology (RSM) using a factorial design and anti-oxidative activity was the dependent variable. Results of the total determination coefficient, adjusted R2 and predicted R2 indicating the validity of prediction model and the experiment error was very small. An enzyme activity to substrate ratio (X1), 2%; time (X2), 30 minute, and temperature (X3), 45 °C were found to be the optimum conditions for a higher DPPH free radical scavenging activity (64.5%), using Papain. According to amino acid analysis results and chemical score, methionine and Isoleucine were the limiting amino acids in the hydro-lysate. The protein hydro-lysate tends to be a functional additive in food industries.
Research Article
Abbas Ahmadi; Seyed Ali Mortazavi; Elnaz Milani; Reza Rezaeemokaram
Abstract
In this study, frozen yoghurt was produced as a synbiotic product. A food product containing both probiotics and prebiotics is named as synbiotic or functional food. Lactobacillus acidophilus (La-5) as a probiotic bacteria was added to frozen yoghurt in two types; free and encapsulated, and its survivability ...
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In this study, frozen yoghurt was produced as a synbiotic product. A food product containing both probiotics and prebiotics is named as synbiotic or functional food. Lactobacillus acidophilus (La-5) as a probiotic bacteria was added to frozen yoghurt in two types; free and encapsulated, and its survivability was evaluated during 60 days storage at -18 °C . Also Fructo-oligosaccharide as a prebiotic compound was used for producing frozen yoghurt in different levels (0%, 0.4% and 0.8% (w/w)). The viable cell number in free state in samples with (0%, 0.4% and 0.8% (w/w)) Fructo-oligosaccharide was 3.8×109 cfu/ml, 3.5×109 cfu/ml and 3.8×109 cfu/ml and after 60 days of storage these numbers were decrease to 2×107 cfu/ml, 2.2×107 cfu/ml and 2.2×107 cfu/ml respectively. Whereas in encapsulated state, the viable cells in samples with (0%, 0.4% and 0.8% (w/w)) Fructo-oligosaccharide these numbers was 7.5×109 cfu/ml, 8.9×109 cfu/ml and 9.8×109 cfu/ml and after 60 days, these numbers were decreased to 2.13×109 cfu/ml, 2.5×109 cfu/ml and 2.9×109 cfu/ml.The results indicated that encapsulation of L. acidophilus could significantly (p
Research Article
Homa Baghaei; Farimah Aghaei; Nasser Sedaghat; Mohebbat Mohebbi
Abstract
In view of the importance environmental pollution caused by plastic food packaging, in recent years there is a considerable interest in edible films and coating based on polysaccharides, proteins, lipids or combination of them. Edible coatings also serve as carriers of food additives such as anti-browning ...
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In view of the importance environmental pollution caused by plastic food packaging, in recent years there is a considerable interest in edible films and coating based on polysaccharides, proteins, lipids or combination of them. Edible coatings also serve as carriers of food additives such as anti-browning and antimicrobials agents, colorants, flavor, nutrients and spices, so act as active packaging. In this study, effect of garlic essential oil )0.5%, 1.5%, 2.5% w/w of film solution) on isolated soy protein films was investigated by measuring changes in properties including antimicrobial activity against (Escherichia coli H7:0157, Salmonella enteritidis and Staphylococcus aureus), mechanical (tensile strength, elongation at break), physical (transparency, water vapor permeability, microstructure) and sensory (chewing, apparent and odor). Incorporation garlic oil improved mechanical and water vapor permeability properties and decreased transparency, structure and organoleptic attributes (p
Research Article
Reza Farhoosh; Mohammad Hossein Hadad Khodaparast
Abstract
In the present study, the oxidative stability of nine Iranian commercial olive oils, including four virgin samples and five deodorized ones, was compared to that of two foreign virgin olive oils. In total, the foreign samples had the MUFA/PUFA ratios (av. 9.27) higher than those of domestic ones (av. ...
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In the present study, the oxidative stability of nine Iranian commercial olive oils, including four virgin samples and five deodorized ones, was compared to that of two foreign virgin olive oils. In total, the foreign samples had the MUFA/PUFA ratios (av. 9.27) higher than those of domestic ones (av. 5.70). The peroxide and acid values of the olive oils studied ranged from 8.5 to 14.5 meq/kg and from 0.1 to 4.27 mg/g, respectively. Tocopherols content of the foreign olive oils (av. 436.7 ppm) was averagely higher than that of the domestic olive oils and even about two times that of domestic virgin ones (223.4 ppm). On average, the foreign virgin olive oils contained phenolic compounds (154.0 ppm) higher than that of the domestic ones (112.3 ppm) and especially deodorized olive oils (46.0 ppm). The oxidative stability of oil samples was suitably interpreted in terms of chemical composition data, so that the foreign virgin olive oils had more appropriate chemical composition in total, and therefore, indicated oxidative stabilities higher than those of the domestic virgin and deodorized olive oils.
Research Article
Zahra Izadi; Ali Nasirpour; Ghasem Ali Garoosi
Abstract
Phytosterols have been used for reduction of cholesterol since 1950. The high melting temperature and chalky taste are the major problems related to the enrichment of foodstuffs with phytosterols. The Cristal construct of these compounds could not reduce remarkably the blood cholesterol in comparison ...
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Phytosterols have been used for reduction of cholesterol since 1950. The high melting temperature and chalky taste are the major problems related to the enrichment of foodstuffs with phytosterols. The Cristal construct of these compounds could not reduce remarkably the blood cholesterol in comparison with the fatty soluble forms. Presence of free and alcoholic forms of phytosterols and also their capability in making strong linkage with nutritional matrix make difficult and complicate their analysis and distribution quality in foodstuffs. In this study the emulsion include the emulsifier, soy bean oil and water was used for dissolving and dispersing of phytosterols in water phase. Then the distribution state of phytosterol in enriched yogurt was investigated using Gas Chromatography. Because of the appearance and color are the first parameters in the evaluation of nutrition materials, digital imaging and Photoshop software was used to measure the color of enriched yogurt. Results indicated that the using of emulsifier and soy bean oil could be suitable approach to disperse and dissolving phytosterol in liquid phase. Gas Chromatography showed that it is a favorite method to measure manner of dispersing the phytosterol. In the colorimetric studding no significant differences observed between enriched yogurts and control. Also result exhibited that the using of Photoshop software could be the better scale in comparison with the other current method and instruments for color assay of the yogurt.
Research Article
Marjaneh Alinejhad; Bahareh Shabanpour; Reza Safari; Mozhgan Alinejhad; Hassan Nasrollahzadeh Saravi
Abstract
The objective of this study was to produce fish peptone from tuna (Thunnus tonggol) viscera, by Alcalase. Response Surface Methodology (RSM) was employed for optimizing the temperature and pH. Hydrolysis was done in different tempratures (50-65˚C) , pH (8-8. 5) and selected 13 treatments. Samples with ...
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The objective of this study was to produce fish peptone from tuna (Thunnus tonggol) viscera, by Alcalase. Response Surface Methodology (RSM) was employed for optimizing the temperature and pH. Hydrolysis was done in different tempratures (50-65˚C) , pH (8-8. 5) and selected 13 treatments. Samples with higher value of protein were used instead of the standard peptones which applied in commercial media for Listeria monocytogenes. Based on the three-dimensional graphs, the optimum condition for temperature and pH were determined to be 50˚C and 8. 5 respectively. The results showed that the highest (76. 89 g/l) and the lowest (38. 54 g/l) rates of protein content were related to pH 8 at 57˚C and pH 8 at 50˚C. Maximum bacterial growth rate was related to pH 8 at 65˚C. Results also showed that tuna (Thunnus tonggol) viscera can be used as low cost nitrogen sources for Listeria monocytogenes growth media.
Research Article
Shahla Khodabakhsh Aghdam; Mahdi Moradi; Alireza Yousefi
Abstract
In this research, Papaya slices with dimensions of 0.5×2×5 cm3 were dried at 45 °C using a cabinet dryer in which drying air velocity and relative humidity were 0.9 m/s and 30%, respectively. The moisture diffusion coefficient of Papaya was determined in this drying condition. Mass transfer equation ...
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In this research, Papaya slices with dimensions of 0.5×2×5 cm3 were dried at 45 °C using a cabinet dryer in which drying air velocity and relative humidity were 0.9 m/s and 30%, respectively. The moisture diffusion coefficient of Papaya was determined in this drying condition. Mass transfer equation with its boundary conditions was solved based on finite difference method. Finally, coefficient of determination and goodness of fitting between the gained theoretical model by solving mass transfer equation, and experimental data were obtained R2=0.996 and RMSE=0.00115. Therefore, finite difference numerical method showed a suitable correlation with low error into the experimental data for solving of mass transfer equation.
Research Article
Hoda Khalesi; Mohammad Alizadeh khaled abad; Mahmoud Rezazadehbari
Abstract
Zedo gum is a polysaccharide that exudates from Amygdalus scoparia Spach tree. In this study the apparent viscosity under the influence of the gum concentration (0.5%, 0.75%, 1%, 2%, 3%, 4% and 5% w/v), temperature (20, 45, and 70 ˚C), pH (2, 5 and 8) and salt concentration (0-0.5 M) has been investigated. ...
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Zedo gum is a polysaccharide that exudates from Amygdalus scoparia Spach tree. In this study the apparent viscosity under the influence of the gum concentration (0.5%, 0.75%, 1%, 2%, 3%, 4% and 5% w/v), temperature (20, 45, and 70 ˚C), pH (2, 5 and 8) and salt concentration (0-0.5 M) has been investigated. Zedo gum is composed of soluble and insoluble components that respectively have the properties of solubility and swelling in water. The apparent viscosity changed due to temperature and pH. The highest viscosity was obtained at pH of 7.2 and 24 ˚C. Viscosity was changed by addition of certain strong electrolytes. The emulsion capacity and stability of oil in water emulsion increased by increasing gum concentration. Thermal behavior of Zedo gum with different moisture content was studied by differential scanning calorimetry (DSC). Thermal profiles showed an endothermic event. Considering the results obtained, Zedo gum is a potential natural and domestic additive for industry as a thickening agent, emulsifier and stabilizer.
Research Article
Mehdi Jalali; Esmaeil Atayesalehi; Mohammad Hossein Hadad Khodaparast
Abstract
Of a large amount of date palms cultivated and harvested in Iran, only about 11 – 12 annual percent is used in food processing and packaging industries. Due to the poorq uality of produced dates, it is regarded as waste and is mainly used as feed stocks. Thus, through producing syrup and liquid sugar ...
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Of a large amount of date palms cultivated and harvested in Iran, only about 11 – 12 annual percent is used in food processing and packaging industries. Due to the poorq uality of produced dates, it is regarded as waste and is mainly used as feed stocks. Thus, through producing syrup and liquid sugar from date palm of low quality could be regarded as a new opportunity to convert waste dates to a higher value product in order to reduce imports of similar products and also to export it in large quantities. In the present study, the face-center central composite design of response surface methodology was used to investigate the influence of temperature (60-80 °C), pH (4-7), time (1-5 h) and water-to-date pulp ratio (1:3-1:5) on yield and absorbance of Juice extraction from grade II date of the Kaluteh variety and its optimization. The results revealed that all the investigated independent variables have significant influence on the process, but the effect of time was not significant on the absorbance. Also, the main influencing parameter on the extraction process of palm was observed to be the water-to-date pulp ratio. The results showed that the extraction yield increased at elevated temperatures, higher mixing ratios, longer times and lower pH, whereas increasing temperature and decreasing pH had a negative impact on clarity of syrup. The optimum conditions obtained for the extraction process were temperature of 77.45 °C, time of 5 h, mixing ratio of 1:4 and pH= 4. At the optimum conditions, the yield and absorbance were found to be 62.5 % and 0.28, respectively.
Research Article
Sanaz Ojnordi; Majid Javanmard; Simin Asadollahi
Abstract
Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been ...
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Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been studied in the current research. In this paper, the simultaneous effect of coating with whey protein and Zataria multiflora Boiss extract on the quality of peach kept in refrigerator has been studied. According to response surface methodology, were measured 20 treatments repeating 6 times in the center point and effects of the three factors including whey protein (2. 5 to 5 gr), Zataria multiflora Bioss extract (0 to 500 μL) and glycerol (0. 375 to 2. 25 gr) on the physicochemical characteristics, fungal decay and organoleptic traits of peach, were investigated in the condition 5±2 ̊C and 80% relative humidity during 21 days of storage. According to the results, by increasing Zataria multiflora Bioss extract concentration and whey protein of the coating, microbial decay and weight loss of the fruit was reduced and texture and soluble solids were conserved. Peel colour changes of the coated fruit was not significant compare to control and the coated samples had a light and bright colour. Coating peach resulted in natural ripening of the fruit and the coated fruits were softer and juicier than the fruits without any coating. The coating formulations had significant effect on TSS and TA. Optimized points of variables for achieving a coating with the maximum effect on shelf life improvement of peach (Prunus Persica cv. Anjiri) are: whey protein 4. 7475 gr, Zataria multiflora Bioss extract 498. 00 μL and glycerol 0. 6212 gr.
