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关键词： Molecular weight distribution  

摘要： The physicochemical, scavenging, and proliferative properties of gelatin from Yak skin that was affected by an extraction and drying method were investigated. The yield of freeze-dried enzymatic hydrolyzed gelatin (FEG) was the lowest, which had a lower oil binding capacity, water-holding capacity, metal chelating activity (p < .05), regular molecular weight distribution, and a clearly superior ability to promote lymphatic proliferation in mice than heat-concentrated heat-extracted gelatin (HCG), freeze-dried heat-extracted gelatin (FDG), and spray-dried heat-extracted gelatin (SDG). HCG has compactness and no obvious pore structure, while SDG has obvious particle structure. The results showed that heat is a key factor, which could influence the physicochemical and functional properties of gelatin. Freeze-dried enzymatic hydrolyzed gelatin is a reasonable preparation method to obtain the gelatin that with higher biological activity. Practical applications In recent years, handling of animal discards is demanded for the underutilization of animal resources. This study aimed to compare the properties of Yak skin gelatin with different prepared methods, and provide a scientific basis for the preparation of Yak skin gelatin. With these physicochemical and biological functions, Yak skin gelatin could be a potential ingredient used in food, pharmaceuticals, and cosmetics with different preparation.

关键词： LTSB   X-Ray diffraction   FTIR   Optical band gap   Antibacterial activity  

摘要： Highly translucent nonlinear single crystals of L-Threoninum Sodium Bromide (LTSB) has been grown because of their rising need for everyday life and the XRD studies (PXRD and SXRD) solemnly affirmed the crystallinity and non-centrosymmetric space group of LTSB materials. The bonding nature and diverse functional groups in LTSB were demonstrated by FTIR analysis when they absorb infrared radiation. The optical behavior of LTSB crystals was explored through UV-Vis spectroscopy, which shows optical parameters depend on photon energy with band gap E-g = 5.7 eV which was suitable for optoelectronic devices. The electrical properties of LTSB crystals were measured by using dielectric measurement. The solid state parameters of LTSB crystal were calculated. An antibacterial activity developed by LTSB crystals against different pathogenic bacteria were examined using the Agar disk diffusion process. The antibacterial inhibitory activity of LTSB crystal revealed that it can be used to treat a variety of bacterial infections. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

关键词： Electrophoresis   Cooking   Protein change   Hard-to-cook  

摘要： Beans (Phaseolus vulgaris L.) contain nutritional and functional compounds, and form a staple diet for approximately one-third of the population worldwide. Due to the seasonal production of beans, the grains need to be stored for the off-season, and, in general, quality losses are observed. Among the main property changes, changes in color and cooking properties are easily perceived. Therefore, the storage conditions that prevent (low temperature and vacuum) and that favor (room temperature and absence of vacuum) the occurrence of these changes was studied to better understand the possible causative modifications and alterations in the proteomic profile of beans. The best storage condition involved the combination of low temperatures with vacuum;however, with one year of storage at this condition, a loss of quality with respect to coloration, cooking property and protein profile was observed.

关键词： Faba bean   Tannin   Heat processing   Molecular structure  

摘要： This study aimed to determine the heat processing impact on the protein molecular structure (amide I, amide II, alpha-helix, and beta-sheet), and the nutritional characteristics (nutrient profiles, rumen degradation, intestinal digestion, and true protein supply) of faba bean grown in western Canada. Low tannin (LT) and normal tannin (NT) faba bean varieties were used for the present study, where varieties (n = 3) for each tannin level were used as a replicate. Based on previously published studies, sample groups were either heated with steam pressure at 121 degrees C for 30 minute (min) using a medium steam sterilizer or with microwave irradiation for 3 min in a conventional microwave with a power of 900 W and irradiation frequency of 2450 MHz. All seed was ground using a roller mill before heating. Heat-induced molecular structure changes were determined with Fourier Transformed Infrared spectroscopy (FTIR) while nutrient profiles, including dry matter (DM), crude protein (CP), soluble crude protein (SCP), and starch were obtained with traditional chemical analyses. An in situ rumen degradation study and a modified three-step in vitro technique was performed to analyze the degradation parameters and intestinal digestibility of feed nutrients in faba bean. Results showed that the peak area ratio of amide Ito amide II was lower in normal tannin faba bean types (1.835 vs. 2.073 absorbance units (AU), P < 0.0001) compared to low tannin faba bean types with both heat treatments, while the peak height ratio of alpha-helix to beta-sheet was higher in normal tannin types (1.249 vs. 1.090 AU, P < 0.0001) relative to low tannin types. Additionally, steam pressure reduced the SCP (45 vs. avg. 188 g/kg DM, P < 0.01), and increased the intestinal digestibility of crude protein (dIDP, 0.89 vs. avg. 0.79, P = 0.03) compared to other treatments. The truly absorbed protein supply in the small intestine was higher with steam pressure (DVE, 180 vs. 130 and 117 g/kg DM, P < 0.01) rel

关键词： Rice cultivars   Physicochemical   Functional   Thermal   Cooking   Properties  

摘要： Physicochemical, functional, thermal, pasting and cooking properties of five Indian rice cultivars, ADT 36, 43, 39, IW PONNI and CR1009 were investigated. The starch, protein and fat contents varied from 1.321 to 2.489 mg/ml, 11.16-13.32% and 1.19-1.77% respectively, showing significant difference amongst the cultivars. ADT46 showed the highest amylose-amylopectin ratio. Water (103.55-132.48%) and oil (112.89-137.30%) absorption capacities also varied significantly. CR1009 showed highest swelling power at 60 degrees C, whereas IW PONNI exhibited the highest solubility (10.165%). The gel consistency of rice flours extended from 1.32 to 4.12 cm. The thermal properties of rice cultivars were found to be profoundly affected by amylopectin and showed correlation with amylose-amylopectin ratio. The pasting properties of rice flours also varied significantly, with peak viscosity and breakdown viscosity ranging between 2068.5-839 Cp and 1609.5-764.15 Cp respectively. The cooking time of the rice grains was found to be consistent with their shape and size. ADT43 and ADT46 showed the highest and least water uptake % on cooking. ADT46 showed the least cooking loss %, owing to the highest pasting viscosity. This study delivers the knowledge of the Indian rice cultivars, to be used for utilization of rice varieties for different products with relevance to the properties and enhance the post-harvest value chain improvement.

关键词： alginate   emulsion method   functional food   microalgae   non-fat stirred yogurt   sensory evaluation   WPC  

摘要： BACKGROUND Consumption ofSpirulina-based functionalized food is usually unpleasant due to its specific sensorial properties. Therefore,Spirulinawas encapsulated using alginate and whey protein concentrate (WPC) by emulsification method, and the effect of adding free and microencapsulatedSpirulina(MS) to non-fat stirred yogurt was investigated during storage. RESULTS Scanning electron microscope investigated microcapsules morphology and their mean particle size that was 52 mu m, and electrostatic interaction between wall materials was illustrated by Fourier- transform infrared spectroscopy. The microspheres had appropriate encapsulation efficiency (44.54 +/- 0.06%). Complete release ofSpirulinafrom the microcapsules was observed in simulated intestinal fluid, which is favorable forLactobacillusgrowth in human intestinal tract. Encapsulation caused meaningful differences in colorimetric factors, markedly inL*. Moreover, free and MS were added to yogurt samples, and the results showed that the physicochemical properties (pH, color, viscosity, water holding capacity and susceptibility to syneresis) and sensorial assessment of MS yogurt were positively affected. During the storage, MS yogurt had higher pH value than the others;furthermore, it showed the lowest syneresis and a constant increase in viscosity. Finally, the sensory evaluation results of MS yogurt, in comparison with the free form ofSpirulinautilization, indicated improved acceptance of the produced functional food. CONCLUSION Results showed an obvious impact of encapsulation on the physicochemical properties of yogurt containing MS. The sensory evaluation showed that encapsulation could generally enhance the customer's satisfaction. It can be stated that masking microalgae color and flavor by microencapsulation could be used for dairy products fortification by microalgae. (c) 2020 Society of Chemical Industry

关键词： isolation   pearling   physical properties   sorghum   starch  

摘要： The aim of this study is to optimize starch isolation from different sorghum cultivars and characterize the starch from fourteen red and white sorghum hybrids. Methods involving sulfite maceration and/or protein hydrolysis are assayed. Recovery and yield, residual protein, total and starch damage, whiteness index (WI), water absorption, solubility, and swelling power of isolated starches are compared in order to select the appropriate isolation method. Results indicate that starch recoveries between 44-76%. Isolated starches present 0.58-2.4 g 100 g(-1)residual proteins, 89.1-90.6 WI, 5.10-9.57 g 100 g(-1)solubility, and 15.09-22.57 g water 100 g(-1)swelling power. Taking into account recovery, residual protein, WI, and good hydration properties of starch, the maceration during 24 h combined with protein hydrolysis during 3 h is used to isolate starches. After starch isolation, its characterization (residual protein, total and damage starch, amylose content, particle size distribution, WI, crystallinity, gelatinization temperature, water absorption, solubility, and swelling power) is performed. Principal component analysis shows that color as indicator of variety is influenced by the structure, composition, and physicochemical properties of isolated starch. Starches from white sorghum hybrids have higher amylose content and gelatinization temperature than the red ones, which affect starch solubility, and swelling power.

关键词： Chitosan   kappa-Carrageenan   Atomic force microscopy   Layer-by-layer assembly   In Vitro cytotoxicity assay  

摘要： Thin films based on the natural polysaccharides kappa-carrageenan (Carr) and chitosan (Chit) were formed by layer-by-layer deposition technique. Surface topography and mechanical characteristics (Young's modulus, adhesion strength) of the polymer films with different number of layers were determined using various modes of atomic force microscopy (AFM). Polymer films were used to deposit on the surface of nitinol (NiTi) plates. The creation of polysaccharide coatings on nitinol led to a change in surface properties, such as hydrophilicity and root mean square roughness. in vitro cytotoxicity assay for nitinol plates with and without polymer coating by the MG-63 osteoblast-like cell line was conducted and was shown that all the studied samples are not toxic. A decrease in cytotoxicity for samples with a polymer film consisting of 4 layers of chitosan and carrageenan was shown as compared to an uncoated nitinol plates.

关键词： Gluten-free   Natural fermentation   Rice starch   Rice protein   Pasting properties   Texture properties  

摘要： This study examined the effects of natural fermentation on rice components to understand how fermentation affects the physicochemical and functional properties of rice flour. We found that natural fermentation for 72 h had almost no effect on the structural properties of rice starch and slightly affected the protein content and composition. The charged amino acid content of rice flour decreased after fermentation, while the surface hydrophobicity increased. The surface charge of rice flour increased from -12.7 mV before fermentation to +7.06 mV after 72 h of fermentation. The reduced protein content in fermented rice flour increased the gelatinization enthalpy of rice flour to a level similar to that of starch, and enhanced starch granule expansion, resulting in an increased peak viscosity and granule breakdown, but decreased final viscosity, setback, and pasting temperature. Differences in the protein composition, surface hydrophobicity, and surface charge between fermented and non-fermented rice flour explained the greater hardness of fermented rice flour. We conclude that natural fermentation can improve the functional properties of rice flour through protein modification on the starch granule surface.

关键词： Whole wheat   Asian noodles   Sensory   Texture  

摘要： Whole wheat products have gained popularity in recent years due to the health and nutritional benefits, with Asian salted noodles as one formulation. However, there is a general perception of decreased product quality and sensory acceptance of whole wheat noodles This study examined changes to sensory properties, texture (tensile and compressive strength), color, and cooking loss of noodles prepared from blends of wheat flour and bran that underwent five forms of hydro, thermal, pressure and their combined treatments: autoclaving, extrusion, jet cooking, puffing, and roasting. Including the control (bran without processing) all six treatments were deemed palatable by sensory panel evaluation despite having statistically significant differences in physiochemical and sensory properties. For instance, 10 of the 22 sensory properties demonstrated significant differences among treatments. Bran processing tended to result in weaker (tensile and compressive strength) and stickier noodles while allowing for greater uptake of water during cooking.