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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. [ABSTRACT FROM AUTHOR]

The increase in the need for starch in the food processing industry has led to the recognition of the effect of other food compounds on the processing of starch-based foods. Xanthan and sugar are commonly used as hydrocolloids and sweeteners, respectively, in starch-based foods. These constituents can affect the structural, thermal, adhesive (dough) and rheological properties of these types of foods. The purpose of this study is to analyze the effect of sucrose and xanthan on the physicochemical, rheological and morphological characteristics of starch pastes. In addition, the comparison of the effect of the combination of xanthan and sucrose on corn and wheat starch pastes has been done in this study. In this research, the concentration of xanthan was 1% by weight and sucrose was 5% by weight, and the mixtures were prepared based on starch (corn or wheat starch). The results showed that in the presence and absence of xanthan 1% by weight and sucrose 5% by weight, the starch dough had a significant difference in terms of solubility, swelling power, water absorption, and dough transparency (p < 0.05). Rheological tests revealed that all pastes exhibited shear thinning behavior. By adding xanthan and sucrose, the apparent viscosity, storage modulus and loss modulus of starch pastes increased. Fourier transform infrared spectra showed the change in the intensity and wavelength of absorption peaks due to the addition of xanthan and sucrose. The measurements of scanning electron microscope and X-ray diffraction proved that as a result of adding xanthan and sucrose during gelatinization, changes were made in the network structure. The results of this study can improve processing and find optimal processing conditions to produce food based on Starch like baby food, bread, sweets, etc. help. [ABSTRACT FROM AUTHOR]

The use of quinoa seeds and its derivatives in the bakery products formulation, in addition to improving the nutritional value of the final product, reduces dependence on plant sources with high water requirements such as wheat and rice, so in this study the effect of rice flour replacement by whole quinoa enzymatic malt at levels of 0, 2.5, 5, 7.5 and 10% on physicochemical and textural properties and internal structure of gluten-free bread was investigated. The results showed that by increasing the amount of quinoa malt (up to 10%) in the product formulation no significant effect on moisture content and water activity was observed. However, the firmness of the texture in 2 and 72h after baking increased by 10% of quinoa malt. Also, the specific volume and porosity of the product was reduced only at level of 10% of quinoa malt flour. On the other hand, by increasing the amount of quinoa malt flour, the enthalpy of the samples decreased (2 and 72h after baking), while the enthalpy increased with increasing product storage time. The results of crust color evaluation showed a decrease in the amount of L* value and an increase in the amount of a* and b* values by increasing the amount of malt flour in the formulation, which indicates more turbidity of the product. The results of images obtained by Scanning Electron Microscope showed the average values of diameter and pore area of the product decreased by addition quinoa malt. Finally, the panellists gave the highest overall acceptance score to three samples containing 0, 2.5 and 5% of quinoa malt, which indicates the improvement of quantitative and qualitative properties of the final product using enzymatic derivatives and gluten-free quinoa. [ABSTRACT FROM AUTHOR]

Collagen is the most abundant protein of animal origin and the most important compound in the connective tissue which is widely used in the food and beverage industry. In addition, recent research has demonstrated the functional, beneficial, and potential properties of collagen extracted from aquatic wastes as nutraceuticals and for delivery systems of sensitive bioactive compounds. Therefore, the aim of this research was considered to study the structural charachters, antioxidant and functional properties of collagen and collagen hydrolysate extracted from the skin of common grouper (Epinephelus coicoides). In the present experimental study, the collagen sample was extracted by acid and enzymatic method and structural characters were studied by Fourier -transform infrared (FTIR) spectroscopy, Scanning Electron Microscope (SEM) and polyacrylamide gel electrophoresis (SDS -PAGE). DPPH radical scavenging, reducing Power and foam producing capacity also assessed.The results of Scanning Electron Microscope confirmed schistose structure, filamentus network, secondary and third structure, and the good interconnection and uniform porus matrix was noticed. The typical characters for type I collagen, including five peaks (amide A, amide B, amide I, amide II and amide III are observed in the spectrogram of collagen and collagen hydrolysate, also the preserved triple -helical structure were comfirmed. The results of the functional properties and antioxidant activity of collagen from orange -spotted grouper skin also showed that with increasing the concentration, reducing power and DPPH radical scavenging ability increased. Comparing collagen and hydrolyzed sample, the foam producing capacity was proved just for collagen. Finally, it can be said that collagen and hydrolyzed collagen extracted from the skin of orange -spotted grouper with suitable antioxidant properties, and appropriate functional properties can be mass -produced as a bioactive compound and as emulsifier may be used in the food industry and in the production of Functional foods. [ABSTRACT FROM AUTHOR]

The musk willow essential oil is volatile and encapsulation can protect them from environmental factors such as, light, oxygen and temperature. In the present research, preparation of sodium alginate -whey protein microcapsule containing essential oil of musk willow was carried out by internal gelation -emulsification method with encapsulation efficiency of 87.31%. The obtained microcapsules were characterized by particle size analyzer, zeta potential analyzer and scanning electron microscope. Encapsulation efficiency, swelling ratio and in vitro release of the essential oil was also investigated in fatty and acidic food simulationconditions. At acidic and fatty food simulation conditions, the complex presented negatively charged, with potential zeta values being 42.25 and 38.11 mV, respectively. The greatest electrostatic interaction occurred near pH 3.0 where the charge approached neutrality, which represents a balance between the biopolymer charges. Microcapsules shrinking in the acidic food simulation (pH=3.0) and expanding in the fatty food simulation (pH=7.0). The release results indicated that the release of musk willow essential oil from the microcapsule in both conditions occurred with a controlled manner and exhibited a slow rate. The essential oil release was found to be best fitted by Hixson–Crowell model (R 2 =0.993 for the acidic food simulation condition and R 2 =0.995 for fatty food simulation condition) which implies that a change in diameter of the microcapsule as a function of time. Mathematical modeling of release kinetics shows that musk willow essential oil loaded microsphere release follows by classical Fickian diffusion and erosion/degradation mechanisms. [ABSTRACT FROM AUTHOR]

Background and Objective: Microplastics can have harmful effects on living things, including humans. These particles have been identified in all water, soil, and food sources. Among these, freshwater resources are more important, because they are considered a water source for humans through drinking water treatment plants (DWTPs). Therefore, this study investigates the performance of Tehran DWTPs in removing these particles. Materials and Methods: In this study, the performance of three DWTPs in Tehran in removing these particles was investigated. In most studies worldwide, particles larger than 1 µm were examined, but in this study, nanoplastic particles smaller than 1 µm, as well as the effect of the warm and cold seasons of the year on the concentration of these particles were also examined. Results: According to the results of the study, the amount of micro and nanoplastic particles at the inlet of treatment plants in the warm season of the year was 2569 ± 309 to 3918 ± 425 MP/L, and the output was 1492 ± 32 to 2279 ± 146 MP/L, which indicates an increase in these particles in the warm season. As a result, the studied treatment plants were only able to remove 32.1 to 59.9% of these particles. In addition, using electron microscopy, MPs were classified into three categories in terms of appearance: fiber, fragment, and film. This study completes the knowledge of MPs in this area. Conclusion: Based on the results of this study, Tehran DWTPs have poor performance in removing these particles. [ABSTRACT FROM AUTHOR]

With increasing public awareness, the demand for healthy foods has increased. Low resistance of probiotic bacteria against adverse environmental conditions is one of the most important factors limiting the production and development of probiotic products. Encapsulation by enclosing probiotic cells can increase stability against limiting factors such as gastric acidity.In this study, the efficiency of double layer encapsulation with sodium alginate and chitosan by spray drying and emulsion methods on the stability of Lactobacillus acidophilus under simulated gastric conditions (pH=2) during 0, 30, 60, 90 and 120 minutes were examined. The size of the microcapsules was determined by the particle size analyzer and their morphology using a scanning electron microscope (SEM).The obtained growth curve showed that the bacteria enter a stationary growth phase 40 to 42 hours after inoculation. The size of the microcapsules obtained from the emulsion method were significantly (p≤ 0.05) smaller than the spray drying method. The morphology of the microcapsules was spherical to oval, and the samples obtained from the spray drying method had a shrinked surface. The highest survival was shown by emulsion encapsulated samples with a decrease of 1.9 logarithmic cycles, followed by spray dried encapsulated bacteria with a reduction of 2.4 logarithmic cycles. The lowest survival rate was related to the control sample (free bacteria) with a decrease of 3.83 logarithmic cycles.Encapsulation of Lactobacillus acidophilus probiotic bacteria by the emulsion technique by creating appropriate stability under simulated gastric conditions is a suitable method to obtain probiotic products enriched with this bacterium. [ABSTRACT FROM AUTHOR]

Introduction: Nowadays, the heavy metals pollution is one of the most important environmental problems. Due to the high cost of common refining methods, the use of microbial biomass is recommended to clean up heavy metals. The aim of this study was to evaluate the interactions of Rhodoterula toruloides strain IR-1395 with mercury. Materials and methods: In this study, the growth rate and types of interactions of the strain IR1395 with mercury in the Sucrose Broth medium were investigated and the amount of mercury accumulated was measured using the Spectrophotometry method. Then, in order to determine the best biosorption conditions, the effect of parameters such as pH, mercury concentration, biomass concentration, contact time, and the temperature was measured. Also, the biosorption was investigated by treated cells with 2,4 dinitrophenol and autoclave. Finally, the biosorbent was characterized by Scanning Electron Microscope equipped with Energy Dispersive X-Ray Analysis. Results: Studies have shown that the maximum growth rate of the strain IR-1395 was after 36 hours and then it entered the stationary phase. Also, this strain was able to the biosorption and bioaccumulation (61.86%) and 10.17% biovolatilization of mercury from the medium at the concentration of 10 mg/l of chloride mercury for seven days. In examining the factors affecting the mercury biosorption, it was indicated that the optimal pH was 4. The highest biosorption was observed at 300 mg/l of mercury in 10 minutes at 15 ˚C. In the study of the effect of 2,4- dinitrophenol treatment and autoclave, it was found that mercury adsorption has reduced by the treated yeast. Finally, the results of the EDX confirmed the biosorption of mercury by this yeast. Discussion and conclusion: By examining the types of interactions of the strain IR-1395 with mercury and its potential in biosorption, it was found that this strain is a valuable microorganism in mercury bioremediation processes from contaminated aquatic environments. [ABSTRACT FROM AUTHOR]

Kaymak or Sarshir, a traditional dairy product, is served in Iranian breakfast. The aim of this study was to investigate the fatty acids profile, physicochemical properties (texture, color, pH, acidity, the content of dry matter, fat and protein) and organoleptic aspects of Gilanvand and Dalirankaymaks in comparison to the heavy cream. To study more closely the texture and appearance differences of these products, scanning electron microscope (SEM) images were also prepared. The obtained results showed that the contents of fat and dry matter in heavy cream were higher than the kaymaks; however, Gilanvandkaymak had the highest protein content, acidity, and b*-value. Based on the study of the fatty acids profile, palmitic acid and cis-oleic acid were recognized as the most dominated saturated and unsaturated fatty acids, respectively. Microstructural analysis of SEM revealed that the structure of the protein in the fat field was compact, irregular and abundant in Gilanvandkaymak which influenced the product properties. The hardness, gumminess, and adhesiveness of the heavy cream were highest in comparison to the kaymaks. The Gilamvandkaymak obtained higher scores in evaluating the taste and total acceptance. In conclusion, it can be mentioned that the Gilamvandkaymak will have high potential in marketability by considering its higher protein content as well as total acceptance. [ABSTRACT FROM AUTHOR]

One of the reasons for soil salinization is the accumulation of salts in it by transmission through water and wind. In order to investigate the phenomenon of transfer of salts with dust in the arid regions of the north of Yazd- Ardakan plain, field samples were taken using 32 MDCO sediments traps with uniform dispersion in an area of 20,000 hectares at some stage in 4 seasons of 2017. After washing the sediment collector with a liter of distilled water in the field and transferring the samples to the laboratory, for the quantitative analysis of saline dust, similar to measuring the Water Electrical Conductivity (ECw), the Total Soluble Solids (TDS) were additionally measured through evaporation technique. The form and distribution of the dust particle size were additionally investigated using a Scanning Electron Microscope (SEM) tool. Within the qualitative examine of salts, effective cations and anions in salinity including Na+, K+, Ca++, Mg++, Cl, HCO3and SO4were measured The results confirmed that, in general, the fallout was 11.1 g.m2 of soluble material with dust particles (13.28%) in the course of only 12 months. Particles with a diameter of 5 to 10 microns were the most frequent. Considering the high correlation between Cland Na+ in the spring, autumn and winter, due to the high correlation between Ca++ and SO4in summer dust, sodium chloride (NaCl) and gypsum (CaSO4) 2H2O)), the most abundant composition of dust- containing salts could be expected in these seasons. By determining the percentage of solutes in the fallout dust, it was observed that the impact of the amount of the deposited salt from dust was slight and insignificant in the short time period; with the assumption of no change in the rate of subsidence, it was anticipated that it would explain the poor salinity in non- saline mass soils for up to 10 cm in 72 years. In general, the capability of airborne salt in increasing the soil salinity in the study area can be in long- term periods. Therefore, it is recommended to investigate other environmental effects of this phenomenon in order to identify its hazards. [ABSTRACT FROM AUTHOR]

In this research, pollen grains of some species of Grumorsae group of Ranunculus were studied. In doing so, pollen grains of 13 species were studied by light microscope and the surface of nine pollen grains has studied by Scanning Electron Microscope. Among these species, in addition to previous pollen types in the genus Ranunculus, a new type (Thalictrum flavum L.) was reported. Finally, we could distinguish the species based on pollen grains characters and prepare an identification key. [ABSTRACT FROM AUTHOR]