Food Biotechnology
Asma Entezari; Nasser Sedaghat; Golshan Shakeri
Abstract
Introduction: The main sources of Salmonella for humans are pork, beef, chicken, eggs, fruits, vegetables, and their derivatives such as mayonnaise, and peanut butter. Different species of Salmonella can adapt, grow or survive in different environmental conditions. Salmonella enterica is one of the main ...
Read More
Introduction: The main sources of Salmonella for humans are pork, beef, chicken, eggs, fruits, vegetables, and their derivatives such as mayonnaise, and peanut butter. Different species of Salmonella can adapt, grow or survive in different environmental conditions. Salmonella enterica is one of the main global agents caused by food in humans, and Salmonella typhimurium and Salmonella enteritidis serovars are the most prevalent. One strategy is to use active packaging to reduce the microbial load or prevent the growth of microorganisms on food. Antimicrobial active packaging has received much attention in recent years due to maintaining food quality and safety, and increasing shelf life. Among the antimicrobials used in the food industry, bacteriophages have a very good efficiency to control pathogenic bacteria. Pullulan has a good ability to form a film, its film has good characteristics such as transparency, odorlessness, tastelessness, solubility in water, and low permeability to oxygen and fat, but its problem is related to high price. The combination of polysaccharides with proteins has been done in order to improve the performance and reduce the costs of production films. Gelatin is a suitable option to combine with pullulan in terms of good mechanical properties, reduced permeability, and reasonable price. Different ratios of gelatin and pullulan were studied and suitable film selected, but it needed to modify, so nanofiber cellulose was added in order to improve the mechanical properties and water resistance, adding cellulose nano fiber can be a good and appropriate option. The aim of this research is to evaluate the effectiveness of gelatin-pullulan-cellulose nanofiber antibacterial composite film containing bacteriophage against Salmonella Typhimurium bacteria at two different temperatures over time.Materials and Methods: 6 gr of each gelatin and pullulan were prepared separately and mixed with together at a ratio of 20 gelatin- 80 pullulan. Cellulose nanofiber was extracted from rice bran and were added at three different levels (1 %, 3 %, and 5 %). Commercial bacteriophage solution was added to each of the films separately and the films were prepared by molding method. Zone inhibitory of films containing different percentage of cellulose nanofibers on the agar media against Salmonella typhimurium (104 CFU/ml) were evaluated. As well as, antibacterial effect of selected film on the poultry meat inoculated to S. typhimurium (104 CFU/ml) and numbers of phages on the surface meat at different 4 and 12 temperatures during times were investigated. Results and Discussion: The results indicated that 20 gelatin- 80 pullulan films containing different percentages of cellulose nanofibers showed approximately 2 mm of zone inhibitory compare to the control film, but zone inhibitory among films at different percents of cellulose nanofiber did not observe significant change. The antibacterial effect on poultry meat was dependent on temperature, films loaded with bacteriophages at higher temperature (12 ) was more effective compared to lower temperature (4 ). The populations of S. Typhimurium were decreased 1 log and 0.7 log than control samples at 4 after 7 and 9 days, while at 12 , after 1 and 9 days decreased 1 log and around 2.55 log rather control samples, respectively. In a study, beef inoculated with salmonella bacteria was treated by SALMONELEXTM bacteriophage and resulted in decrease 1.29 log reduction of pathogen bacteria compared to the control sample (Yeh et al., 2017). In another study, the antibacterial effect of double-layer poly lactic acid/xanthan film at 10 °C compared to 4 °C against pathogenic bacteria of Salmonella and Listeria was different and at higher temperatures, the number of pathogenic bacteria decreased more (Radford et al., 2017). The number of phages decreased during times at both temperatures, as well as, their numbers did not significantly change at both temperatures. Kamali et al. (2022) displayed that the release of phages from the film of 30 poly lactic acid/70 whey protein to the meat surface after one hour was 63.22 % and 63.18 % at temperatures of 4 °C and 10 °C, respectively, which presents they did not have a significant difference, after one day at both temperatures.
Ali Shahdadi Sardoo; Nasser Sedaghat; Masoud Taghizadeh; Elnaz Milani
Abstract
Introduction: In Iran, the main problem in greenhouse cucumber production and post-harvest shelf life is short due to the application of traditional packaging and storage methods. This research was carried out in order to investigate on the effects of packaging type and chitosan edible coating on the ...
Read More
Introduction: In Iran, the main problem in greenhouse cucumber production and post-harvest shelf life is short due to the application of traditional packaging and storage methods. This research was carried out in order to investigate on the effects of packaging type and chitosan edible coating on the physicochemical and sensory characteristics of Royal Greenhouse cucumber during storage conditions, in order to prevent of Royal greenhouse cucumber postharvest losses.
Materials and methods: Royal greenhouse cucumbers placed inside the three-layer plastic bags of PE/PA/PE and the effect of different chitosan coating (0, 0.5 & 1 %), concentration of oxygen (3,12 & 21%), storage temperatures (5, 15 & 25 ˚C) and storage time (3, 12 & 21 days) on cucumber quality and shelf life was studied. The quality of cucumber samples was evaluated by weight loss, firmness retention, surface color development (L*, a*, b*), shrinkage and sensory evaluation (taste and freshness).
Results and discussion: The obtained results showed that firmness and organoleptic properties decreased with increasing temperature and time storage, while weight loss and shrinkage was increased, that Leading to loss of cucumber samples quality during storage. Increasing of chitosan coating to 0.5% also showed a beneficial effect on physicochemical and sensory characteristics of the samples during the storage time compared to the control fruit, but by increasing it to 1%, decreased the quality of the final product. The results showed that using modified atmosphere packaging and storage at low temperatures can be in addition to the slow breathing fresh cucumbers from softening and prevent moisture loss the maintenance of cucumber. MAP packaging leads to keeping cucumber green and quality properties compared to the control samples. The optimum condition was obtained at chitosan coating 0.5 %, O2concentration 8.5 %, storage temperatures 9˚C and storage time of 14 days. At this optimum point maximum of firmness, L*, taste, freshness and minimum of shrinkage, weight loss and a* were found to be 10.4 (N), 48.9, 4.35, 4.5, 6.25 %, 2.75 % and -37.28 respectively.
Shohreh Nikkhah; Nasser Sedaghat
Abstract
This research was carried out in order to investigate on the effects of packaging type and storage temperature on qualitative and quantitative characteristics of dried melon. “Thashkandi” and ‘ Khatoni” melon varieties؛ osmotic solutions of 0% and 10% sucrose and cabinet dryer ...
Read More
This research was carried out in order to investigate on the effects of packaging type and storage temperature on qualitative and quantitative characteristics of dried melon. “Thashkandi” and ‘ Khatoni” melon varieties؛ osmotic solutions of 0% and 10% sucrose and cabinet dryer were applied for dried melon production. Dried fruits were packed with modified atmosphere (PE-PA film, 85 micron thickness, two gas mixtures: (70% CO2%, 30% N2(1) and 60% CO2%, 40% N2(2)) and without modified atmosphere (polyethylene and polystyrene films). After 6 months results showed that control dried in 10% osmotic solution preserved in 25°c and 4°c treatment had the most and the least firmness respectively. Melon pretreated by 10% osmotic solution, packed in atmosphere 1 had the least water activity. Dried melon preserved in 4°c had higher L*(brightness) and b*(yellowness) indices. Khatooni cultivar produced dried melon with higher a*(redness). Dried melon pretreated by 10% osmotic solution and packed in atmosphere 2 had less a*(redness). Furthermore dried melon pretreated by 10% osmotic solution and packed in atmosphere 2 and preserved in 4°c had minimum O2% and maximum CO2% in package.
Nasser Sedaghat; Sara Khoshnoudi
Abstract
Introduction : Pistachio (Pistaciavera L.) is a tasty nut and a good source of nutrients. Ithas a high content of numerous beneficial nutritive and bioactive compounds such as proteins, carbohydrate, moisture, vitamins, minerals, fiber and other micronutrients compounds, but the most exceptional components ...
Read More
Introduction : Pistachio (Pistaciavera L.) is a tasty nut and a good source of nutrients. Ithas a high content of numerous beneficial nutritive and bioactive compounds such as proteins, carbohydrate, moisture, vitamins, minerals, fiber and other micronutrients compounds, but the most exceptional components are the amount of fats and especially unsaturated fatty acids. Therefore, this nut is highly susceptible to rancidity, especially after roasting. Despite the high quality, raw pistachio and pistachio processing industry at Iran, export of roasted and packaged pistachio, due to low shelf life and drastic changes intaste, is not very successfull. An effort was made to investigate the efficacy of gelatin in comparison with carboxymethyl cellulose (CMC) as edible coating to retard fat oxidation in roasted pistachio.Materials and methods:Five coating formulations were investigated in this study as follow: A) Gelatin (4% w/v) + ascorbic acid (1% w/v): TGA, B) CMC (1% w/v)+ ascorbic acid (1% w/v): “TCA”, C) ascorbic acid (1% w/v): “TA”, D) Gelatin (4% w/v) + CMC (1% w/v) + ascorbic acid (1% w/v): “TCGA” and 5) control sample (uncoated sample): “TCO”.Roasted pistachio nuts were coated by dipping the nuts in the coating solutions. For each treatment, 100 gram of pistachio nuts were packaged (BOPP/Al/CPP, 80 micron plastic bags) in triplicate. The physicochemical analysis included measurement of free fatty acid (FFA), peroxide value (meq.O2 kg-1),hardness (N), moisture (%) and the sensory evaluation (texture, rancidity, taste and overall acceptability) were performed on coated and uncoated pistachio nuts stored at 35 and 50 °C. The nuts were sampled on the 0th, 1st, 2nd and 3rd month of storage. Data was analyzed using Minitab 16. Analysis of variance (ANOVA) and general linear models (GLM) procedure wereused to compare the mean values of each treatment and Significant differences between the means of parameters were determined based on the results of the Tukey’s multiple range test (p0.05).FFA content of TCGA sample was significantly lower than other samples.The highest protection, according to these criterions, was provided by gelatin-CMC coating containing ascorbic acid.The control samples exhibited more bitterness and off flavor than the coated samples, seemingly on account of chemical reaction and second products of oxidation content. Instrumental and sensory hardness of pistachio nuts which were coated with gelatin and/ or CMC (TCA, TGA and TCGA) were significantly (p
Azam Ayoubi; Nasser Sedaghat; Mahdi Kashani-Nejad; Mohebbat Mohebbi; Mehdi Nasiri mahalati
Abstract
The purpose of this research was study effect of drying conditions (temperature at three levels of 60,70, and 80 oC, air velocity at two levels of 1/5 and 2/5 m/s, and four pretreatments including potassium carbonate and paksan oil, olive oil, hot water and no pretreatment (control)) on drying grape ...
Read More
The purpose of this research was study effect of drying conditions (temperature at three levels of 60,70, and 80 oC, air velocity at two levels of 1/5 and 2/5 m/s, and four pretreatments including potassium carbonate and paksan oil, olive oil, hot water and no pretreatment (control)) on drying grape process and quality of raisin including rehydration, shrinkage, hardness and browning index. The results showed that temperature, air velocity and pretreatment have significant effects on drying rate and quality of raisin. Drying rate increased with increasing temperature and air velocity and with application of preatreatment. The best values of hardness (0.73 N), shrinkage (81/04%) and the least value of browning index (0/157) were related to dried raisin at 60 oC and most value of rehydration (1/266) was related to dried raisin at 70 oC. Air velocity just significantly affected on browning index. Increasing air velocity decreased browning index. Also between used preatreatments , potassium carbonate and paksan oil caused best physicochemical results.
Nasser Sedaghat; Maryam Rastegari; Sara Khoshnoudi; Ali Sharif
Abstract
Introduction: Self-heating packaging (SHP) is an active packaging with the ability to heat food contents without external heat sources or power. Packets typically use an exothermic chemical reaction and then woul be useful for military operations, natural disasters, or whenever conventional cooking is ...
Read More
Introduction: Self-heating packaging (SHP) is an active packaging with the ability to heat food contents without external heat sources or power. Packets typically use an exothermic chemical reaction and then woul be useful for military operations, natural disasters, or whenever conventional cooking is not available. These packages are often used to prepare main courses such as meat dishes, which are more palatable when hot.The system consists of three compartments that are separated within the can: the first is the packaged food item; the second, exothermic chemical material(such as calcium hydroxide); and in the third, water. Once the calcium hydroxide is dissolved within the water, it generates, in just 3 minutes, a large amount of heat (up to 60 degrees Celsius), which heats the food item that is located in the first compartment of the can and allows for it to remain hot for up to 20 minutes.For consumption,consumer must remove a seal on the base of the can to reveal the activation button. Pressing the button activates the heater. After 2-3 minutes, the contents of the can must be lightly shaken to ensure contents are at an even temperature. Setting the can upright, the consumer opens the package and enjoys a hot food or beverage.The present study would focuse on finding the new exothermic chemical materials for reducing cost or producing upper temperature.Therefore, the main objectives of this study were to determine the effect of type and amount of heat-producing compositions on heat-produced and temperature profiles of self heating cans.Material and methods: In this study,the designed self-heating canswere consisted of twoseparated compartments within the can.The first section of can was used for putting of food and the second section was used for storage of exothermic chemical materials. A misture of 6 exothermic chemical materials alkali-acidic, (Sodium hydroxide+citricacid ,Sodiumhydroxide+tartaric acid , potassium hydroxide +citric acid, potassium hydroxide +tartaric acid, Calcium oxide+citricacid and Calcium oxide+tartaric acid) was selected. alkalian-acidic composition was mixed in the ratio 1:1.5 and mixture weighing 150, 200 and 250 g were used in this investigation and placed in the free space between cans. For added degree of heat insulation using of glass wool as label outer of cans. Cans wall andcanned food (canned beans and eggplant caviar) temperature were investigated to determine the best combination of level and type of heat-producing composition. In addition, Time-Temperature profiles of each combination were plotted.Results&Discussion: Observations indicated that amount of Heat-producing compositions had significant effect on heat-generated and the best result was obtained with 250g of Heat-producing compositions(p
Azam Ayoubi; Nasser Sedaghat; Mahdi Kashani-Nejad; Mohebbat Mohebbi; Mehdi Nasiri mahalati
Abstract
Introduction: Raisin is a principal traditional export product of Iran and has a special position in the foreign trade of the country.During storage, the product turns sticky and hard due to exudates syrup and moisture loss. To solve this problem, the application of edible coating would be an appropriatesolution. ...
Read More
Introduction: Raisin is a principal traditional export product of Iran and has a special position in the foreign trade of the country.During storage, the product turns sticky and hard due to exudates syrup and moisture loss. To solve this problem, the application of edible coating would be an appropriatesolution. Edible coating may enhance the boundary layer resistance resulting to the enhanced shelf life of the product. Edible coatings are thin layers of edible materials applied to the product surface in addition to or as a replacement for natural protective waxy coatings and provide a barrier to oxygen, water and solute movement. They are also applied in foods to minimize the migration of components within the food systems or between the foods and their surrounding environment. They are used directly on the food surface by spraying, dipping or brushing to create a modified atmosphere. There are different kinds of films which are used such as polysaccharide, protein, lipid and composites. Lipid based coatings are primarily used for their hydrophobic properties which make them good barriers to water loss. In addition to preventing water loss, lipid coatings have been used to improve appearance by generating a shiny coverin fruits and vegetables, and to decrease respiration, thereby extending shelf life. The moisture barrier properties of hydrophilic coatings can sometimes be improved by addition of lipid materials The purpose of this research was to study the effect of lipid based edible coating (glycerylmonoestearate and carnauba wax) on physicochemical and microbial properties of raisin. Material and methods: Raisin samples (cvAskari)were dried usingsoda oil method and treated with coating materials based on lipid with essential oil of thyme (thymus vulgaris).Glycerylmonoestearate, carnauba wax and tween 80 were purchased from Sciencelab, Sigma-Aldrich and Merck Co. respectively. Raisinswerecoated with the following coating solutions: -Aqueous solution of tween 80 (0.5% w/w) -Aqueous solution of glycerylmonoestearate (0.5% w/w), tween 80 (0.5% w/w) -Aqueous solution of glycerylmonoestearate (0.5% w/w), tween 80 (0.5% w/w), 150 ppm essential oil of thyme -Aqueous solution of carnauba wax (0.5% w/w), tween 80 (0.5% w/w) -Aqueous solution of carnauba wax (0.5% w/w), tween 80 (0.5% w/w), 150 ppm essential oil of thyme Control sample was treated with aqueous solution of tween 80 (0.5% w/w).Distilled water was used for preparing all of coating solutions. Coating solutions were stirred and heated to 75oC (melting point of coating materials) for 30 min on a hotplate with a magnetic stirred to obtain uniform solutions. Dipping technique was used for coating of raisins. The coated raisins were placed on a basket to drip off residual coating solution and were dried in 25oC. The raisin smples were packaged in a 3 laminatedlayer bags (PE/PA/PE) with thickness of 80µ by Henkelman packaging machine and were stored at20, 35 and 50oC for 12 weeks. During the storage period, moisture content, water activity, hardness, color parameters (L*(lightness), a*(redness) and b*(yellowness)), percent of pestilence and microbial properties (total count, mold and yeast) were evaluated. Hardness of raisins was determined in apuncture test using a QTS texture analyzer (CNS Farnelll, Essex, UK) equipped with a needle probe (stainless steel cylinder of 2 mm of diameter with a conical needle bit) and a test speed of 60 mm. min−1 during the test. Hardness was defined as maximum force to puncture raisin from the top to a 2mm depth (Rolleet al. 2011).For colormeasurement, raisins were placed in to a black wooden box (interior size of 0.5 (width) × 0.5 (length) × 0.8 (height) m3 and were illuminated using 3 fluorescent tube lights (10W, 6500K; 40cm in length). A digital camera (Canoon EOS 1000D, Powershot, Taiwan) was located vertically at a distance of 20cm from the raisin surface. The images were preprocessed by Adobe Photoshop software, version 5.5. The Color properties were analyzed using ImageJ software, version 1.44o. The experiments were factorial with a completely randomized design. The coating material, temperature and storage time were the independent variables. Analysis of variance (ANOVA) was conducted for data using MSTAT-C software, version 1.42 (Michigan State University). Differences among the mean values were also determined using Duncan’s Multiple Range test. A significant level was defined as a probability of 0.05. The experiments were carried out on 4, 8 and 12 weeks after storage with three replications. Results and discussion: Results showed that coating, temperature and storage time would have considerable effect on the physicochemical and microbial properties of raisin. Coating caused decreasein moisture loss, hardness, lightness and redness. Increasing temperature and storage time increasedmoisture loss and hardness. Minimum hardness values were measured for 20 oC and 4 weeks storage and maximum hardness values were related to 50 oC and 12 weeks storage. Also it seems that increasing temperature and storage time influences thehardness by increasing moisture loss. Increasing temperature and storage time significantly decreased L* (p≤0.01). Increased enzymatic browning in raisins with increasing temperature was accompanied by an increase in a* value, and a decrease in b* value and caused to presenting dull colors. Total count, mold and yeast of coated samples decreased during storage period. Carnauba wax was more effective than glycerylmonoestearate on stability of raisin. Essential oil of thyme also caused improving color and microbial properties. Least values of redness (-2), total count (2.06 log cfu/g) and mold and yeast (1.32 log cfu/g) were related to carnauba wax coating with essential oil of thyme.
Nasser Sedaghat; Ghodsieh Moradi; Sara Khoshnoudi; Arash Koocheki
Abstract
Introduction:Pistachio (Pistaciavera L.) is a tasty nuts and a good source of nutrients. During the last decade, the worldwide trades of pistachio have increasing trend, likely reflecting on the increase in consumers demand for this nuts. The high oil and essential fatty acid contents of the pistachio ...
Read More
Introduction:Pistachio (Pistaciavera L.) is a tasty nuts and a good source of nutrients. During the last decade, the worldwide trades of pistachio have increasing trend, likely reflecting on the increase in consumers demand for this nuts. The high oil and essential fatty acid contents of the pistachio kernel is important from a nutritional point of view. However, high unsaturated fatty acids content makes pistachio nuts susceptible to oxidation and consequently off-flavors and off-aromas during storage.Mold growth and the production of aflatoxins is another food-safety concern about pistachio nuts. Lipid oxidation and fungal growth can be controlledby using an appropriateatmosphere in packaging.Therefore, the main objectives of this study were to determine the effect of Modified Atmosphere(MA) compared with Vacuum and Air condition packaging on physicochemical, microbialandsensory properties of raw dried Pistachio nuts (ohadi variety) in an accelerated storage conditions at 30±2°C and 50°C for 12 weeks. Material and methods: The pistachio nuts were treated with 3 different system packaging, these treatment includes modified atmosphere packaging (MAP at 88% N2; 10% CO2 and 2% O2), vacuum packaging and air condition packaging. The pistachio nuts were packed in five-layerpouches (2 PE+ 2 PA+1 glue :80 microns)and stored in triplicate at 30°C and 50°C for12 weeksand they were sampled every four weeks. Oil from pistachio kernels for peroxide, and fatty acid assay were extracted by cold extraction and n-hexane was used as extraction solvent. Peroxide value (Meq.kg-1) of the extracted oil was determined by spectroscopic absorbance reading at 500 nm. Free fatty acids (%), as oleic acid percentages in oil samples, were determined using the titration method. Moisture content (%) was determined by drying 5 g of ground kernels at 103±2 °C until constant weight. The mouldcontent (log CFU/g) of pistachios were performed according to the Iran standard method. The textural analysis of the pistachio nuts were performed using cylinderprobe (diameter: 20 mm) at test speed 50 mm/min and deformation of 4 mm for samples. Fracture force (N) and hardness (N) parameters were measured to evaluate textural properties ofpistachio nuts samples.Sensory evaluation was carried out by a 20 member trained panel (10 females and 10 males). Sensory attributes evaluated included color, firmness, rancidity and overall acceptability on 5 point hedonic scale, whit 5 for excellent and 1 for very dislike. Analysis of variance (ANOVA) was carried out using the least significance difference(LSD) test (p
Nasser Sedaghat; Nafiseh Vahedi
Abstract
In this study, quality of white button mushrooms (Agaricus bisporus) treated by water and citric acid was evaluated during storage at 2 temperatures (room temperature and 4°C). The effect of modified atmosphere packaging (MAP, by 4±1% CO2, 6±1% O2 and the remaining N2) with or without ...
Read More
In this study, quality of white button mushrooms (Agaricus bisporus) treated by water and citric acid was evaluated during storage at 2 temperatures (room temperature and 4°C). The effect of modified atmosphere packaging (MAP, by 4±1% CO2, 6±1% O2 and the remaining N2) with or without water absorbent (silicagel) was also evaluated. Samples were assessed for their organoleptic properties (texture, color and spoilage), colorimetery and respiration rate during 12 days of storage. Results showed that among all treatments, water treated samples packaged with MAP method contained silicagel sachet and also stored at refrigerator obtained the most organoleptis scores. This sample retained the optimum level of inter packaging gas composition and finally the best storage time was determined as 8 days.
Parviz Bashiri; Mohammad Hossein Hadad Khodaparast; Nasser Sedaghat; Farideh Tabatabaei Yazdi; Mehdi Nasiri mahalati
Abstract
In this research effectiveness of immersing three types of contaminated pistachios fresh with hull (exocarp or epicarp), dried in shell and dried with hull from Ohady cultivar in ozonated water 0 ppm (control), 4 and 8 ppm ozone concentrations in aqueous solution for range of exposure times 0(control), ...
Read More
In this research effectiveness of immersing three types of contaminated pistachios fresh with hull (exocarp or epicarp), dried in shell and dried with hull from Ohady cultivar in ozonated water 0 ppm (control), 4 and 8 ppm ozone concentrations in aqueous solution for range of exposure times 0(control), 2, 4, 6, 8, 10 and12 hours, to decrease of aflatoxin (B1, B2, G1, G2 and total) were investigated. Water temperature and pH were 10°C and 5.5± 0.3 respectively. For all samples, interaction between, ozone concentration and exposure times or pistachio type, were investigated. Aflatoxin (AF) B1 content was more and was reduced easily. Results showed that differences between the control samples (zero hour and/or 0ppm ozone) and treated pistachios for total aflatoxins and aflatoxin B1 were significant(P < 0.05). For control samples, the means of aflatoxin reduction for B1, B2, G1, G2 and total were, 5.6, 9.7, 14, 6, 15 and 6.4 percentage, respectively and for ozonated pistachios were 32.7, 8.55, 30.6, 34 and 35 percentage, by 4ppm ozone concentration. The results for 8ppm ozone concentration were, 47.9, 12.5, 45.8, 43.9 and 44.4percentage, respectively. The results indicated that the effect of ozonated water on reduction of aflatoxin content from the samples significantly depends on the level of ozone concentration and exposure times. The results also demonstrated that ozone susceptibility of aflatoxins to destruction were B1 & G1 >G2 & B2 respectively.
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 ...
Read More
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
Nasser Sedaghat; Javad Tavakoli
Abstract
This study was done to evaluate quality properties of Pistacia atlantica var mutica (Bene) nuts under deferent storage conditions and packaging. At the zero time, SFA and Total tocopherol (TT) and Total phenolic (TP) compounds were 6.8 and 725.28 and 40.1 mg per kg oil, respectively. Some quality properties ...
Read More
This study was done to evaluate quality properties of Pistacia atlantica var mutica (Bene) nuts under deferent storage conditions and packaging. At the zero time, SFA and Total tocopherol (TT) and Total phenolic (TP) compounds were 6.8 and 725.28 and 40.1 mg per kg oil, respectively. Some quality properties (Peroxide value (PV), Conjugated diene value (CDV) and Carbonyle value (CV)) showed that a limit oxidation was done in the Bene nuts, too. The PV and CDV values of different packaged Bene nut samples during the storage time (12 weeks) didn’t have significant differences (p< 0.05) in the 20, 30 and 50°C but decrease of TT and TP compounds were significant (p< 0.05) under such circumstance. The most amount of degradation of TT compound was 17.9%. Therefore, many of these compounds remained at the end of storage time (12 weeks). The antioxidative effect of these components resulted in low variation in the PV and CDV values at the end of storage time in above mentioned temperatures. The packaging of Bene nut samples by PET/AL/LLDPE multilayer plastic bag was best because of the lowest degree of permeability to oxygen.
Keywords: Bene nuts, Packaging, Fatty acid composition, Total tocopherol, Peroxide value, Conjugated diene value, Total phenolics, Carbonyle value
Younes Zahedi; Nasser Sedaghat; Babak Ghanbarzadeh
Abstract
Novel edible emulsified films were made using pistachio globulin protein (PGP) and palmitic fatty acid at concentrations of 2, 4, and 6 % w/w protein by Tween-80 and homogenization technique. Addition of palmitic acid to the PGP filmogenic solution resulted in great reduction of WVP in the emulsified ...
Read More
Novel edible emulsified films were made using pistachio globulin protein (PGP) and palmitic fatty acid at concentrations of 2, 4, and 6 % w/w protein by Tween-80 and homogenization technique. Addition of palmitic acid to the PGP filmogenic solution resulted in great reduction of WVP in the emulsified films (37-40 %). Concentration of palmitic acid did not create significant difference (P>0.05) among WVP of the emulsified films. The WVP decreased as function of palmitic acid concentration. Water solubility of PGP films was 44.8 % and slightly decreased in the emulsified films. Oxygen permeability of the emulsified films were lower than the PGP films, but the differences were not significant (P>0.05). Tensile strength and elongation at break of the emulsified films were diminished as a result of palmitic acid addition. Incorporation of palmitic acid led to produce the opaque films, which opacity increased as function of palmitic acid concentration. Glass transition temperature (Tg) was determined by differential scanning calorimetry. The Tg of the PGP film revealed at 127.19 °C and was not affected by palmitic acid.
Keywords: Pistachio globulin protein, Palmitic acid, Gas permeability, Elongation, Tensile strength
Mahsa Deylami; Nasser Sedaghat; Fakhri Shahidi
Abstract
Compressed biscuits (CBs) were developed using wheat flour, soy flour, sugar, oil and malt extract. Combining of compression and dehydration technology were applied for production. Packaging CBs using vacuum packaged, use of oxygen absorber (OA) and identical samples were aerobically packaged and stored ...
Read More
Compressed biscuits (CBs) were developed using wheat flour, soy flour, sugar, oil and malt extract. Combining of compression and dehydration technology were applied for production. Packaging CBs using vacuum packaged, use of oxygen absorber (OA) and identical samples were aerobically packaged and stored at ambient and elevated (40°с) temperature for 12 weeks. The effect of different packaging and temperature on chemical (FFA, peroxide value, aw and pH) and sensory (taste, texture and overall acceptability) characteristics of CBs was examined during storage. Free fatty acid (FFA) values showed no significant differences for all packaging treatments. According to peroxide values (PV) oxidation rate in aerobically packed CBs was the highest. These data suggest that OA were effective in prolonging the lag time before the PV started to build up. During storage a decrease in aw and pH values and an increase in FFA and PV values were observed. Although elevated temperature accelerated all chemical reactions but all chemical parameters met national standards. Evaluation of sensory characteristics showed that storage temperature and packaging method had no significant effect on sensory quality of the samples. The good correlation between the PV and taste scores evaluated by panelists suggested that oxidation is one of the main reasons of off flavor in CBs. Overall, the developed compact biscuit was stable at least 12 weeks in all packaging treatments.
Key words: compressed biscuit, oxygen absorber, vacuum packaging, sensory evaluation
Fereshteh Hosseini; Mohammad Bagher Habibi Najafi; Nasser Sedaghat
Abstract
In this study, a flexible package comprises of three layers, polyethylene (100μ), aluminium foil
(9μ) and polyester (12μ) was used for packaging blackcherry preserves. All packed preserves were
kept up to three months at 4 different storage temperatures (4, 23, 35 and 40°C). Physicochemical,
microbial ...
Read More
In this study, a flexible package comprises of three layers, polyethylene (100μ), aluminium foil
(9μ) and polyester (12μ) was used for packaging blackcherry preserves. All packed preserves were
kept up to three months at 4 different storage temperatures (4, 23, 35 and 40°C). Physicochemical,
microbial and organoleptical properties of all trials were determined monthly. As a result, the average
pH, °Bx, acidity, Fe and Pb content were 3.99, 17.49, 0.25, 3.16ppm and 387.98ppb. All
organoleptical properties of samples were acceptable. Temperature had statistically significant effect
on the physicochemical and organoleptical properties of samples. The samples stored at 4 and 23°c
were more acceptable due to their better quality. Flexible pouches have more advantages such as good
colour and constant level of heavy metal as well as low cost and..
Keywords: blackcherry, laminated flexible pouch, packaging, preserve
Nasser Sedaghat; Mohammad Bagher Habibi Najafi
Abstract
The influence of packaging system on stability during storage of raw dried pistachio nuts was studied.
The pistachio nuts were packed in plastic multilayer pouches (PS/EVOH/PE) at different conditions
(atmosphere, vacuum and oxygen scavenger). Accelerated Shelf Life Testing (ASLT) method was
used ...
Read More
The influence of packaging system on stability during storage of raw dried pistachio nuts was studied.
The pistachio nuts were packed in plastic multilayer pouches (PS/EVOH/PE) at different conditions
(atmosphere, vacuum and oxygen scavenger). Accelerated Shelf Life Testing (ASLT) method was
used for evaluation the storage of pistachio at 20, 35 and 50 °C. Samples were analyzed at 4, 8, 12
weeks by using of split-plot design. To follow the oxidation profile, the formation of volatile oxidized
products (Hexanal) was determined by GC-MS. Results showed that the formation of hexanal under
all conditions was significant (p
