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关键词： Low-sodium bacon   Bacterial community   Lipid oxidation   Proteolysis  

摘要： This work aimed to determine the effects of partial substitution of NaCl with 0% (control), 30%, 50%, and 70% of KCl on the bacterial communities, proteolysis and lipid oxidation of Chinese bacon during processing. The proportion of genus Lactobacillus increased from 22.45% (fresh meat) to 72.78%, 81.64%, 76.53% and 85.63% at the end of processing for 0%, 30%, 50% and 70% KCl replacement samples, respectively. During the processing, Lactobacillus gradually became the dominant one, and higher the KCl ratio, more rapid was the process. After salting, the TBARS of control was markedly higher (P 0.05) than that of the others, while a similar lipid oxidation level (P 0.05) was observed at the end of processing for different groups. After salting, there was no difference in total free amino acids (TFAA) content among four treatments (P > 0.05), whereas KCl replacement samples shared significantly higher (P < 0.05) values than control at the end of processing. Redundancy analysis and Pearson correlation showed positive correlation between Lactobacillus versus TBARS and TFAA. Partial replacement of NaCl with KCl could, directly or subsequently by promoting the growth of Lactobacillus, influence proteolysis and lipid oxidation over the manufacturing process.

关键词： Diphenyl carbonate   THP1 cell line   Biochemical assessment   Carbopol   Hydrogel   Oxidative stress  

摘要： Clobetasol propionate (CP), a superpotent topical corticosteroid, holds great promise for psoriasis treatment. However, common side effects like skin atrophy, steroidal acne, hypopigmentation and allergic contact dermatitis associated with it, hamper its utility for topical application. Taking this into consideration, the current work was aimed to fabricate CP loaded cyclodextrin nanosponge (CDNS) based hydrogel, to alleviate the aforementioned side effects, while controlling drug release. Nanosponges were crafted employing beta-cyclodextrin (polymer) and diphenyl carbonate (cross linker) and evaluated appropriately. The selected formulation augmented 45 folds water solubility, with respect to pure CP. The formulation possessed entrapment efficiency (56.33 +/- 0.94%), particle size (194.27 +/- 49.24 nm) with polydispersitive index (0.498 +/- 0.095), surface charge (-21.83 +/- 0.95 mV) and drug release (86.25 +/- 0.28%). Selected CP-CDNS were found crystalline and uniform in size. Further, in vitro cell viability analysis has been performed using THP1 cells to evaluate cytocompatibility of CP nanosponges. The chosen CP nanosponges were then embedded into Carbopol hydrogel, and characterized for rheological behaviour, spreadability, and texture profile. The developed nanoformulations were also assessed in vivo using mouse tail model. Histological and biochemical assessments have been conducted to explore their antipsoriatic activity via oxidative stress biomarkers. The degree of orthokeratosis was observed remarkably (p < 0.001) amplified by CP-CDNS14 hydrogel as compared to untreated group (control) and CP hydrogel. In addition, drug activity and change in epidermal thickness were found significant. Our findings altogether advocated the profound potential of prepared CP nanogel in the topical treatment of psoriasis, with improved patient compliance.

关键词： Fortification   Unsaturated fatty acids   Sensory analysis   Texture  

摘要： The influence of adding flaxseed oil (2.9-5.1%) and flaxseed-whey protein concentrate (WPC) emulsion (4.8-8.6%) to cream as an omega-3 fatty acid source was evaluated on the thermal, sensory and physico-chemical properties of the developed butter. Pulsed nuclear magnetic resonance analysis revealed lower saturated fat content in the fortified butter than control butter. Differential scanning calorimetry exotherms and endotherms also corroborated these findings. Fortified butter prepared with 6.8% flaxseed oil-WPC emulsion had 3.7 times more alpha-linolenic acid content than control and provided nearly 25% of the recommended dietary allowance in one serving. The developed butter exhibited improved spreadability.

关键词： consumer acceptability   kelp   Lactobacillus plantarum   texture   vegetable fermentation  

摘要： Consumption of nutrient-rich seaweeds and fermented nondairy foods represent fast growing trends among health-minded consumers. Assessment of lacto-fermented seaweed was performed to address these trends, and to offer shelf-life extension and product diversification for fresh kelps. The objectives were to evaluate the effects of kelp species and inclusion level on fermentation kinetics, physicochemical quality, safety, shelf-life, and consumer acceptability of a seaweed sauerkraut-style product. Six formulations with different inclusion levels (25, 50, and 75%) of shredded kelp (sugar kelp, SK or winged kelp, WK) were mixed with cabbage, 2% salt, and inoculated with Lactobacillus plantarum (approximately 10(6) CFU/g) and Leuconostoc mesenteroides (approximately 10(1) CFU/g). Products were processed in triplicate, fermented until a target pH of <= 4.6 was achieved, and sampled periodically for 60 days. Kelp species and inclusion level significantly affected most variables tested. The most rapid fermentation (3 days), as evidenced by pH decrease, lactic acid bacteria counts, and lactic acid levels, was noted in WK formulations. Some SK formulations took up to 14 days to achieve the target pH, and coliforms persisted to a greater extent in the SK formulations. Higher levels of kelp decreased the fermentation rate and concentration of fermentable sugars in the brine, but increased the total phenolic content and antioxidant activity of the sauerkrauts. Despite differences in instrumental color (L*a*b*) and texture (shear force) among formulations, overall liking as rated by a consumer panel was not significantly affected by species or inclusion level. Results support the use of lacto-fermentation in the production of refrigeration-stable seaweed sauerkraut-style product. Practical Application Health-conscious consumers are becoming increasingly interested in plant-based diets and fermented foods, and the development of novel seaweed sauerkraut-style products can help to

关键词： Photocatalytic activity   Particles size distribution   Air purification pharmaceuticals  

摘要： The presence of triple phase TiO2 new mixture (Magneli of higher order homologous series, brookite and anatase) containing P dopant ensures positive changes in the structure, in the phase composition and in the chemical composition. These changes explained the reasons for the enhanced UV/Vis photocatalytic efficiency towards oxidative degradation of ethylene and acetylsalycylic acid. The samples were characterized by a set of methods: Raman spectroscopy, Scanning Electron Microscopy (SEM), Diffuse-Reflectance Spectroscopy (DRS), Differential Thermal Analysis (DTA-TG), X-ray Photolelectron Spectroscopy (XPS), Transmission Electron Microscopy and High-Resolution Transmission Electron Microscopy (TEM/HRTEM), Electron Paramagnetic resonance (EPR) and X-ray Diffraction (XRD) analyses. The combination of the optimal set of values of Ti3+, oxygen radicals and vacancies, Ti-O-P bonds, narrower band gap is responsible for the higher quantum yield due to the increased number of charge carriers, while the unique phase mixture prevents the recombination of charge carriers. These factors guarantee enhanced rate of the photocatalytic reaction, and extended response to the visible light region.

关键词： Alginate   Spray-drying   Freeze-drying   Liposomes   Food ingredient   Stability  

摘要： Liposome entrapment is a promising technology in the food industry to provide protection or controlled/targeted release to both hydrophilic and lipophilic substances. However, liposomes are obtained in the form of suspensions which has some disadvantages with view to their use as food ingredients, namely, problems for storage, transportation, and formulation of low-to-intermediate moisture foods. So, the research on drying methods able to render dried liposomes with minimum structural changes is mandatory. In the present work, the ability of alginate as protective and carrier biopolymer during liposomal suspensions drying and rehydration was evaluated, as function of drying method (freeze-drying and spray-drying). Freeze-drying rendered sponge-like structures showing a loose porous matrix, whereas spray-drying rendered a powder composed of microparticles up to 20 mu m in diameter. Both of them showed a homogeneous white-to-creamy color as well as good wettability and water dispersibility, behaving as a light viscous material upon rehydrating which is compatible with most food products. Alginate provided protection to liposomes during drying and rehydration, as only minor changes in their size and shape were observed, however, multilamellar and multivesicular vesicles were formed. Furthermore, alginate also provided protection upon reconstitution at different pHs, contrary to what happened to fresh liposomal suspensions, whereas low-to-moderate thermal treatments had a negligible effect on size and stability. The use of alginate as carrier and protective agent for drying liposomal suspensions is promising with view to the extension of their use as food ingredient, for both freeze-drying or spray-drying methods.

关键词： Amylopectin   cluster   physicochemical properties   Potato starch  

摘要： In this study, yellow, red and purple potato starches were selected as the research objects to analyse the fine structure and the relation to the physicochemical properties. Enzymatic hydrolysis and high-performance anion-exchange chromatograph were employed to characterise the structure of clusters and phi, beta-limit dextrins. The average degree of polymerisation of clusters from the yellow potato starch was larger (188.57) than in red (91.31) and purple (107.32) potato starch. The molar percentage of fingerprint B chains in yellow, red and purple potato amylopectin were 58.01%, 63.60% and 60.78%, respectively, while major part of short B chains were 15.92%, 17.16% and 16.49%, respectively. The yellow potato amylopectin showed the highest density of branches values indicated that it was more tightly branched. The Pearson correlation coefficients results indicated that the fine structure of amylopectin had significant effects on the physicochemical properties of potato starches, and we can better understanding the differences of the properties among the three potato starches by studying the amylopectin fine structure.

关键词： Polymers   Chemomechanical properties   Antibacterial agents   Nanotechnology   Dentin bonding agents  

摘要： Objective. Formulate experimental adhesives containing titanium dioxide nanotubes (ntTiO(2)) or titanium dioxide nanotubes with a triazine-methacrylate monomer (nt-TiO2:TAT) and evaluate the effect of these fillers on the physical, chemical, and biological properties of the adhesives. Methods. First, nt-TiO2 were synthesized via a hydrothermal method. The nt-TiO2 were mixed with a triazine-methacrylate monomer (TAT) to formulate nt-TiO2:TAT, which were characterized by transmission electron microscopy (TEM). The nt-TiO2, TAT, and nt-TiO2:TAT were evaluated via Fourier Transform Infrared, Ultraviolet-visible, and micro-Raman spectroscopies. An experimental adhesive resin was formulated with bisphenol A glycerolate dimethacrylates, 2-hydroxyethyl methacrylate, and photoinitiator/co-initiator system. ntTiO(2) or nt-TiO2:TAT were incorporated at 2.5 wt.% and 5 wt.% in the adhesive. The base resin without nt-TiO2 or nt-TiO2:TAT was used as a control group. The adhesives were evaluated for antibacterial activity, cytotoxicity, polymerization kinetics, degree of conversion (DC), Knoop hardness, softening in solvent (AKHN%), ultimate tensile strength (UTS), 24 hand 1 yearmicrotensile bond strength (mu-TBS). Results. TEM confirmed the nanotubular morphology of TiO2. FTIR, UV-vis, and micro-Raman analyses showed the characteristic peaks of each material, indicating the impregnation of TAT in the nt-TiO2. Adhesives with nt-TiO2:TAT showed antimicrobial activity against biofilm formation compared to control (p < 0.05), without differences in the viability of planktonic bacteria (p > 0.05). All groups showed high percentages of pulp cell viability. The polymerization kinetics varied among groups, but all presented DC above 50%. The addition of 5 wt.% of nt-TiO2 and both groups containing nt-TiO2:TAT showed higher values of Knoop hardness compared to the control (p < 0.05). The groups with nt-TiO2:TAT presented lower Delta KHN% (p < 0.05) and higher UTS (p < 0.05) than the contro

关键词： Cellulose recycling   Acid catalysis   Cellulose hydrolysis   Superfine powder  

摘要： Consumer waste of cotton cellulose is receiving increasing attention. In this study, in order to recycle waste cotton cellulose fibre into ultrafine powder efficiently, a compact process containing sulfuric acid treatment and stone milling was examined. Scanning electronic microscopy (SEM) and atomic force microscope (AFM) were used to study the morphology of the original cellulose fibre, acid modified fibre and milled cellulose powder. The particle size, crystallinity and strength loss were also explored. The results illustrated that the fibre strength can be largely reduced by acid treatment and high temperature and the crystallinity of the fibre decreased after stone milling. Ultimately, the production efficiency and the output of the micron dry cellulose powder were greatly improved. About 1 kg dry ultrafine powder with particle size around 40 mu m was achieved in 1.5 h by stone milling in laboratory. This method shows a great potential for industrial application in the future. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Coffea arabica cv   heirloom   Coffee   Roasting   Physicochemical characteristics  

摘要： This study aimed to investigate the physicochemical characteristics of Ethiopian Coffea arabica cv. Heirloom coffee extracts with various roasting conditions. Green coffee beans were roasted at four different conditions (Light-medium, Medium, Moderately dark, and Very dark) and used to extract espresso and drip coffee. Moisture content in coffee beans was decreased as the roasting degree increased. The contents of crude fat and ash were lower in the Light-medium roasted coffee beans than in green coffee beans but increased as the roasting degree increased. The values of lightness (L*), redness (a*), yellowness (b*), and browning index of coffee extracts were decreased as the roasting degree increased. Total dissolved solids in espresso coffee were increased with increasing roasting degree but decreased in drip coffee. In both the extracts, the contents of reducing sugar, titratable acidity, organic acids, and chlorogenic acid were decreased, but that of caffeine was increased with the roasting degree increased.