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关键词： Optical and Electronic Materials   Characterization and Evaluation of Materials  

摘要： In the present study, pristine and Cd2+ modified SnO2 compositions [Sn(1-y)CdyO2, where y = 0, 0.05, and 0.10] were synthesized by co-precipitation technique. Structural studies were carried out by X-ray diffraction (XRD) analysis which revealed that all the compositions exhibited tetragonal rutile-type crystal structure with P4(2/)mnm space group with high purity (absence of secondary phases). FTIR spectra confirmed the formation of pristine and Cd2+ modified SnO2 nanocrystals as bend at 560 cm(-1) attributed to Sn-O-Sn stretching vibrations. UV-Vis optical spectra displayed a sharp peak at similar to 304 nm and similar to 311 nm belonging to UV region (200-400 nm) and a small hump at 561 nm corresponding to the visible region for Cd2+-doped compositions. FESEM micrographs depicted the nano-scale formation of pristine and Cd2+ modified SnO2 nanocrystals calcined at 600 degrees C and showed that grain size increased from 45.66 +/- 1.2 nm to 60.27 +/- 2.7 nm with increasing Cd2+ concentrations. HRTEM images confirmed the tetragonal crystallinity of as-synthesized nanocrystals as fringes attributed to (110) plane orientation with d-spacing similar to 0.34 nm exactly matched with XRD studies. Dielectric analysis showed that dielectric constant decreased with increasing Cd2+ in the compositions and I-V curves illustrated linear or ohmic behavior with diminishing values of resistances for higher Cd2+ concentrations.

关键词： Additional water   Ionothermal synthesis   Vanadium phosphate   Physicochemical properties  

摘要： In order to explore the effect of amount of additional water on physicochemical properties of vanadium phosphate (VPO) materials prepared in a Deep Eutectic Mixture (DES), various supernumerary amount of water (H2O: DES = 0, 0.13, 0.26, 0.39, 0.52, mass ratio) was added during synthesis. The result showed that adding appropriate quantity of water in preparation process was benefit to forming pore space framework and obtaining higher BET surface area, however, excessive quantities of water would destroy aperturestructure, seriously resulting in atresia. In addition, as the accessorial water content in a DES augmented, crystallite size of VPO materials increased and phase of that changed from amorphous to crystalline state. More than that crystalline phase types also altered. Further, the morphology of products varied from amorphous blocks to nano-particles and then to nano-sheets, finally to cuboids. What's more, VPO catalysts corresponded to reaction conversions were pretty much the same, but reaction selectivity existed a great difference under the same reaction condition. It was obvious that water played an important role in ionothermal synthesis, which may inspire us to regulate the morphology, pore space framework, crystallite size and catalytic performance of VPO materials by controlling moisture content of DES in the future.

关键词： Food technology  

摘要： 1. Introduction 2 2. Historical aspects 2 3. Manufacturing procedures 2 3.1. Cream cheese making 1870-1920 2 3.2. Cream cheese making 1920-1945 3 3.2.1. The Dahlberg process3 3.2.2. The Marquardt process 3 3.2.3. Roundy and Price process4 3.2.4. Reichert and Crowe process4 3.3. Cream cheese making 1945-1980 4 3.3.1. The Oscar Link process 4 3.3.2. The Berge process 4 3.3.3. Carswell and Hurlburt process 5 3.4. Membrane processing since 1980 5 3.4.1. Ultrafiltration 5 3.4.2. Nanofiltration + ultrafiltration 5 3.4.3. Microfiltration 5 Cream cheese is an acid coagulated particle microgel with a structure consisting of protein-covered milk fat globules, forming aggregated clusters at different scales, with pores filled with whey and characterised by its creamy taste and spread-ability. This review focuses on the technology for the production of high fat cream cheese, its historical background and evolution from 1870 until today, covering the different processing developments and breakthroughs. In addition, fundamental physico-chemical aspects arising from technological and processing steps, that influence cream cheese properties, are discussed.

关键词： Pomegranate   Growth pattern   Geometrical properties   Gravimetrical properties   Chemical properties  

摘要： Pomegranate acceptability by consumers and processors depends on basically on a combination of several quality attributes such as shape and size (geometrical properties), fruit mass and aril yield (gravimetrical properties), rind and aril color, sugar content, acidity and flavour. This study was conducted to investigate the physical properties (geometrical and gravimetrical properties) and some chemical properties pomegranate fruit and their arils as well as aril colour attributes at four distinct maturity stages between 88 and 143 days after full bloom (DAFB). Chemical properties such as pH, total soluble solids (TSS), titratable acidity (TA), dry weight content (DW) of fruit and aril were studied. Significant (P < 0.05) increase in geometrical properties (except sphericity), some gravimetrical properties (fruit mass, true volume of fruit and aril, arils mass in fruit and bulk density of aril), total soluble solids (TSS), pH and dry weight content of fruit, coupled with significant (P < 0.05) decline in true density of fruit and aril, aril porosity and titratable acidity (TA) as well as dry weight content of aril was observed along the days after full bloom (DAFB). The results also showed that differences at a 5% level of significance were found among the developmental stages in the colour of arils. Furthermore, pearson correlation was used to investigate the relationship between selected attribute associated fruit maturity of the pomegranate cultivar. Interesting significantly strong correlations were observed.

关键词： Porosity  

摘要： The process of bone regeneration in bone grafting procedures is greatly influenced by the physicochemical properties of the bone graft substitute. In this study, porous phosphate glass (PPG) morsels were developed and their physicochemical properties such as degradation, crystallinity, organic content, surface topography, particle size and porosity were evaluated using various analytical methods. The in vitro cytotoxicity of the PPG morsels was assessed and the interaction of the PPG morsels with Dental Pulp Stem Cells (DPSCs) was studied by measuring cell proliferation and cell penetration depth. The cell-material interactions between PPG morsels and a commercially available xenograft (XG) were compared. The PPG morsels were observed to be amorphous, biocompatible and highly porous (porosity = 58.45%). From in vitro experiments, PPG morsels were observed to be non-cytotoxic and showed better cell proliferation. The internal surface of PPG was easily accessible to the cells compared to XG. [GRAPHICS] .

关键词： Clove bud   Antioxidant   Antimicrobial   Color   Cake   Microwave   Roasted  

摘要： This study evaluated the physico-chemical, antimicrobial, and organoleptic properties of roasted clove bud in cake preservation during 28 days of storage at room temperature (30 degrees C) and compared with cake containing synthetic antioxidant. The results showed that the clove as such and in roasted form was able to retard the oxidative products in cakes when compared with synthetic antioxidant. Clove as such and in roasted form was more effective as antimicrobial agent as evident from the growth of the tested microorganisms. The cake containing unroasted and roasted clove bud powder showed more antioxidant properties compared with cake containing synthetic antioxidant. The pattern of chemical composition of clove bud oil as such and roasted by hot plate and microwave was responsible for more stability of cake when compared with cake containing synthetic antioxidant. Also, sensory results indicated in general the acceptability of the different cake samples. Color was observed to be more intense in case of roasted samples. Roasted samples indicated more hardness due to change in morphology by heating. Clove bud with intact essential oil as such and its roasted form could be used as a natural antioxidant and antimicrobial agent in foodstuffs, particularly those containing lipid and can help to extend the shelf life of those food products, besides their health safety.

关键词： Blueberry wine   Deacidification   Fermentation   Non-saccharomyces   Organic acid  

摘要： Blueberry wine has an excessively sour taste due to the presence of high-level of organic acids. Pichia fermentans JT-1-3 with a strong ability to degrade citric acid was selected for blueberry wine production in this work. The flocculation of JT-1-3 in comparison with two S. cerevisiaes strains was evaluated. Then citric acid degradation of JT-1-3 was assessed in synthetic media with different citric acid/glucose ratios under shaking or static conditions. Finally, JT-1-3 was inoculated in blueberry juice for fermentation. The results confirmed that JT-1-3 had appropriate flocculation and consumed citric acid and glucose greatly. In final wines, 6.25% (v/v) alcohol was achieved with 1.83% (w/w) residual sugar. Compared with juice, citric, malic and tartaric acids declined significantly by 43.35%, 35.29% and 44.68% in wine, respectively. 2-phenylethanol, ethyl 9-hexadecenoate, ethyl decanoate were the main volatiles in blueberry wine and most esters contributed to the aroma with high odor activity values. Sensory evaluation showed that wine produced by JT-1-3 imparted improved taste with lower acidity, bitterness and hotness perceptions compared with S. cerevisiae fermentation. This work revealed that JT-1-3 had a great potential to be applied for blueberry wine fermentation along with deacidification.

关键词： color   isomaltulose   muffins   oligofructose   sensory properties   sweeteners   texture  

摘要： This article analyses, the replacement of sucrose in muffins with nine different combinations of isomaltulose and oligofructose. Being a structural isomer of sucrose with approx. 50% of sucrose sweetness, isomaltulose is non-cariogenic and with a low glycemic profile but having the same calories as sucrose. Oligofructose is composed of fructose polymers, with a reduced caloric value and prebiotic effect. Specifically, height, percentage of alveoli, water content, A(w), mechanical, and optical properties have been measured along with a sensory evaluation. The results showed that all combinations of sweeteners gave place to softer muffins than control ones. Moreover, isomaltulose caused a darkening of the products likely due to an enhancement of the Maillard reactions. The highest amount of isomaltulose and the absence of sucrose meant the worst score in sweetness and flavor due to the low sweetening powder of isomaltulose.

关键词： Germination   ATR-FTIR   Starch digestion   Cereal grains  

摘要： The cereal grains such as wheat, barley, sorghum, millets were evaluated before and after germination (24 h, 48 h and 72 h) and compared for their proximate composition, antioxidant activity, total phenolic content, total flavonoid content, pasting properties, in vitro starch digestibility and FTIR spectroscopy. Germination inversely affected the protein, fat, and ash content of different cereal grains. The germinated flours have less water content and higher oil absorption capacities along with reduced starch content. The contents of rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) in the ungerminated cereal flours ranged from 20.7 to 32.1%, 26.9 to 38.0% and 6.2 to 17.6% respectively but after germination of 72 h, the RDS content increased from 26.5 to 36.2% while SDS and RS content decreased from 26.1% (sorghum) to 16% (barley) and 14.7% (barley) to 4.6% (wheat) respectively. The drought-tolerant crops (sorghum, millets and barley) are potential sources of antioxidants and phenolic content and yielded lower hydrolysis index and estimated glycaemic index upon germination. The highest section of antiparallal beta-sheet, alpha-helix and beta-turns were found in wheat flour followed by sorghum flour and their proportion decreased with continuous germination. The continuous reduction of viscosity was evaluated with the progress in germination. Overall, germination is a way to get health-promoting compounds from less utilizing cereal such as millets, sorghum and barley and enhance their uses to nourish the huge population with the aim to fulfill their nutritional requirements.

关键词： Antioxidant hydrocolloid   Althaea officinalis L   Response surface methodology   Total phenolic content   Flavonoids content  

摘要： In this study, the effect of root powder to water (RP/W) ratio (0.05, 0.10, and 0.15% w/v), temperature (30, 60, and 90 degrees C) and pH (3, 7, and 11) were investigated by response surface methodology to extract mucilage. The optimized conditions of mucilage extraction were the RP/W ratio (0.104% w/v), temperature 50.54 degrees C, and pH 3.00. The maximum content of protein, carbohydrate, and fat achieved at a temperature of 30 degrees C. The maximum content of dry mucilage, total phenolic and antioxidant activity obtained at a temperature of 90 degrees C while it was at a temperature of 60 degrees C for total flavonoids contents. The maximum protein, carbohydrate, fat, total phenolic contents and antioxidant activity was obtained at pH 3. The maximum content of dry mucilage was achieved at pH 11. The rise in the Hollyhock's RP/W ratio caused an increase in the content of total phenolic, total flavonoids, and protein content of extracted mucilage, but the reduction in fat and carbohydrate contents. Differential scanning calorimetry proves that the heat profile of the sample is endothermic. Thermal gravimetric analysis indicated that a decrease of the sample's weight to the amount of 70.22%, occurred in the temperature range of 480.96 degrees C to 536.37 degrees C. The Fourier transform infrared spectroscopy spectrum confirmed the existence of carboxyl groups in polysaccharide of Hollyhock's root mucilage. The results of this study approved that mucilage of Hollyhock's root is a natural antioxidant compound and has the potential for utilization in the food and drug industry as a new ingredient.