جستجوی مقالات مرتبط با کلیدواژه « کیتوزان » در نشریات گروه « صنایع غذایی »

Eggs are one of the low-cost sources of protein and are also perishable, so maintaining their internal quality during storage is particularly important. The current research was carried out with the aim of the effect of nanocomposite coating on the physicochemical changes of eggs during storage for 4 weeks. Uncoated eggs (control) and eggs treated with a two-component coating of polyvinyl alcohol/chitosan (PC), a three-component film of polyvinyl alcohol/chitosan/montmorillonite (PCM) ), and PCM films incorporating concentrations of 2 and 4% garlic extract were evaluated in a total of 5 treatments and 3 replicates in a completely randomized design. The results showed that the concentration-dependent antimicrobial effect of garlic extract was higher against Staphylococcus aureus than Escherichia coli. The prepared films of active three-component PCM nanocomposite had greater thickness, higher tensile strength, and elasticity, lower solubility, less elongation at break, and lower water vapor permeability (p<0.05). At the end of 4 weeks of storage, the eggs coated with active three-component PCM nanocomposites had a thicker shell (0.400 mm) and a stronger shell (0.310 kg), causing less weight loss (About 4 %), Haugh unit (70.00) and yolk index (0.43) were higher and the lowest of total viable count bacteria (4.1 log cfu/ml). Therefore, using the three-component PCM nano-coating containing 4% garlic extract as a biodegradable packaging is possible to maintain the internal quality and eggshell and increase its storage time at ambient temperature.

The purpose of this study was to investigate the effect of chitosan coating and Ferulago angulate essential oil on button mushroom (Agaricus Bisporous) shelf life. Therefore, Ferulago angulate essential oil was extracted by clevenger method and whit different concentrations of chitosan (control sample without chitosan and essential oil, with 0.5% chitosan, chitosan with two different concentrations of 100 and 150 ppm) were used to coating the mushroom samples. After packing, the samples were stored in the refrigerator at 4°C for 15 days and samples were evaluated for physicochemical, structural and sensory tests every 3 days. With increasing shelf life, the hardness of all coated samples decreased and addition of chitosan to samples could have a positive effect on increase the hardness of the samples during storage, which was significantly increased by adding Ferulago angulate essential oil. All color parameters were significantly retained (P<0.05) By adding chitosan which the addition of essential oils exacerbated these conditions. Using the chitosan significantly (p<0.05) reduced the weight loss of samples, but the addition of essential oil had no significant effect on reducing weight loss changes. The use of chitosan significantly (p <0.05) prevented the growth of total count of microorganism and molds and yeasts, and the addition of essential oil to chitosan as a preservative compound also exacerbated the inhibition of microorganism growth. Similar results were also true for color and appearance evaluation. Chitosan structure, antimicrobial properties and phenolic compounds in essential oils were the main reason for maintaining the quality of mushroom samples during storage.

The purpose of this research is to encapsulate the phenolic compounds of rhubarb stem's juice with chitosan and soy protein isolate and checking their effects on the properties of pomegranate juice. For this purpose, the phenolic compounds of rhubarb stem's juice were extracted by methanol and encapsulated with chitosan and soy protein isolate by nanoemulsion method, and finally the resulting microcapsules and nanocapsules were used to enrich pomegranate juice samples. The highest percentage of encapsulation efficiency of phenolic compounds was with soy protein isolate (45.26%). The results of SEM images showed that the particles were relatively spherical and with a relatively smooth surface, also chitosan nanocapsules with an average size of 281.4 nm and soy protein isolate microcapsules with an average size of 22.33 µm were formed. The results of pH analysis showed that the samples enriched with chitosan nanocapsules and soy protein isolate microcapsules showed more and less pH decrease than the control samples during the storage period. The results of DPPH radical scavenging activity showed that the enrichment of pomegranate juice with chitosan nanocapsules increased the antioxidant activity of the samples for up to 3 months of storage.

Cherry, with the scientific name Prunus avium L., is one of the most important stone fruit trees in temperate regions, belonging to the Rosaceae family and the Prunoideae subfamily. Edible coatings are thin layers of materials that are used on the surface of the product and are an alternative to protective wax coatings. Chitosan is a coating that has a polysaccharide structure and is composed of glucosamine and N-acetylglucosamine units and is obtained from the shell of crustaceans such as crabs and shrimps. Clear, odorless, non-sticky gel with high and firm absorption power is extracted from the inner parts of aloe vera plant leaves. Between this gel and the outer skin of the leaf, there are special cells that contain a yellow liquid and when this liquid dries, aloe vera juice is produced. This gel is completely healthy and compatible with the environment, and its pH is about 4.5, which can replace various fruit coatings in the post-harvest stage. The purpose of this research was to investigate the combined effect of aloe vera gel and chitosan in maintaining the quality characteristics post harvesting and increasing the shelf life of Lombard cherry fruit.

Lambert black cherry fruit was obtained from the garden complex of Moghan Agriculture and Animal Husbandry Company located in Pars Abad city of Ardabil province. they were immediately transferred to the Postharvest Physiology Laboratory, Department of Horticultural Sciences, Faculty of Agriculture and Natural Resources, Mohaghegh Ardabili University, for the desired treatments.This study aimed to extend the shelf life of cherry fruit with two edible chitosan coatings (0, 0.5, 1, 1.5% w/w) and aloe vera gel (0, 15%, 30%, 45% w/w) was performed as factorial in a completely randomized design in three replications. The measured parameters were soluble solids, vitamin C, total acidity, anthocyanin, starch, weight loss and firmness of fruit tissue that were evaluated at harvest time and 45 days after harvest.

The results of analysis variance showed that the effect of time had significant on cherry fruit flavor (P<0.01). The use of Aloe vera gel had a significant effect (P<0.01) on soluble solids, starch, firmness, fruit flavor and also weight loss (P<0.05). The effect of chitosan treatment also were significant on total soluble solids, starch, firmness, and fruit flavor (P<0.01). Moreover, Interaction effect of aloe vera gel and chitosan treatments on total soluble solids, starch, firmness, and fruit flavor were significant (P<0.01) during at storage time. The compare means showed that the ratio of soluble sugars to total acid was increased. The highest soluble solids and their ratio to total acid were obtained as a result of the using of 45% aloe vera gel with 0.5% chitosan coating. Combining of aloe vera gel with 30% and 45% concentrations with chitosan at 1% and 1.5% were able to maintain better firmness of fruit tissue compared to other treatments during storage time.The highest residual starch in the fruit was obtained in using aloe vera gel treatments at concentrations of 15%, 40% and 45% with 1% chitosan during storage. Also, the use of aloe vera gel (all three levels) was exceled compared to control on fruit weight loss. By reducing the activity of ethylene, chitosan causes a delay in ripening and aging and as a result reduces the firmness of the fruit. Aloe vera gel reduces the activity of pectin methylesterase, poly-galactronase and beta-galactosidase. These enzymes destroy the cell wall and soften the fruit.

The interest in using edible coatings to maintain the optimum quality of fruits during the marketing and storage process has increased. Edible coatings can act as a barrier, thereby reducing quality loss, inhibiting gas exchange, controlling respiration rates, and preventing the growth of microorganisms that cause fruit decay. The results clearly indicated the preservation of the quality of cherry fruit with the use of edible coatings compared to the control. The use of the treatment combination of chitosan at a concentration of 1.5% with aloe vera at a concentration of 45% has had a positive and significant effect to maintain the quality of cherry fruit after harvesting. Therefore, the use of this treatment combination is recommended to increase the storage life and maintain the quality of Lambert cherry fruit during the storage period.

Cucumber is an economically important crop, containing vitamins, minerals, antioxidants, and flavonoids. However, due to loss of weight and firmness, microbial contamination, mechanical damage, and yellowing, the storage duration of cucumber is limited to 3–5 days at room temperature. Therefore, pretreatments are crucial for prolonging its shelf life. Chitosan is a cationic polysaccharide and can interact electrostatically with anionic, partially demethylated pectin. Besides, chitosan has inhibitory effects on fungal rot and prevents weight loss in fruits. Pectin can form excellent films. Because of increasing demand to reduce synthetic chemicals as antimicrobial agents, substances derived from plants, such as essential oils, can play a significant role in the future.  Several essential oils and essential oil components have shown antimicrobial activity against spoilage and pathogenic microorganisms during fruit and vegetable storage. Essential oils of thyme and cinnamon contained phenolic groups have been found to be most consistently effective against microorganisms, however, essential oils are volatile and irritant. Therefore, forming an inclusion complex using b-cyclodextrin can improve solubility, control volatile, and induce off-flavors and unpleasant odor of the essential oils. The objectives of this study were to develop the microencapsulated thymol (thyme) and trans-cinnamaldehyde (cinnamon) essential oils to produce antimicrobial agents and subsequently evaluate the effectiveness of edible coating made of chitosan and pectin containing microencapsulated trans-cinnamaldehyde or thymol essential oils to improve qualitative and quantitative characteristics and shelf life of cucumber.

The inclusion complexes of trans-cinnamaldehyde and thymol in beta-cyclodextrin (CD) were prepared separately by freeze-drying. Each essential oil was dispersed in 1000 ml of beta-cyclodextrin aqueous solution (16 mmol/L, 18.15 g) in molecular ratio 1:1 (2.4 gr thymol, 2.11 gr trans-cinnamaldehyde) and mixed in a laboratory stirrer for 24 hour at room temperature , then frozen (-70 ºc) and freeze-dried (<20Pa, 48 h). Lyophilized samples were stored inside a freezer (-20 ºc) until further use. Cucumbers cv. Nagene with uniform size, appearance, ripeness and without mechanical damage or fungal contamination were selected. Then They were then sanitized by immersion in chlorine solution (150 mg/kg) for 1 min and air dried. Edible coatings were prepared as three immersion solutions of chitosan, pectin, and calcium chloride (CaCl2). The fruits were coated with pectin (1%) and chitosan (0-0.5%-1%) containing beta-cyclodextrin microencapsulated trans-Cinnamaldehyde or thymol each (0-0.25%-0.5%). After coating by chitosan, the fruits were immersed in 1% Calcium chloride solution to induce crosslinking reaction. After dipping step, fruits dried for 8 minutes at room temperature to remove the excess solution attached to the surface .Uncoated fruits served as control. Then fruits were preserved in cold storage (temperature: 10ºc; relative humidity: 90-95%) for 15 days. chemical (total soluble solids, titratable acidity) and physical (total color difference, Hardness, and weight loss) Characterization of fruits were measured immediately after harvest and after 5, 10 and15 days. Microbial tests (total count, mold, and yeast) were done at the end of preservation time. Analytical data were subjected to analysis of variance and factorial adopted completely randomized design and a Duncan comparison test was used. 

The results showed that weight loss, total soluble solids, and the total color difference increased and hardness and titratable acidity decreased gradually in all samples during cold storage (<0.05). Chitosan and essential oils slowed down this rising or decreasing trends. Interactive effects of chitosan, essential oil type, essential oil concentration, and storage time had positive effects on these quality attributes. The fruits coated with the highest concentration of chitosan (1%) and thymol (0.5%) essential oils showed the least weight loss, loss of hardness, and color change throughout 15 days of storage. Besides thymol in comparison with trans-Cinnamaldehyde was more efficient to prevent yeasts and molds on the surface of cucumber. By increasing chitosan and essential oil amounts, the ability of inhibiting microbial growth by coating is enhanced. 

The results of chemical, physical and microbial tests, showed that multi-layer coating solution containing chitosan 1% with thymol 0.5% was effective in extending the shelf life of cucumber. The combined usage of microencapsulated thymol essential oil and chitosan-based coating on cucumber could be considered a healthy and effective treatment that reduces microbial spoilage and preserves quality and color characteristics in cucumber and represents an innovative method for commercial application. Therefore, this coating can be used as an alternative to chemical fungicides to prevent fungal rot of cucumber and other fruits, however, it is suggested that more studies should be done in this field.

Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ways to overcome this issue. In this research, caffeine was encapsulated in nanoliposomes coated with chitosan and then the drink powder enriched with caffeine nanochitosome was produced.
 
 In this research, pure caffeine powder was purchased and stored in dry environment at room temperature. Ethanol (96%) and acetic acid were obtained from Mojallali Company, Tween 80 from Merck Company (Germany), lecithin (P3556), cholesterol (C8667), and chitosan (medium molecular weight) purchased from Sigma Aldrich Company (Germany). Sugar, essential oil and citric acid used in the formulation of the drink were purchased from a local store.
 First, nanochitosomes in ratios of 9:1, 8:2 and 7:3 lecithin-cholesterol, were prepared using thin-layer hydration method. Then, the particle size and zeta potential were measured to determine the characteristics of the produced particles. Encapsulation efficiency was measured for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios. The stability of the chitosomal sample with a ratio of 9:1 lecithin-cholesterol was evaluated through visual observation of precipitation formation and the amount of release of encapsulated caffeine during 60 days of storage at ambient temperature was calculated. FTIR was performed for each of the components of the wall of chitosomes, caffeine powder, chitosomal solution containing caffeine and chitosomal solution without caffeine with a ratio of 9:1 lecithin-cholesterol. Nanochitosomes with 9:1 lecithin-cholesterol ratio were used in the formulation of beverages due to having the smallest particle size, favorable zeta potential, the highest microencapsulation efficiency, and high stability during storage. The drink samples were prepared in different formulations (samples containing 3 and 5% free caffeine solution, samples containing 3 and 5% chitosomal caffeine solution and the control sample). Then, the drinks were evaluated in terms of sensory characteristics and other physico-chemical characteristics (pH, acidity, Brix degree, etc.). The drinks produced were turned into powder with a freeze-dryer machine, and two important characteristics of powdered products, i.e. water solubility index and their hygroscopicity, were evaluated.
 
 The average particle size and zeta potential for different ratios of lecithin -cholesterol were obtained in the range of 133.3-443.6 nm and +40.96 to +48.36, respectively. The encapsulation efficiency for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios were 91.2%, 86.18% and 79.09 %, respectively. The chitosomal sample with 9:1 lecithin-cholesterol ratio showed good stability during 60 days of storage at ambient temperature. FTIR results showed that caffeine was loaded in nanochitosomes. The results of the sensory evaluation of the prepared beverages showed the acceptability of the taste of the samples containing caffeine nanochitosome compared to the samples containing free caffeine, which indicates the success of chitosomal nanocarriers in covering the bitter taste of caffeine. The results of measuring the color of different drink samples showed that there is no significant difference between the color of samples. The results of measuring pH and acidity did not show significant differences between different drink samples. The results of measuring the solubility of different drink powder samples showed that the samples containing caffeine nanochitosomes have low solubility compared to other drink powder samples. Also, the hygroscopic amount of the drink powder containing caffeine nanochitosomes was lower than the other samples, which is considered as an advantage for powdered products.
The results obtained in this research showed that nanochitosomes are an efficient system in covering the bitter taste of caffeine. Therefore, with the production of caffeine nanochitosomes and its usage in the formulation of powder drinks, it is possible to produce energizing and desirable drinks without the need to use high amounts of sucrose.

The cream is a product obtained from the physical separation of milk and its conversion from fat emulsion to fat-free milk. Milk, its products like cream, are susceptible to microbial spoilage. Often, the color, smell, and taste of dairy products become undesirable due to the decomposition of existing proteins and fats with enzymes produced by microorganisms. The main cause of spoiled milk and its products that are kept at low temperatures is psychrophilic bacteria. Pseudomonas, Bacillus, and Streptococcus can be mentioned as psychrophilic bacteria. They grow well at a temperature lower than 15°C and can grow at a temperature of 4°C. Due to their proteolytic and lipolytic properties, these bacteria easily spoil milk even if it is kept at relatively low temperatures. Natural extracts with antimicrobial properties can be used to reduce the microbial load of dairy products, including cream. Polyphenols are the most important and numerous secondary groups of metabolites in the plant kingdom. These compounds play a role in defense against ultraviolet rays, oxidizing agents or invasion, and some plant pathogen agents. Quinoa belongs to Chenopodiaceae family, Chenopodium genus. Its plant name is Willd quinoa Chenopodium. Quinoa is a native cereal of South America. Quinoa and its products are rich in macronutrients, such as protein, polysaccharides, and fats, and also rich in micronutrients, such as polyphenols, vitamins, and minerals. Ginseng belongs to the Araliaceae family, and it is found throughout East Asia and Russia. The properties of this plant include its anti-inflammatory, antioxidant, anti-obesity, anti-allergy, anti-blood pressure, memory improvement, sexual enhancement, anti-diabetes properties, and anti-tumor properties. Ginseng also adjusts metabolism, immune functions, and blood pressure. Ginseng plant and red quinoa seeds contain high phenolic and flavonoid compounds and also have antimicrobial properties. On the other hand, extraction affects the compounds in the extracts. Extraction with the help of ultrasound is one of the green extraction methods. The encapsulation method is used to protect bioactive compounds (polyphenols, enzymes, antioxidants, micronutrients), and its purpose is to protect bioactive compounds from harmful environmental effects, and to control release. On the other hand, so far no research has been done in the field of investigating the antimicrobial effect of quinoa and ginseng extract coated with different walls (chitosan, whey protein, chitosan/whey protein) on the shelf life of cream .In this research, extracts from ginseng and red quinoa seeds were obtained by ultrasound prop. Then the extracts were nano-microcoated. The antimicrobial effect of the nano-encapsulated extracts on the cream was investigated. In this extraction process, an ultrasound probe was used. The ratio of solvent to sample was 10:1. First, the dried powder was added to the desired solvent, and the ethanol-water solvent with the ratios (50:50) and (80:20) was separately subjected to ultrasonic waves with a frequency of 37 Hz and an intensity of 100 and a temperature of 40°C for 15 minutes was placed. Then, the chemical compounds of the obtained extracts were measured using GC-MS. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of ginseng and quinoa extracts were determined with an ethanol-water solvent with two different ratios (80-20 and 50-50). Then nano-emulsions containing ginseng, quinoa, and ginseng + quinoa mixture with different walls (chitosan, whey protein, chitosan/whey protein) were prepared. Encapsulation efficiency, particle size, and pH of nanoemulsions were investigated. Also, the antimicrobial properties of the cream containing nano-encapsulated extracts on different bacteria (Staphylococcus aureus, Bacillus subtilis, Salmonella, E. coli) at two temperatures of 4 and 25 degrees Celsius during the storage period of 14 days (the first day, 7th day, 14th day) was measured. The highest phenolic composition in ginseng and quinoa extracts was related to m-coumaric acid (111.09) and ellagic acid (73.88) microgram/gram, respectively. The highest amount of flavonoid compounds in ginseng and quinoa extracts belonged to catechin and rutin, respectively (29.6) and (34.12) micrograms/gram. The amount of MBC of Staphylococcus and Bacillus was higher in the ginseng extract. However, the MBC and MIC of E. coli and Salmonella bacteria were higher in quinoa extract. The pH of nanoemulsions varied between of 5.86-6.11 and the chitosan wall had the smallest size and the highest encapsulation efficiency. In the present study, nanoemulsions with chitosan walls and cheese juice had the highest (72.79 containing quinoa extract) and the lowest (59.9 containing ginseng and quinoa extract in a ratio of 1:1) encapsulation efficiency, respectively. Quinoa extract nano-encapsulated with chitosan wall had effects on reducing the number of tested bacteria (Staphylococcus aureus, Bacillus subtilis, Salmonella, E. coli) than other extracts. In the cream containing nano-encapsulated quinoa extract, on the 14th day, Staphylococcus was 2.19 and 1.63 logarithms at 4 and 25 °C, respectively. The number of Bacillus cereus at 4 and 25 °C was logarithm 1.03 and 1.9, respectively. However, Salmonella at 4 and 25 °C were 2.73 and 2.36 logarithms, respectively, and E. coli were 2.88 and 2.47 logarithms, respectively. After the quinoa extract, the mixture of ginseng and quinoa extracts had the most effective in reducing the number of bacteria, and finally, the nano-encapsulated ginseng extract showed the least effect in reducing these four bacteria present in the treated creams. Also, the rate of reduction of Staphylococcus and Bacillus was higher at 4°C compared to 25°C. Because Staphylococcus and Bacillus are mesophilic and thermophilic, respectively, which grow more easily at high temperatures and are sensitive to low temperatures. But Salmonella and E. coli were more sensitive to 25 °C than 4 °C. According to the results, different extracts had the most reducing effect on Bacillus cereus at 4°C and the least reducing effect on E. coli at 4°C. Given that the results showed that quinoa and ginseng extracts have various phenolic and flavonoid compounds. Also, the MBC and MIC of the extracts showed high antibacterial properties. The use of chitosan as the wall of nano-encapsulated extracts was better than other walls in terms of encapsulation efficiency and particle size. Also, nano-coated quinoa extract with chitosan wall added to cream during storage at 4 and 25 degrees Celsius had a greater effect in reducing the tested bacteria (Staphylococcus aureus, Bacillus subtilis, Salmonella, E. coli) than other extracts, which indicated the higher antimicrobial properties of quinoa extract and also the better retention of these extract compounds by the chitosan wall. As a result, quinoa extract coated with chitosan wall can be used in fat-based dairy products, including cream, due to its natural antimicrobial properties. Because it reduces the microbial load of dairy products and thus increases the shelf life of dairy products.

 Potato strips are one of the most widely consumed products, and due to their high oil content, they have caused public health concerns. Therefore, efforts to reduce oil absorption can alleviate these concerns to some extent. Edible coating is an effective way to reduce oil uptake, because the oil absorption is a surface phenomenon. Edible coatings should adhere well to the surface of the product and provide a uniform and complete coverage for the product. Preventing the migration of oxygen, carbon dioxide, aromas, oils, moisture, improving the appearance of food and mechanical properties. In this study, the possibility of reducing oil absorption in French fries was investigated using okra mucilage and chitosan as edible coatings.

 The okra was washed and then cut into about 1 cm pieces and poured into containers with lids. Then water in a ratio of 2:1 weight of okra was added to the container and completely covered its surface. The okra were refrigerated for 72 hours until the mucilage was completely extracted. Then the mucilage was smoothed. This solution was considered as 100% mucilage solution. To prepare a 50% solution of okra mucilage, 100% solution was mixed with an equal amount of distilled water and filtered. To produce a solution of 0.75 and 1.5% of chitosan, 7.5 and 15 g of chitosan powder was dissolved in 1000 ml of 1% acetic acid and then adjusted to pH 5. Then 5 g of glycerol was added as a plasticizer. The potato slices were first blanched in 0.5% calcium chloride solution at 90°C for 5 minutes. Then, they were immersed in coating solutions at 60°C for 5 minutes. After coating, the potato strips were fried at 180°C using a fryer and then various characteristics including coating percentage, oil absorption, and moisture content, texture firmness, peroxide value, acid number, color indices and sensory properties were examined. Design Expert 8.0.7.1 software was used to analyze the results and to draw the curves.

Results and Discission:

 The results showed that the increasing the amount of chitosan led to better coating formation in comparison with okra. The highest coverage was observed in the concentration of 1.2% chitosan and 0% okra mucilage (2.38%) and the lowest was observed in the control sample (0.11%). It was also observed that with increasing the concentration of chitosan and okra mucilage, the amount of oil absorption decreases. However, the amount of oil absorption in high concentrations of okra mucilage increased slightly. The highest oil uptake in the control sample was 20% and the lowest was observed in the sample of fried strips covered with 41% okra mucilage and 1.5% chitosan at 15.44%. The obtained model of oxidation index was not significant. The effect of okra mucilage and chitosan concentration on the texture of the samples (p <0.05) and the color indices of a* (p<0.01) and L* (p <0.05) were significant. For sensory attributes, the highest and the lowest taste score was observed for samples coated with 100% okra mucilage and 0.75% chitosan and samples coated with 18% okra mucilage and 0% chitosan respectively.

 The aim of this project was to reduce the oil absorption of fried potato strips by coating them with chitosan and okra mucilage. Optimization to minimize the consumption of okra and chitosan mucilage showed that coating with 74% okra and 0.89% chitosan is suitable for coating potato slices. The desirability of this optimization was 71%, which is a reasonable percentage.

Grape seed oil is a rich source of omega-9 and omega-6 fatty acids, but the problems related to the production of food enriched with omega-9 and omega-6 fatty acids (the predominant essential fatty acids in grape seed oil) It is accompanied by the spontaneous oxidation of long chain fatty acids, which leads to a shorter shelf life, and due to their hydrophobic and unstable properties, they are difficult to dissolve in water and are easily oxidized, which leads to destruction and emergence The flavor becomes unpleasant. Therefore, it is necessary to develop effective delivery systems that can use grape seed oil in liquid foods more effectively. Recently, the preparation of emulsions using the layer-by-layer (LBL) method has received a lot of attention due to its various advantages, including the complete encapsulation of lipids, preventing the attack of peroxides and controlling the release of bioactive compounds. To prepare multilayer emulsion, grape seed oil was added to 1% gelatin solution and homogenized with a homogenizer. For the secondary emulsion, the primary emulsion was mixed with 2% chitosan solution and homogenized with a homogenizer after adjusting the pH. To prepare a three-layer emulsion, basil seed gum solution was added to the double-layer emulsion and homogenized again. Then, the particle size, viscosity, zeta potential, turbidity and refractive index, peroxide and thiobarbituric acid index of the samples were checked during one month of storage at two temperatures of 4 and 25 . The results showed that the maximum stability of single-layer, double-layer and three-layer emulsions was at pH 5, and the stability increased with the increase in the number of layers of grape seed oil multilayer emulsion. In fact, at this pH, gelatin, chitosan, and basil seed gum have negative, positive, and negative charges, respectively, and strong electrostatic interactions occur between biopolymers, after which LBL emulsions become stable. After the one-month storage period of emulsions, the particle size, viscosity, turbidity, refractive index, peroxide and thiobarbituric acid value have increased. Also, during the one-month storage period, by examining the physicochemical parameters (particle size, viscosity, zeta potential, turbidity and refractive index), the stability of emulsions at refrigerator temperature was higher than at ambient temperature. The results show that chitosan and basil seed gum can be used to form coating layers around fat droplets such as food emulsions, which can inhibit lipid oxidation and increase the stability of essential unsaturated fatty acids. Also, after study of the physicochemical and physical stability examination, it was found that the three-layer emulsion was more effective in maintaining these characteristics over time than the other two emulsions.

The rate of spoilage and oxidation in fish and the change in color of fish tissue, its shelf life is limited; therefore, it is necessary to use natural antioxidants to delay, control or inhibit these adverse reactions and prevent the reduction of food quality. The current study was conducted to determine the effect of chitosan-based edible coating containing Dunaliella alga extract on preservation the quality of fresh Huso huso fillet during storage in refrigerator. Microbial and chemical tests including total bacterial load and saline bacteria, pH, TBA as well as sensory evaluation were performed periodically for all samples and for algae extract, antioxidant activity was measured by DPPH method. The total bacterial count on the 10th day of storage for samples coated with algae extract was 6.17±0.22 log CFU/g, which was in the acceptable range for human consumption, but in control samples was 9.41±0.20 log CFU/g on the 10th day, which is beyond the permissible limit. The amount of psychotropic bacteria for the control treatment significantly (p<0.05) increased compared to the chitosan-coated treatment containing the extract. The values of pH and TBA in the control sample were significantly higher compared to the treated sample on the 5th and 10th days of storage (p<0.05). This study showed that the growth of bacteria in fresh fish fillets can be prevented by using chitosan coating containing algae extract, and its sensory characteristics, including texture, smell, color, and general acceptability, have been preserved to a great extent and increased the period of keeping fish in the refrigerator.

In this study, the effect of nanoparticles on oxide at three levels of 1, 3 and 5% was added to polylactic acid and chitosan nanocomposites and the results of its SEM (electron microscope) evaluation were evaluated and showed films containing polylactic acid and chitosan. It had an irregular and compact structure and with the addition of nanoparticles on oxide, it had a regular and cohesive structure. And water vapor permeability showed a significant effect (P <0.05). The results of histometry showed that with increasing the concentration of nanoparticles, the tensile strength of the film and the nanocomposite coating was significantly lower than the control treatment (P <0.05). Also, large changes in length to break point did not show a statistically significant difference. The results of tissue stiffness of this study also showed that during the 15-day storage time, the test treatment had the highest amount of stiffness. The effect of film and coating of nanocomposites based on polylactic acid and chitosan containing nanoparticles on zinc oxide on microbial properties indicated that during the shelf life of bread containing polylactic acid and chitosan dimers has an inhibitory effect on fungal growth by increasing nanoparticles on zinc oxide. Increases significantly. It also showed that the shelf life of seven sliced ​​toast containing the mentioned variables was higher at 5% level compared to the control treatment.

The consumer demand to use natural preservatives in food products instead of synthetic ones and awareness about not using plastic is increasing. In this research, chitosan-potato starch film containing celery seed extract was prepared at different concentration levels (0.5, 2 and 8%) and the physical properties of the film (thickness, moisture content and solubility), mechanical properties and antioxidant activity also determined. Then, the chicken fillet wrapped by the film was kept in the refrigerator for 15 days and the microbial growth and primary and secondary oxidation compounds formation with peroxide value and thiobarbituric acid and sensory evaluation was also monitored during the storage time. The results showed that the total phenol and flavonoid content of celery seed extract was 70.67±7.8 mgGA/g of extract and 62.81±5.65 mg Quercetin/g of extract, respectively. Addition of celery seed extract (2 and 8%) decreased the moisture content and solubility of the film due to the increase of the film hydrophobicity. Also, by adding the celey seed extract, the elongation at break of the film increased, while the tensile strength and elastic modulus decreased. With the increase in the concentration of the celery seed extract in the film, the DPPH free radical inhibition increases from 14.69 to 73.94%. According to the results of microbial and oxidation tests as well as sensory evaluation, coating a chicken fillet with a chitosan-potato starch film containing 8% celery seed extract would increase its shelf life by up to 15 days.

To investigate the effect of molecular weight of chitosan and the type of plasticizer used in the composition of edible coating on internal quality parameters and morphology of eggshell, an experiment with 125 eggs in a completely randomized design with 5 treatments included uncoated eggs (control), coated based on chitosan with high molecular weight (450 kDa) or low molecular weight (65 kDa) and the use of glycerol or sorbitol and 3 replicates was conducted. Coating was done by immersion method and the eggs were stored at ambient temperature for 4 weeks. The internal quality parameters of eggs including weight loss (WL), Haugh unit (HU), yolk index (YI) and albumen pH were evaluated weekly. At the end of the storage period, scanning electron microscope (SEM) micrograph were prepared for eggshell morphology. The results showed that the edible coating based on chitosan improved significantly (P<0.05) all the evaluated parameters. At the end of the week 4, among these, the lowest values of WL (7.01 ± 0.90) and pH of albumen (8.90 ± 0.15) and the highest values of HU (± 3.23) 63.80) and YI (0.34 ± 0.06) were seen in eggs containing high molecular weight chitosan-sorbitol coating (P<0.05). In the SEM micrograph, more integrated and less porous and fractured in the mentioned group. Therefore, in order to improve the quality of edible coating based on chitosan as a biocompatible packaging to increase the storage time of eggs, chitosan with higher molecular weight and sorbitol as plasticizer are recommended.

Increasing and improving the stability of colors in food during processing and also controlling the release until consumption is one of the most important issues and challenges in the use of natural colors in food. Hence, the objective of this study was to produce phytocyanin-containing nanoliposomes coated with chitosan by thin-layer ultrasonic hydration method to increase the stability of phycocyanin and to investigate its physical properties and encapsulation efficiency during storage. In this study, phycocyanin was coated with different concentrations of chitosan (0, 0.1, 0.2, 0.4, and 0.6 mg/mL) and stored at two temperatures (4 and 25° C) for 28 days. Then, to determine the best concentration of chitosan for coating the nanoliposomes, encapsulation efficiency, particle size, and zeta potential tests were performed. The results revealed that by increasing the concentration of chitosan to more than 0.2 mg/mL, no significant change in encapsulation efficiency was observed (p> 0.05). The sample without chitosan had the lowest particle size which was not a significant difference from samples containing 0.2 and 0.4 (p> 0.05). Increasing chitosan in the coating of nanoliposomes has led to increased zeta potential. Finally, a sample containing 0.2 mg/mL chitosan was selected as the best sample. Findings from analyses performed during the storage of nanoliposomes showed that nanoliposomes containing phycocyanin, which did not have any chitosan coating, had the highest encapsulation efficiency. On the other hand, it was found that with increasing storage temperature and storage time, the encapsulation efficiency decreased but the particle size increased. The lowest zeta potential of the samples was related to the phycocyanin-free nanoliposome sample which did not change significantly until the 21st day of storage at 4 °C. Scanning electron microscopy (SEM) images of the samples also confirmed the results of particle measurements.

Shrimp are highly perishable due to the biochemical, microbiological or physical changes during Post-mortem storage, which results in limited shelf life of the product (Farajzadeh et al., 2016). Melanosis is considered a limiting factor for crustacean preservation. This alteration originates by the action of polyphenol oxidase and in some species, as deep-water rose shrimp, also by the action of activated hemocyanin (Martínez-Alvarez et al., 2020). Traditional methods for shrimp preservation such as cold storage, freezing and chilling can’t suppress effectively spoilage (Farajzadeh et al., 2016). Hyssopus officinalis, as valuable medicinal herb, is widely used in traditional medicine. Due to the increased resistance of pathogenic microorganisms to antibiotics and increasing of treatment costs, attentions has been focused to compounds of natural origin (Pirnia et al., 1399). Nano-applications are named as one of the novel methods, which provide high immobilization efficiency for essential oils (keykhosravy e al., 2020). The nanoemulsion is a stable delivery system with unique physicochemical and practical characteristics including high physical stability, optical transparency and high bioavailability (khanzadi et al., 2020). In this study, the effects of chitosan nanoemulsion coating containing Hyssopus officinalis essential oil were investigated on melanosis phenomenon and color evaluation of shrimp samples during 12 days at 4 °C.

First, Hyssopus officinalis essential oil was prepared; Hyssop oil was extracted separately by water distillation. The essential oils components were identified by GC/MS (Pirnia et al., 1399). This study includes two phases of edible coating preparation and food modeling. After preparation of chitosan nanoemulsion containing essential oil, particle size and PDI were determined (keykhosravy e al., 2020). A dynamic light scattering (DLS) device (Malvern Instruments Ltd., United Kingdom) was utilized to measure the particle size of the nanoemulsion droplets. The distribution of droplet size was considered in the terms of the mean droplet size (z-diameter) and polydispersity index (PDI) (Moghimi et al., 2016). Then, Shrimp samples were provided and they were immediately placed in insulated polystyrene ice flasks and transported to the laboratory of food hygiene, Ferdowsi university of Mashhad, Mashhad, Iran. The fillets were washed completely for removing external particles (Mohajer et al., 2021). Shrimp samples were randomly divided into ten groups:CON: without any coating solutionCH: Chitosan coatingSCH: Sonicated Chitosan coatingSMS: Sodium Metabisulfite coatingHEO 0.5%: Hyssopus officinalis essential oil (HEO) 0.5% (W/V)HEO 1%: Hyssopus officinalis essential oil (HEO) 1% (W/V)CE+HEO 0.5%: Chitosan coarse emulsion coating containing 0.5% (W/V) HEOCE+HEO 1%: Chitosan coarse emulsion coating containing 1% (W/V) HEONE+HEO 0.5%: Chitosan nanoemulsion coating containing 0.5% (W/V) HEONE+HEO 1%: Chitosan nanoemulsion coating containing 1% (W/V) HEO The prepared samples were covered with different solutions for 2 min and were allowed to drain for 1 h. All the samples were placed into zip packs. Lastly, the samples were kept at 4 ± 1 °C for 12 days and analyzed for color evaluation and melanosis during 2/4-day intervals (days 0, 2, 4, 8 and 12). Lightness (+L), yellowness (+b), and redness (+a) of samples were measured with a Hunterlab colorimeter (Hunter Associates Laboratory, Inc., Reston, Virginia, USA), using a CIELab scale (Salehi et al., 2018). Whiteness (W) was also calculated, as described by Park, 1994 (Park et., 1994). Melanosis or black spot of shrimp was performed based on ocular evaluations (Sani et al., 2017). First, the basic sensory evaluation techniques and characteristics of shrimp meat (taste, smell, color, and texture) were introduced to the members of the group. 21 evaluators (20-38 years) were selected from among the staff and students of the Food Hygiene Laboratory of the Faculty of Veterinary Medicine, Ferdowsi University of Mashhad. The evaluators evaluated the samples in individual panels with sufficient light and randomly. For each evaluator, drinking water was placed for the intervals between testing the samples (keykhosravy et al., 2021). Sensory evaluation was performed using a 4-point scoring technique. In this method, a score of four indicates the absence of black spots on the shrimp and a score of one indicates the presence of black spots across the surface of the shrimp.

33 compounds were identified in Hyssop. Most of its compounds include isopinocamphen (35.45%), pinocamphen (11.81%) and beta-pinene (10.12%). The results are in agreement with Najafpour et al. (2001) and Fraternale et al. (2004). The z-diameter and PDI values of CE+HEO 0.5% were determined to be 570.3 ± 15.83 nm and 0.63±0.07, while for CE+HEO 1% were 402.2 ± 2.50 nm and 0.50±0.05, respectively. Z-diameter of the NE+HEO 1% and NE+HEO 0.5% were measured as 385.7 ± 3.09 nm and 538.9 ± 4.40 nm, and their PDI values were 0.55±0.03 and 0.76±0.01, respectively. Color is the most important visual feature for consumers in seafood. A value is infinite and positive values are equivalent to red and negative values are equivalent to green. B values are infinite and positive values are equivalent to yellow and negative values are equivalent to blue, and L index is equal to the brightness of the image which is between 0 zero equivalent to black and 100 Equivalent to full reflection of light (Salehi et al., 2018). On day 12, the lowest amount of redness and yellowness was observed in the groups of chitosan nanoemulsion containing Hyssopus officinalis essential oil (1% and 0.5%) compared to the control group. The brightness of the samples decreased with increasing storage time in all treatments; one of the reasons for this decrease is due to the appearance of black spots. Chitosan nanoemulsion treatment containing Hyssopus officinalis 1% had the highest score and control, chitosan and sonicated chitosan treatments had the lowest score in terms of melanosis by the end of the period compared to the control.

According to the results of this study, chitosan nanoemulsion coating containing Hyssopus officinalis essential oil can maintain the color index in shrimp meat compared to the control group and improve its color and replace synthetic compounds such as sodium metabisulfite as an anti-melanosis compound.

The purpose of this research was to enrich apple leather with pomegranate seed oil encapsulated with chitosan-soy isolate protein particles and to further investigate the color, texture and organoleptic properties of apple leather. At first, chitosan-soy protein isolate complex particles were prepared and then they were used to stabilize pomegranate seed oil emulsions (20, 30 and 50% oil). The results of the creaming index showed that the 20% emulsion had the lowest amount of creaming index after 14 days of storage. Next, the droplet size and viscosity of the 20% emulsion were evaluated. The results showed that the size of the emulsion droplets was about 1 µm and the flow behavior of the emulsion was Newtonian. Then, the effect of pomegranate seed oil emulsion (0.2, 0.5 and 1%) on the color, texture and organoleptic properties of apple leather was investigated. The results of the sensory evaluation showed that the apple leather without emulsion had a lighter color compared to the samples with a higher percentage of emulsion. The overall acceptability of apple leather for the control and the sample with 0.2% emulsion was not significantly different, and therefore it can be said that the use of pomegranate seed oil in apple leather in the form of emulsion up to 0.2% is suitable.

The aim of this study was to investigate the antimicrobial and antioxidant effects of chitosan edible film containing nanoemulsion of Melissa officinalis L. extract and Bunium persicum essential oil on Listeria monocytogenes inoculated into camel meat. The studied films were prepared using 2% chitosan and 2.5% and 5% of nanoemulsion of Bunium persicum essential oil and 4% of Melissa officinalis L. extract. The antimicrobial and antioxidant effects of coated camel meat during 16 days of storage at 4 °C with a 4-day interval (0, 4, 8, 12, 16) were evaluated. The coated portions were chemically evaluated. Most of the essential oil compounds include: cuminaldehyde (24.37%), γ-Terpinene (19.99%), and P-cymene (9.71%). The MIC of Melissa officinalis L. extract and Bunium persicum essential oil against L. monocytogenes were 1% and 0.25%, respectively. The antioxidant effects of films by DPPH method showed that the addition of essential oils and extracts increases the antioxidant properties of films. The antimicrobial effect of films by disk diffusion method, the largest diameter of growth inhibition zone (17.15 ± 0.16) was related to chitosan film containing 5% Bunium persicum essential oil and 4% Melissa officinalis L. extract. The average count of L. monocytogenes in the control treatment was higher than the other treatments. The results of TBARS showed that the antioxidant properties of films containing Bunium persicum essential oil and Melissa officinalis L. extract was higher than the control sample. The pH level in the samples coated with chitosan film containing 5% Bunium persicum essential oil and 4% Melissa officinalis L. extract was lower than the other treatments. In general, the prepared films have good antimicrobial and antioxidant properties against L. monocytogenes, which increase with the addition of plant compounds.

In this study, the effect of bilayer edible coating of gelatin-chitosan containing nanoemulsion of Perovskia abrotanoides Kar. essential oil on growth control of Aeromonas hydrophila inoculated into rainbow trout fillets over a 12-day period at 4 °C was investigated. The chemical composition of the essential oil was evaluated by GC-MS, its antibacterial properties by disk diffusion, plate well and micro-dilution broth, and its antioxidant properties by DPPH.Treatments included control, gelatin, chitosan, gelatin+essential oil, chitosan+essential oil and gelatin-chitosan+essential oil. After preparation, the treatments were packed in sterile polyethylene bags in laboratory conditions and stored for 12 days at 4 °C and their microbial, chemical and sensorial properties were evaluated every 3 days. The results of GC-MS showed that eucalyptol (24.51%) and camphor (22.02%) are the main components. The MIC and MBC of Perovskia abrotanoides Kar. essential oil nanoemulsions were reported to be 0.0625 and 0.125%, respectively. The amount of TVB-N and POV increased during the study period. According to the results of POV and pH measurements, there was a significant difference between all treatments and control treatment (P<0.05). The mean reduction log of bacteria was significantly different between all treatments and the highest antibacterial effect was observed in the gelatin-chitosan coating containing nanoemulsion of Perovskia abrotanoides Kar. essential oil. According to the results, Perovskia abrotanoides Kar. essential oil has good antioxidant and antimicrobial properties and according to the test results, it was found that chitosan-gelatin coating containing nanoemulsion of  Perovskia abrotanoides Kar. essential oil has an effective antimicrobial effect against Aeromonas hydrophila and can protect sensory properties and increase shelf life of rainbow trout fillets as well as useful coating to increase the shelf life of food products.

In recent years, the using of natural materials, along with the using of new technologies, which, in addition to increasing the shelf life, maintain the quality properties and nutritional value of the products, it has become doubly important. The results showed that increasing the duration of storage caused a decreasing in moisture, pH, anthocyanin, phenol, colorimetry and increased weight loss and acidity, the most effect was observed in 21 days of storage. The using of edible coating containing nanochitosan/pectin and S. officinalis decreased weight loss and antioxidant activity and increased anthocyanin, phenol and colorimetry. In 7 days after storage, the least weight loss was 2.3% and in 14 and 21 days after storage, the least weight loss was 4.25 and 5.86% in the treatment of 70 mg/lit pectin with 30 mg/lit of nano chitosan. According to the obtained results, the using of edible coating containing nanochitosan/pectin and S. officinalis especially the treatment of 70 mg/lit of pectin with 30 mg/lit of nano-chitosan, had the most effect in increasing the shelf life of black grapes.

Grape is one of the most important fruits in the world and despite being non-climacteric, its quality decreased rapidly. The main goal of post-harvest technology is to reduce losses during the post-harvest period. Different methods have been proposed to increase the shelf-life of fruits and vegetables, mainly including the use of chemical preservatives that have problems and limitations. Nowadays, demand for using natural compounds including active edible coatings for keeping fruits quality has increased. This study was conducted to investigate the effect of maltodextrin edible coating containing different concentrations of chitosan and olive leaf extract on shelf-life and quality attributes (including total soluble solids, fruit juice pH and acidity, flavor index, total phenolic compounds, vitamin C and organoleptic properties) of black grape fruit (Rasheh variety) during 90 days of storage period. Results showed that using maltodextrin coating containing chitosan and olive leaf extract reduced weight loss and prevented the degradation of phenolic compounds and vitamin C of samples during storage period. Increasing storage time resulted in a decrease in the amount of acidity and increased pH of samples, while increasing chitosan concentration and olive leaf extract increased the maintains of organic acids and decreased the pH of grape samples. The amount of total soluble solids in grape samples increased with increasing storage time. Results showed that the use of maltodextrin coating containing chitosan and olive leaf extract maintained the quality and reduced the degradation of the sensory properties of grape fruit during storage period. The best conditions for storing grape fruit include maltodextrin coating containing 2% chitosan and 0.75% olive leaf extract. At these conditions, storage time is about two months (57.30 days) and in this period, grape fruit has the minimum weight loss, but vitamin C and total acceptability are maximum, the desirability of these optimum conditions is 0.703.