Food Technology
Shahab Naghdi; Masoud Rezaei; Mehdi Abdollahi; Mehdi Tabarsa
Abstract
[1]Introduction: Bioactive compounds are substances found in small amounts in food. In addition to their influence on human development, these compounds also play a crucial role in reducing diseases in human. Polysaccharides are a group of bioactive compounds that come from a variety of sources. Polysaccharides ...
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[1]Introduction: Bioactive compounds are substances found in small amounts in food. In addition to their influence on human development, these compounds also play a crucial role in reducing diseases in human. Polysaccharides are a group of bioactive compounds that come from a variety of sources. Polysaccharides are macromolecules that are usually composed of more than ten monosaccharides. The constituent monosaccharides are arranged linearly or branched together through glycoside bonds, depending on the length of the chain and the number of constituent monosaccharides. They also have different molecular weight. Polysaccharides, like other essential macromolecules such as proteins and poly-nucleotides in the body, are essential for the flaxseed body's daily activities and play an influential role in cell-cell communication, cell adhesion, and the identification of molecules in the immune system. A group of polysaccharides derived from marine sources are sulfated polysaccharides. These polysaccharides are a broad branch of the resulting polysaccharides. In industrial quantities, sulfated polysaccharides are produced from pig skin and pig bone, and there are some restrictions on the use of these products in some countries. The limitations on the use of these products made from pig waste are the risks of transmitting influenza, as well as the prohibition of pork in some Islāmic countries. In this regard, by-products from seafood processing, which account for about 20 to 50 percent of the initial weight of raw material, are one of the sources that researchers are considering to extract these compounds. Material and Method: After preparation of the by-product, it was covered with ice in a ratio of 1 to 3 and transferred to the laboratory of Tarbiat Modares University. The sample was then washed and then ground. Finally, it was packed in plastic bags and kept in the freezer at -18 ° C until the day of experiment. Then, the enzymatic hydrolysis method and precipitation by ethanol were used to get sulfated polysaccharides. Chemical analyses were performed to determine carbohydrates, sulfates, proteins, and uronic acid content. The FTIR spectrum of extracted sulfate polysaccharide was determined using an FTIR spectrophotometer in the range of 400-4000 cm-1. Evaluation of antioxidant properties of obtained sulfate polysaccharide was assessed by DPPH free radical scavenging activity, ABTS free radical scavenging activity, and ferrozine tests. Emulsifying and foaming properties were also evaluated as functional properties. Results and Discussion: In the present study, sulfated polysaccharide was extracted from Rainbow trout (Oncorhynchus mykiss) skin by pepsin enzyme and its FTIR spectrum, carbohydrate, sulfate, uronic acid and protein were analyzed. The results of the chemical analysis of the extracted polysaccharide showed that the extraction efficiency was 3.23± 0.02%, as well as the percentage of carbohydrate and protein of the obtained polysaccharide was 57.03± 2 2.56, 7.78± 0.43% respectively. Also, the amount of sulfate and uronic acid were 6.54± 0.77 and 3.86± 0.43, respectively. The results of infrared spectroscopy showed the presence of a broad peak in the range between 3350 and 3450 cm-1 for the –OH group and the S=O sulfate flexural band in the range of 1245 cm-1. An increasing and significant trend was observed in different concentrations used for the DPPH test (p <0.05) which had the highest neutralizing power (38.85%) at a concentration of 2 mg/ml. The highest percentage of ABTS radical chelating was observed at a concentration of 4 mg/mm of distilled water with 71.70% (p <0.05). The chelating results of the extracted polysaccharide against ferrous ions showed that the highest chelating percentage was 98.43% (p <0.05). The foaming capacity, stability properties of the foam, and the emulsifying ability of the studied sample showed a trend of increasing the concentration coefficient of the sample (p <0.05), and the concentration of 10% used sulfated polysaccharide had the highest foaming percentage (72/22%) and foam stability (62.22%) (p <0.05). The emulsifying property of extracted sulfate polysaccharide against soybean oil was higher in all concentrations used than sunflower oil (p <0.05), and the highest value of that was related to the concentration of 10% with 86.57% and 92.59% against sunflower oil and soybean oil (p <0.05). The obtained results demonstrated that the fish skin extracted polysaccharide can serve as a natural antioxidant and functional agent in the food industry
Amir Rezaei; Masoud Rezaei; Mahdi Alboofetileh
Abstract
[1]Introduction: Nowadays, pH indicator has engrossed wide attention because of its eligibility to monitoring shelf life. Intelligent packaging is authoritative of detecting, sensing, tracing, recording and communicating properties to provide information is communicated directly through color changes. ...
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[1]Introduction: Nowadays, pH indicator has engrossed wide attention because of its eligibility to monitoring shelf life. Intelligent packaging is authoritative of detecting, sensing, tracing, recording and communicating properties to provide information is communicated directly through color changes. In the meantime, natural anthocyanins are non-toxic, water- soluble and safe dye that are indicator to pH change. Anthocyanins are a large group of natural dyes. Some natural anthocyanin, such as anthocyanin extracted from mulberry, black bean, blueberry and violet basil (Ocimum basilicum) are used to spoilage monitoring. In present study, an intelligent pH-indicator film based on Arabic gum- Carboxymethyl cellulose incorporated with Violet basil (Ocimum basilicum. L) Anthocyanin was prepared and its properties including structural, physical, mechanical, thermal, antioxidant activity and color sensitivity to changing pH and ammonia gas were evaluated. Materials and methods: For this purpose, at first anthocyanin of Violet basil was extracted and its color reactions were investigated. In next step, the extracted anthocyanin was added to Arabic gum- Carboxymethyl cellulose at different concentrations (40, 60 and 80 mg/100 g film formation solution) and their properties were evaluated. Results and discussion: The results of FTIR and XRD tests showed that the extracted anthocyanin was successfully dissolved in the composite film. Addition of anthocyanin to film matrix led to increasing the WVP and antioxidant activity and decreasing the water contact angle, elongation at break (EB) and thermal properties. The tensile strength value of the prepared films increased from 19 to 23.64 MPa with increasing anthocyanin content from 0 to 60 mg/100 g film solution; but, it decreased with further increase of the anthocyanin content. Exposing the indicator films to ammonia gas and different pHs led to changing the color changes from red to yellow. These color variations of films were consistent with the color changes of the anthocyanin solution. This result indicates that the films prepared sensitive to pH change, and observed different color in films as the solution is changed from acidic to alkaline because causes its structural changes. The structure of anthocyanin is yellow salt ions in acidic solutions, is converted to quinoidal in weak alkaline solutions, and becomes unstructured in high pH solutions.In this study, pH indicator films were prepared based of Carboxymethyl cellulose and Arabic gum containing violet basil anthocyanin. The developed films are non-toxic and biodegradable and provide visible color response. Based on these results can be concluded that the indicator film prepared in present study could be used as intelligent food packaging for visual evolution of freshness/spoilage in food products
Food Technology
Amir Rezaie; Masoud Rezaei; Mahdi Albooftileh
Abstract
Introduction: Films with appropriate mechanical properties and low permeability are very important for food packaging. Natural polymers have gained increasing attention for the development of biodegradable films due to the environmental problems caused by petroleum-based polymers. Carboxymethyl cellulose ...
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Introduction: Films with appropriate mechanical properties and low permeability are very important for food packaging. Natural polymers have gained increasing attention for the development of biodegradable films due to the environmental problems caused by petroleum-based polymers. Carboxymethyl cellulose (CMC) is a linear polysaccharide that exhibited good film forming properties. Gum Arabic (GA) is another polysaccharide that can be used for preparing the edible and biodegradable films. However, several studies have shown that biopolymers like CMC and GA films have high water vapor permeability and poor mechanical properties in moist conditions. One of the strategies that can be used for improving the properties of biopolymers films is blending the different polymers and formation the composite films. Various studies on the preparation of biocomposite films have been performed, however, to the best of our knowledge, studies on combinations of the CMC and AG have not been reported yet. Thus, the main objectives of this study were to prepare CMC/AG composite films using solvent casting method and investigate the effect of different CMC/AG blending ratio on the physical (water vapor permeability (WVP), water contact angle (WCA), color, opacity and light-barrier properties), mechanical and thermal properties. Furthermore, in order to determine the structural characteristics of the films, fourier-transform infrared spectroscopy (FT-IR) and x-ray diffraction (XRD) measurements were also performed. Material & Method: The CMC and AG solutions were prepared by dissolving 1 g in 100 mL of distilled water at 45 °C for 24 h under magnetic stirring. The prepared solutions were then blended in different proportions (75:25, 50:50, and 25:75). After mixing, glycerol (0.3% w/w) was added as a plasticizer and the solution was stirred for 15 min. The prepared solutions were poured into a glass plate, then dried at 45 °C for 24 h in the oven. Finally, the properties of CMC, GA and composite films were determined. Result and Discussion: In this study, biodegradable films composed of CMC and AG were successfully prepared. Results showed that some properties of the composite films were greatly influenced by addition of AG. So that, WVP of films was decreased significantly in the blend films and the lowest WVP was observed in the 25:75 (AG: CMC) films (p < 0.05). The films hydrophobicity was significantly increased from 41.33o to 61.10o by addition of AG to the CMC films (p < 0.05). With increasing the ratio of AG, the tensile strength (TS) of blend films decreased. Opacity and light transmission of the composite films increased and decreased, respectively with increasing the AG ratio. The differential scanning calorimetry (DSC) test demonstrated that the thermal properties of blend films improved with increasing the AG content. The FT-IR analysis indicated that new interaction was generated between the components of the blend films. Generally, it can be concluded that blending the AG and CMC can improve some of the physico-mechanical properties of the blend films
Fatemeh Tabari kouchaksaraei; Masoud Rezaei; Peyman Aryaee; Mehdi Abdollahi
Abstract
Introduction: An edible film is a thin layer, made of edible materials, which once formed can be placed on, or between food components. Protecting the product from mechanical, physical and chemical damages, as well as microbiological activities, are some of its functions (Falguera et al, 2011). The main ...
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Introduction: An edible film is a thin layer, made of edible materials, which once formed can be placed on, or between food components. Protecting the product from mechanical, physical and chemical damages, as well as microbiological activities, are some of its functions (Falguera et al, 2011). The main materials made of these films are proteins, lipids and polysaccharides which are able to be used as alone or in blending form (Hernandez et al, 2008 ;Gennadios, 2004). Carboxymethylcellulose (CMC), is a linear polysaccharide that its natural and biodegradable features cause to exhibit excellent film-forming properties (De Moura et al, 2011). Films prepared with these polymers, generally have good gas barrier properties and moderate to propriate mechanical features (Gutierrez et al, 2012). Using the edible, biodegradable films, due to the sensibility to moisture and poor mechanical properties particularly in moist status, is almost limited (Wang et al, 2009; Silva et al, 2009). Because of high hydrophilic property, CMC films also have a low resistant rate to water vapor permeability (Mohanty et al, 2000). Gum Tragacanth (Astragalus sp.) is another polysaccharide used to produce edible films and coatings. This gum can be widely used as a stabilizer, emulsifier and thickener in food industry, pharmaceutics and cosmetics (Azarikia & Abbasi, 2010). Tragacanth also has a prominent effect on physical and mechanical properties of the potato starch-based edible films (Fazel et al., 2002). It has also a proper blending potential in blending with other hydrocolloids, carbohydrates and most of proteins and lipids (Farahnaki et al., 2009). Yet, not any researches has made about the effect of blending tragacanth gum with other carbohydrate polymers. Blending of polymers can enhance the functional properties of the produced films (Bourtoom, 2008). Hereby, the current study has been done in order to preparate the best edible film with suitable physical, mechanical and biodegradable properties and has tried to introduce an ideal blend film made of different rates of carboxy methyl cellulose and tragacanth. Material and methods: In this research in order to improve the physico-chemical characteristics of biodegradable edible films, blending two polymers of carboxymethyl cellulose (CMC) and tragacanth (Astragalus sp.) was studied. At first, it was tried to making the film. For this purpose in laboratory the solubles of CMC 1% w/w and tragacanth of 0/75% w/w were prepared. In order to dissolute the polymers, both polymers subjected to heat (75 օC) and following the temperature decrease (~ 40 օC), glycerol (20% of the polymer) was added to each one. Therefore, CMC and tragacanth were blended to each other at proportions of 25:75, 50:50, and 75:25 (v/v) and water vapor permeability, solubility, mechanical properties and microstructure were evaluated. Microstructure of the produced films was assigned by an electronic microscope (Philips, made in Netherlands). Thickness of samples was determined by a digital balance (0/0001 mm, Mitutoyo- made in Japan) via measuring in five points of each sample. Water vapor permeability, moisture content and solubility rate were conducted by standard. Tensile strength (TS) and elongation at break (EAB) were determined using an Instron universal testing machine (Model TVT 300 Xp, Sweden) operated according to the ASTM standard method D882-01(ASTM, 2002). Statistical Analysis performed by software of SPSS, ver. 20. Normality of data and homogeneity of data were conducted by Kolmogorov-Smirnov and Levene tests, respectively. For significance of treatments effect One-Way Anova and for statistical comparison of data Duncan test were performed. Results and discussion: The results showed that blended film of 50:50, as well as pure CMC film, had a smooth, flat surface without crack, showing that both polymers were properly blended. Among three blend proportions of two polymers, tensile strength was greatest in 50:50 whereas this amount in proportions of 50:50, 75:25 and 25:75 was recorded 44.59, 32.82 and 26.59 MPa, respectively. These results were in line with Ghanbarzadeh et al. (2011), who indicated the quality of maize starch-based films was suited by CMC and citric acid. With decrease of CMC content in blended films the elongation rate of films significantly decreased. This can be attributed to suitable interactions of the two polymers. This is in accordance with report of Tongdeesoontorn et al. (2011) and Mu et al. (2012), who found the different contents of CMC positively affected the films properties. Water vapor permeability was of better status at 50:50 and 25:75 than at 75:25. Solubility in water did not differ among three blend films but it had better conditions in pure CMC film whereas the blend films showed a decrease about 52 to 58% in solubility compared to the pure CMC film. The results of our research is consistent with findings of Tong et al. (2008), who investigated preparation and properties of pullulan -alginate- CMC blend films. The decrease of solubility can probably be due to proper interactions between CMC and tragacanth. Likewise, blending two polymers at different proportions decreased the moisture content of films. It can be stated that because of the linkages between tragacanth and carboxymethyl cellulose polymer chains, a compact structure has been created that not allows water molecules to presence and thus leads to a reduction in moisture content of films. This is in accordance with findings of Gutierrez et al. (2012), who reported that the increase of leaf extract in plant of murta improved the quality properties of the CMC films. Generally, from this investigation it is deduced that blending the two polymers in different proportions can improve some physico-chemical properties of the CMC- tragacanth edible film.
Sana Rabiei; Hedayat Hosseini; Masoud Rezaei
Abstract
The inhibition of pathogens growth as well as the shelf-life extension of seafood as a perishable product using safe methods is one of the most important issues that have been attracted fisheries and food science researcher’s attention. The purpose of this study was to evaluate the inhibitory effect ...
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The inhibition of pathogens growth as well as the shelf-life extension of seafood as a perishable product using safe methods is one of the most important issues that have been attracted fisheries and food science researcher’s attention. The purpose of this study was to evaluate the inhibitory effect of Bunium persicum essential oil (EO) on inoculated Listeria monocytogenes growth in simulated broth culture models and fillet of Kutum (Rutilus frisii kutum). Black zira EO at 0.05%, 0.2% and 0.4% levels were added in fish peptone broth and Kutum broth, after each of them immediately had been inoculated with 104 CFU/ml L. monocytogenes and antilisterial properties of them were assessed in comparison with control group at refrigerator temperature (4 °C) for 12 days .Then the effect of Black zira EO at 0.2% and 0.4% levels on inoculated L. monocytogenes growth in kutum fillet was determined. Black zira EOs showed the strong bactericidal activity in fish peptone broth. However, this effect significantly decreased in kutum broth .The inhibitory effects of Black zira EO in kutum fillet was impressively lower than in fish simulated broth culture models.
Elham Garmsiri; Masoud Rezaei; Amirreza Shaviklo; Aria Babakhani
Abstract
Seaweeds are the novel bioactive compounds resources with antioxidant activity. The aim of this study was to evaluate the efficacy of microwave radiation on antioxidant compounds extracted from red algae Hypneahamulosa and optimal extraction conditions using response surface methodology (RSM).. Independent ...
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Seaweeds are the novel bioactive compounds resources with antioxidant activity. The aim of this study was to evaluate the efficacy of microwave radiation on antioxidant compounds extracted from red algae Hypneahamulosa and optimal extraction conditions using response surface methodology (RSM).. Independent variables were time (4,8,12 min), acetone/water concentration (50%,75% ,100% acetone) and power microwave (200,300.400 W). Antioxidant activity of red algae was measured using DPPH radical scavenging activity assay.DPPH value varied from 4.19 to 72.99%. The optimal extraction conditions was include acetone concentration of 50%, at 12 min and microwave power of 200 W.The actual experimental values were in close agreement with the predicted values from the developed quadratic polynomial equation .R-squared was obtained99% that shows suitability of the model useded and the success of RSM in optimizing the extraction conditions.
Masoud Rezaei; Ali Motamedzadegan
Abstract
To investigate the optimum conditions for extracting gelatin from whitecheek shark (Carcharhinus dussumieri (skin, response surface methodology (RSM) has been adopted. In this research, the effect of NaOH concentration (0.01-1 N), HCl concentration (0.01-1 N), and extraction time (3-8 h) on dependent ...
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To investigate the optimum conditions for extracting gelatin from whitecheek shark (Carcharhinus dussumieri (skin, response surface methodology (RSM) has been adopted. In this research, the effect of NaOH concentration (0.01-1 N), HCl concentration (0.01-1 N), and extraction time (3-8 h) on dependent variables, yield and melting point of the skin gelatin have been studied using central composite design. Based on the individual regression models, predict values of multiple response at optimal condition were %23.222 (yield), and 32.224 °C (melting point). The best pretreatment conditions to get to the optimum properties were 0.01 N NaOH, 0.135 N HCl and 3 h extraction time. The results showed that, NaOH and HCl concentrations had significant effects, but extraction time had no significant effect on gelatin extraction yield and its melting point.
Behrouz Mohammadzadeh; Masoud Rezaei
Abstract
In this research green tea extract was prepared with water and then fishes in whole and gutted fish form was dipped in solutions of green tea extract (600 ppm) for 90 minutes and then were icing. During storage period (16 days), spoilage oxidation (PV, FFA, and TBA), spoilage microbial indices (TVB-N, ...
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In this research green tea extract was prepared with water and then fishes in whole and gutted fish form was dipped in solutions of green tea extract (600 ppm) for 90 minutes and then were icing. During storage period (16 days), spoilage oxidation (PV, FFA, and TBA), spoilage microbial indices (TVB-N, TVC, PVC) and Sensory assessment with interval of 4 days were measured and compared with control treatment. Based on obtained results in all of treatments by passing time the value of all of the indexes (PV, FFA, TBA, TVB-N, TVC and PVC) increased significantly (P < 0/05). But this increase in treatments dipped in 600 ppm solution was performance slowly. Also in gutted fish form was caused higher delay in lipid oxidation and spoilage microbial relate to whole fish form. According sensory assessment results not significantly different among treatments (P > 0/05). In conclusion Obtained results showed that green tea extract with dipping gutted fish in consternation of 600 ppm was suggested for retardation of lipid oxidation and microbial spoilage in rainbow trout during storage in ice.
Mehdi Abdollahi; Masoud Rezaei; Gholam Ali Farzi
Abstract
A bionanocomposite film was developed by nanoclay incorporation to chitosan films, using a solution casting method and the effects of nanoclay concentration (0.5, 1.0, and 3% w/w) on the physical and mechanical properties of the chitosan films were evaluated. Moreover, X-ray diffraction (XRD), scanning ...
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A bionanocomposite film was developed by nanoclay incorporation to chitosan films, using a solution casting method and the effects of nanoclay concentration (0.5, 1.0, and 3% w/w) on the physical and mechanical properties of the chitosan films were evaluated. Moreover, X-ray diffraction (XRD), scanning electron microscopy, and fourier transform infrared spectra (FTIR) were used for studying microstructure and internal interaction of the chitosan-based films. It was found that the water vapor permeability and the water gain of the chitosan films decreased more than 45% with nanoclay incorporation up to 3%. Moreover nanoclay improved the tensile strength of the chitosan films about 20%. XRD and FTIR results confirmed that the improvements in the nanocomposite properties may be due to the exfoliation of the nanoparticles, good interaction between nanoclay and the functional groups of chitosan chains, and good cross links in polymeric matrix.
Keywords: Nonocomposite, Chitosan, Nanoclay, Mechanical properties
