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关键词： Anodization and hydrothermal process   Acid (HCl) treatment   Fe-TiO2 nanotubes   Visible light   Degradation and reduction  

摘要： In this study, we prepared Fe2O3/TNT composite (Fe-TNT) foil by combining anodization with the hydrothermal method. Photocatalytic reaction was restricted by a cluster of iron particles accumulated on the foil surface and the photocatalytic reaction sites reduces. Herein, using XPS determined that these iron particles are composed of iron oxide. An acid treatment, hydrochloric acid (HCl) was used to successfully remove the surface accumulation of iron oxide particles on the photocatalyst. Using cleaned Fe-TNT foil, the photocatalytic activity of 5 mg/L Congo red (CR) and hexavalent chromium reduction was significantly increased under visible irradiation. In addition, the influence of different aspects such as pH, the concentration of Fe, and the effect of different acid treatment time was evaluated. Removing the surface accumulated iron oxide and adjusting the pH in acidic medium, 73% hexavalent chromium reduction achieved within 180 min. The reusability was also explored by monotonous CR degradation. The CR degradation using Fe0.25-TNT was lessened from 78% in the first cycle to 71% in the 3rd cycle. It was also confirmed experimentally that photocatalytic activity improvement of HCl treated Fe-TNT was not due to alternation in nanotube structure.

关键词： Moringa oleifera   Inoculum   Fortification   Syneresis   Organoleptic analysis   Yogurt  

摘要： The fermented foods are same as traditional food, in appearance and consumed as normal foods but have modified by the addition of certain pro & pre-biotics or fortification with the plant extract, which have specific physiological roles beyond just satisfying nutrition requirement. Fresh leaves of Moringa oleifera were collected from the field of Institutes of Agriculture Sciences, then dried and grounded. The proximate analysis of dried moringa leaf powder and milk was performed. In four different concentrations (0.5%, 1%, 1.5% and 2%) Moringa Oleifera leaf powder, was used for the production of fortified flavoured yogurt, while mango flavor and color was added to enhance its sensory characteristics. Physicochemical analysis (pH, acidity, ash, fat, protein, fiber, synersis, total solid content and moisture content) was done to check the yogurt nutritional profile and effect of moringa dried leaf powder on it. Sensory evaluation (body texture, appearance, color, taste, aroma, flavor and overall acceptability) is also done by expert panel of food scientist (n = 20) by using hedonic scale to check the acceptability and quality of *** check the product shelf life stability, product is stored at 5 +/- 1 oC for 15 days and observed for its physicochemical changes and sensory attributes. The sample were analyzed for their stablity as fresh and during storage interval of 10th day and 15th day. Results shows that mango flavored yogurt supplemented with 1% Moringa Oleifera leaf powder has got the highest score in majority of the sensory attributes such as body and texture, flavor, taste and overall acceptability over the storage period of 15 days at 5 +/- 1 degrees C. All treatment showed significantly different (p <= 0.05) result from each other. However, higher acidity%, total solids%, protein% and synersis value were observed, than control samples on 0 days (fresh), 10 days and 15 days storage, respectively. While all treatments have less pH and moisture content th

关键词： Rice bean starch   Heat moisture treatment   Retrogradation   Esterification   Acid alcohol modification  

摘要： Starch was extracted from the rice bean which is largely underutilized and modified by physical (i.e. heat moisture treatment and retrogradation) and chemical (i.e. esterification and acid alcohol modification) methods. Both, physical and chemical modifications significantly (p < 0.05) affected the physicochemical, pasting, particle size and morphological properties of rice bean starch. Both amylose content and swelling power reduced after physical and chemical modifications. Among modified starches, retrograded starch showed higher solubility (8.56%) at 90 degrees C. Retrogradation also resulted in higher values of water (251%) and oil absorption (106%) capacities in comparison to other modified starches. Physical modifications greatly influenced the pasting properties in comparison to chemical modifications. The particle size distribution followed the order: native starch (659.8 nm) > heat moisture treated (434.3 nm) > retrograded (355.4 nm) > esterified (218 nm) > acid alcohol treated starch (234.5 nm). The study revealed that the particle size of rice bean starch was reduced by both physical and chemical modifications. FE-Scanning electron microscopy was used to study the morphological characteristics of starches and it was observed that retrogradation had a pronounced effect on the starch granules morphology.

关键词： surimi gel   TGase‐   induced cross‐   linking degree   physicochemical properties   brittleness   network structure   Raman spectrum  

摘要： BACKGROUND The transglutaminase-induced cross-linking reaction can enhance the textural properties of surimi gels. However, when the cross-linking degree exceeds a certain range, surimi gels become brittle, giving the gel a special mouthfeel. Little information is to be found regarding the brittleness of surimi gel and its formation mechanism. The present study aimed to investigate the effects of cross-links on physicochemical properties of surimi gel and to analyze the reason for the textural variation of surimi gels regulated by cross-links. RESULTS When the cross-linking degree was lower than about 30%, the surimi gel could not be fractured and the surimi gel was mushy. When the cross-linking degree was around 40-55%, surimi gels without microbial transglutaminase (MTGase) presented an elastic texture, while surimi gels with MTGase displayed a tough texture. When the cross-linking degrees were 64.1% and 76.5%, surimi gels became brittle. Water holding capacity decreased with the increase in cross-linking degree and the cross-links released some combined water to free water. With the increase in cross-links, the pore equivalent diameter and the fractal dimension first decreased and then increased. When the cross-linking degree exceeded approximately 50%, hydrophobic interaction increased, consistent with the exposure of hydrophobic residues and the decrease in the water gap between proteins. CONCLUSION The changes in gel texture were related to micro-network structure, water status and microenvironment of proteins. It was demonstrated that the texture of slowly heated surimi-based products could be regulated by controlling the TGase-induced cross-links. (c) 2021 Society of Chemical Industry.

关键词： Thermal stability   Dielectric properties   Polyhydroxyalkanoate   Polylactic acid   Montmorillonite clay  

摘要： In this study, the electrical, thermal, morphological and physical properties of polyhydroxyalkanoate (PHA) and polylactic acid (PLA) blends and its nanocomposites prepared in different content of montmorillonite (3%wt, 5%wt, 7%wt) were investigated. Biodegradable blends of PHA/PLA were prepared in different compositions ranging from 30-70%. Nanocomposite films were analyzed by Fourier Transform Infrared (FTIR), Thermogravimetric Analysis (TGA), Differential Thermal Analysis (DTA) and scanning electron microscopy for morphology (SEM). The effects of the amount of MMT used as a reinforcing filler on the morphology, color, opacity, thermal stability, and dielectric properties of PHA/PLA films were investigated. SEM analyses showed good interaction between MMT and PHA/PLA film. As the MMT concentration increases, the transparency of the films decreases. In addition, MMT has improved thermal stability. Also, the dielectric properties and electrical conductivity of nanocomposite films were studied. The measurements were performed at frequencies between 100 Hz to 10 kHz at room temperature. As the frequency increased, dielectric permittivity (epsilon), the dielectric loss (epsilon'') and the electrical conductivity (sigma) decreased and remain constant at high frequencies. epsilon, epsilon'' and the sigma increased with increasing MMT content.

关键词： Edible coating   Lamb slices   Citrus paradise essential oil   Lallemantia iberica seed mucilage   Quality retention  

摘要： There is an increasing demand for bioactive-loaded bio-based packaging materials to obtain food products with extended shelf-life and improved quality. The aims of the present study were to fabricate a Citrus paradise essential oil (CPEO)-loaded Lallemantia iberica seed mucilage (LISM) based edible coating and to evaluate the effects of the CPEO-LISM edible coating on the preservation of lamb slices during cold storage for 9 days. CPEO was rich in limonene (79.4%) with superb antioxidant and antimicrobial properties. Its incorporation into the edible coating (at 0, 0.5, 1, 1.5, and 2% v/v) effectively inhibited the microbial growth (total viable count, psychrotrophic count, Escherichia coli, Staphylococcus aureus, and fungi) and lipid oxidation (peroxide and thiobarbituric values) in lamb slices. The meat color (L*, a*, b*) and sensory properties were also preserved by the edible coating containing CPEO, and the bioactive edible coating based on LISM and CPEO, particularly LISM + 2%CPEO significantly inhibited quality deterioration of lamb slices and improved the shelf-life of the meat (> 9 days). The results suggested that the LISM-CPEO edible coating could be developed as an antioxidant and antimicrobial packaging to improve the shelf-life of various meat products.

关键词： Virus protein to host membrane interactions   Quartz crystal microbalance with dissipation   Dynamic force spectroscopy   Total internal reflection fluorescence microscopy   Equilibrium fluctuation analysis   Single particle tracking  

摘要： The objective of this critical review is to provide an overview of how emerging bioanalytical techniques are expanding our understanding of the complex physicochemical nature of virus interactions with host cell surfaces. Herein, selected model viruses representing both non-enveloped (simian virus 40 and human norovirus) and enveloped (influenza A virus, human herpes simplex virus, and human immunodeficiency virus type 1) viruses are highlighted. The technologies covered utilize a wide range of cell membrane mimics, from supported lipid bilayers (SLBs) containing a single purified host membrane component to SLBs derived from the plasma membrane of a target cell, which can be compared with live-cell experiments to better understand the role of individual interaction pairs in virus attachment and entry. These platforms are used to quantify binding strengths, residence times, diffusion characteristics, and binding kinetics down to the single virus particle and single receptor, and even to provide assessments of multivalent interactions. The technologies covered herein are surface plasmon resonance (SPR), quartz crystal microbalance with dissipation (QCM-D), dynamic force spectroscopy (DFS), total internal reflection fluorescence (TIRF) microscopy combined with equilibrium fluctuation analysis (EFA) and single particle tracking (SPT), and finally confocal microscopy using multi-labeling techniques to visualize entry of individual virus particles in live cells. Considering the growing scientific and societal needs for untangling, and interfering with, the complex mechanisms of virus binding and entry, we hope that this review will stimulate the community to implement these emerging tools and strategies in conjunction with more traditional methods. The gained knowledge will not only contribute to a better understanding of the virus biology, but may also facilitate the design of effective inhibitors to block virus entry.

关键词： Fat replacement   Beef burger   Ethylcellulose   Unsaturated oil  

摘要： The aim of this study was to evaluate the physicochemical properties of beef burger after substitution of animal fat with the ethylcellulose (EC) oleogel. Therefore, sesame oil oleogels were prepared using EC in concentrations of 10%, and cooled at 25 degrees C. The fatty acid profile of EC oleogel compared with animal fat. Then, the EC oleogel was incorporated to hamburger at the 0, 25 and 50% instead of animal fat and color and textural properties as well as cooking loss, cooking shrinkage, fat absorption, and lipid oxidation of the beef burgers were evaluated. As an outcome, the EC oleogel contained high levels of linoleic and linolenic acids, while the palmitic and stearic acids were lower than the animal fats, and myristic acid was not detectable. Replacement of animal fat with EC oleogel upgraded the quality of final product by reducing cooking loss and fat absorption. Production of beef burger with EC oleogel decreased the oxidation process during frozen storage as well as cooking loss and fat absorption, and enhanced textural properties including chewiness and hardness. Improvement of nutritional and technological properties of hamburgers contained EC oleogel makes it a desirable candidate for animal fat substitution.

关键词： FTIR spectroscopy   UV–   visible spectroscopy   Electrical measurements   Surface morphology   Gamma-rays   PC   PBT  

摘要： In this study, blend of polycarbonate (PC)/polybutylene terephthalate thin films was used. This blend belongs to the class of polymeric solid-state nuclear track detectors. Blend samples were exposed to gamma-rays with different doses (55-355 kGy). The compositional changes, the changes of optical properties, the electrical parameters changes and surface morphology in the gamma irradiated samples were studied. Different techniques were used to study improving the physicochemical properties of the irradiated samples, such as Fourier transform infrared spectroscopy, UV-Visible spectroscopy, LCR Meter Bridge and scanning electron microscope, as well as, the roughness testing. Fourier transform infrared measurements exhibit that the degradation in the polymer chain occurs after irradiation with gamma-rays. This means that some functional groups are the most sensible groups to gamma-rays. UV-Visible spectra of the gamma exposed samples exhibited a shift in the absorbance edge toward the region of higher wavelength. This trend reflects a decrease in the band gap energy, which leads to an increase in the electrical conductivity of the samples. The outcomes of dielectric loss and dielectric constant are sensible parameters for whole frequency range to the changes in the structural and optical behaviors as a result to gamma irradiation. Additionally, the surface changes were discussed.

关键词： Uranium   Drinking water   Radiological & chemical risks   Effective dose   Punjab   India  

摘要： Present study is carried out in Tarn Taran district of Punjab state for the water quality assessment. The mean value of uranium is found to be 38 mu g L-1 with the variation of 0.9 mu g L-1 to 224.6 mu g L-1, where almost half of the samples are above the permissible limit (30 mu g L-1) given by World Health Organisation. Maximum value of total dissolved solids (TDS) observed in the water samples is 1365 mg L-1 which is quite higher than the recommended value (600 mg L-1). Correlation of uranium with other physico-chemical parameters has also been analysed. Carcinogenic and non-carcinogenic risks have been calculated along with age dependent mean effective dose.