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关键词： Red radish roots   Nanopowder   UF-Soft cheese   Antioxidant activities   Sensory properties  

摘要： The present study highlights an innovative product of ultrafiltration cheese (UF-soft cheese) containing red radish roots in nanopowder form for providing a healthy source of nutrients for the human body. Red radish roots nanopowder used at the levels of (1, 2, and 3%) in the manufacturing of UF-soft cheeses. The chemical properties of the red radish roots nanopowder and its particle size distribution were analyzed. Furthermore, chemical, rheological, colors, antioxidants, and sensory properties were investigated in the cheese during cold storage for one month. The results showed that red radish roots powder followed a nanosize form with an average diameter of 71.8 nm and 0.533 polydispersity indexes (PDI). Moreover, it possessed excellent quantities of protein, ash, fiber, and antioxidants activities. Additionally, texture profile measurements, chemical properties, and sensory scores of cheese were improved by increasing the supplementation of red radish roots nanopowder than control cheese during their storage period. Hence, the addition of red radish roots in nanopowder as a natural ingredient to enhance the quality of cheese products as well as increase its nutritional value.

关键词： Azadirachta indica wood   Carbonization   Activated carbon pellets   Physicochemical activation   Biomethane adsorption   Energy storage  

摘要： Adsorbed natural gas technology has offered various advantages over the normal compression and liquefaction based energy storage. Activated carbons are the materials that have micro-porous structures as required for methane adsorption. Herein, we highlight the preparation of activated carbons using KOH and steam in combined form. The combined activated carbons have a surface area of 963 m2/g as compared to chemically activated of 764 m2/g. For the analysis of biomethane adsorption, we also report the preparation of pellets using bentonite and Kaolin. The best results obtained were found with 20 % (weight basis) of Kaolin with gravimetric methane uptake of 0.28 g/g and volumetric methane uptake of 231 v/v with 177 v/v of deliverable capacity during the desorption from storage cylinder.

关键词： Textures  

摘要： The aim of this study was to evaluate the effects of quinoa flour (QF) addition at different levels (0%, 1.0%, 2.0%, and 3.0%) on the physicochemical, syneresis, antioxidant activity, textural and sensorial characteristics of UF-soft cheeses during refrigerated storage for 30 days. QF-added samples exhibited significantly (p <= .001) higher level of protein, fat, ash, dietary fiber, total phenolic, and antioxidant activity with lower syneresis than the control cheese. Magnesium, phosphorus, iron, and zinc were higher in the QF-added samples than in control. The syneresis was significantly lower (p <= .001) in QF-added samples than in control. The texture profile analysis showed that QF-added samples were less soft, more gummy, chewy, and springy than control cheese. Sensory evaluation of cheeses supplemented with 1% or 2% QF had the highest score of overall acceptability since the addition of 3%QF had undesirable effects on consumer acceptability. Practical applications The addition of 1% or 2% quinoa flour to UF-soft cheese is an option to improve the content of nutritionally important compounds of the product.

关键词： Physicochemical properties  

摘要： The impact of melon juice clarification through two conventional pretreatments on the physicochemical properties of an alcoholic beverage was studied. Fresh melon juice (FJ), filtered fresh juice (FFJ) through a sieve mesh, and cold sedimented filtered fresh juice (SFFJ) were used, with which the liqueurs were made and macerated for 5 days. The degrees Brix in the FJ was 8.16, which decreased to 3 degrees Brix in the last pretreatment. There was a reduction of the total solids content in the SFFJ from 11.09% to 2.46%. The viscosity increased as the shear rate increased at the three different temperatures evaluated, the greatest trend in viscosity increase occurred at 25 degrees C. The results show how these two conventional clarification processes influence the removal of suspended solids in melon juice and how they can be useful in the preparation of an alcoholic beverage with a low amount of solids. Practical applications This study has industrial implications in the production of melon juice through two conventional pretreatments in the elaboration of an alcoholic beverage. The results show how these two conventional clarification processes influence the removal of suspended solids in melon juice and how they can be useful in preparing a low solids alcoholic beverage.

关键词： Alkaline extraction   in vitro digestibility   physicochemical properties   Taro flour   taro starch  

摘要： This research aimed to study physicochemical properties and in vitro digestibility of flours and starches from taro cultivated in different regions of Thailand, that is, Kanchanaburi (KB), Chiang Mai (CM), Phetchaburi (PB) and Saraburi (SB). Taro starches were extracted from taro flours using either water or alkaline extraction. The taro flours had significantly (P <= 0.05) larger particle size, higher pasting and gelatinisation temperatures, and resistant starch content but lower total starch content, whiteness (L* value), paste viscosities and clarity than their corresponding extracted starches. All the taro starches exhibited polygonal and irregular granules and gave A-type X-ray diffraction pattern. The alkaline-extracted taro starches had significantly (P <= 0.05) higher extraction yield, total starch content, L* value, pasting and gelatinisation temperatures, and paste clarity but lower granular size, amylose content, resistant starch content, paste viscosities and relative crystallinity than their water-extracted counterparts.

关键词： high-chromium steel   oxygen ion implantation   corrosion   chemical composition and structure of surface layers  

摘要： The effect of oxygen ion implantation on the physicochemical structure of the surface and the corrosion-electrochemical behavior of high-chromium Fe13Cr steel has been examined by potentiometry, atomic force microscopy, X-ray photoelectron spectroscopy, and microhardness measurements. Ion implantation leads to a significant reduction in corrosion losses. Optimal from the point of surface passivation and, consequently, reduction of corrosion losses of the material is the regime of steel treatment with oxygen ions with a dose of D = 5 x 10(16) cm(-2), after which the sample demonstrates the most stable behavior during local and general corrosion. It has been shown that the increase in the corrosion resistance of steel is due to the redistribution of elements in the surface layers caused by ion implantation and the intense formation of spinels of variable composition consisting of iron and chromium oxides with different oxidation states. In this case, the microhardness of the surface layers of the steel after ion implantation does not change significantly.

关键词： Silk sericin   Di-aldehyde bacterial nanocellulose   Crosslinking   Water resistance  

摘要： The manufacture of eco-friendly cocoon silk-derived sericin films increases the availability of sericulture resources and the interest in expanding the range of the potential applications of sericin-based materials. However, the brittleness and weak tensile properties of sericin and its vulnerability to moist environments have limited its use. To overcome these two shortcomings of sericin, a functionalized bacterial cellulose-derived nanocrystal (average diameter: 25.4 nm) capable of physical strengthening and chemical crosslinking on existing sericin films was prepared. The improvement of the optical, physicochemical, and mechanical properties of the sericin film was observed through the dialdehyde bacterial cellulose nanocrystals (D-CNCs) incorporated into the silk sericin (SS) matrix. The physical reinforcing effect of the D-CNCs on the SS films enhances the mechanical properties of the films. Simultaneously, the chemical crosslinking reaction of D-CNCs develops the ultraviolet-blocking, water-resistant, and antioxidant properties of the films. The simultaneous fabrication, physical reinforcement, and chemical crosslinking of the SS/D-CNCs biocomposite film produced using an aqueous solution will provide information on the functionalization and performance improvement of water-soluble biopolymeric materials, especially hydrophilic protein resources.

关键词： ZnO nanoparticles   Fe dopant   XPS   TGA   Antibacterial activity   72   80   Le   81   07   Pr   81   16   Dn   78   67   Sc  

摘要： Undoped and Fe-doped ZnO nanoparticles were synthesized by the sol-gel method, and the related physicochemical properties were characterized by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy (SEM). Annealing of the nanoparticles at 400 and 500 degrees C was studied. The prepared nanoparticles showed the hexagonal phase of wurtzite structure, and the grain size was in the range of 30-47 nm. Fe ions were in oxidation state of + 3 as was revealed by XPS analysis of the 0.7 at% Fe-doped powder. The photocatalytic properties of ZnO:Fe nanoparticles were investigated by inactivation ofPseudomonas aeruginosaunder UV-B lamp irradiation. Optical density, colony counting method and SEM were used to survey the antibacterial activity of the nanoparticles. After analyzing the results, it was found that the prepared nanoparticles have a very effective antimicrobial activity againstP. aeruginosa. This activity increases by increasing/decreasing the amount of Fe in the compound/annealing temperature. Heavily doped ZnO nanoparticles showed a considerable antibacterial effect againstP. aeruginosa.

关键词： microstructure   pasting   predicted glycemic index   resistant starch   rice starch  

摘要： Four rice cultivars (SR-4, K-39, Mushq Budij, and Pigmented) grown in Kashmir were selected for starch extraction and characterization. Rice starches were observed for physicochemical, functional properties, and in vitro digestibility studies for estimation of their glycemic indices. Compositional analysis revealed that moisture, crude fat, ash, and protein contents of rice starches varied significantly (p <= 0.05) from 7.96 to 11.33, 0.15-0.31, 0.23-0.27, and 0.29-0.36 g per 100 g. Pigmented starch revealed high amylose content (25.40 g per 100g) that contribute for high solubility index (0.01-0.08 g per g) and low peak viscosity (3.31 Pa s). Scanning electron microscopy of all the starches revealed polyhedral granule shape. An X-ray diffractogram showed the starches to possess A-type pattern with prominent peaks at 15.27, 17.63, and 23.29 degrees. Gelatinization enthalpy of starches varied significantly (p <= 0.05) from 8.30 to 11.15 J g(-1). K-39 starch with least amylose content (21.08 g per 100 g) had high peak (92.01 degrees C) and conclusion (107.95 degrees C) temperatures, indicating more thermal stability. Pigmented starch displayed high resistant starch content (12.61 g per 100 g). Starches displayed high predicted glycemic index scores (82.10-84.80), indicating their non-utility for diabetic populations.

关键词： Washing pretreatment   Co-pyrolysis   Synergistic effect   Physicochemical property evolution   Modified biochar  

摘要： In this study, walnut shell was washed by deionized water, acetic acid and hydrochloric acid, followed by preparation of advanced biochar via co-pyrolysis with bio-oil distillation residue. The influence of washing pretreatment on feedstock was determined by thermogravimetric analyzer, Fourier transform infrared spectroscopy and X-ray diffraction, meanwhile, the physicochemical property evolution of biochar was characterized by Elemental analyzer and Raman spectroscopy. The results indicated washing pretreatment would change the distribution of components, decrease ash content and further strengthen the ordered arrangement of microcrystals. Moreover, washing pretreatment had a negative effect on biochar yield, yet co-pyrolysis of bio-oil distillation residue and washed walnut shell would enhance the relative increase rate of biochar yield and optimize the elemental distribution (i.e. increased carbon content). In addition, biochar yielded from washed walnut shell exhibited a relatively ordered carbon structure, whereas co-pyrolysis would significantly disrupt the arrangement of microcrystals. More importantly, hydrochloric acid washing and co-pyrolysis both had a positive effect on enhanced thermal stability and increased carbon purity of biochar.