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关键词： Amylopectin chain length   Double recessive sweet-waxy maize   Starch granule size   Viscosity  

摘要： Sweet-waxy is a new type of maize with waxy and sugary double recessive genes. This study aims to clarify starch structural and functional properties of this maize type. Grains with sweet-waxy and waxy phenotypes were separated from an ear using the two sweet-waxy maize hybrids of ATN and NKY as materials. Compared with waxy maize starch, the sweet-waxy maize starch mainly comprises small-sized round granules despite the typical waxy character of both starches. Mw, Mn, and relative crystallinity of sweet-waxy starch were higher than those of waxy starch in both hybrids. The average chain length of waxy starch was higher in ATN but lower in NKY compared with that of sweet-waxy starch. However, polydispersity (Mw/Mn) and F1 fraction were high in sweet-waxy and waxy starches in ATN and NKY, respectively. Breakdown viscosity, gelatinization enthalpy and temperatures of both hybrids were low in sweet-waxy starch. Peak viscosity was higher in waxy starch in NKY and similar between sweet-waxy and waxy starches in ATN. Retrogradation percentage was high and low for sweet-waxy starches in ATN and NKY, respectively. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Kaolinite   Dissolution kinetics   Mechanochemistry   Bayer process   Spent liquor   Desilication  

摘要： Using industrial spent Bayer-liquor solution and 95 ?C temperature, the dissolution and desilication products formation kinetics of five raw kaolinite samples obtained from different sources were found to display profound differences. It was hypothesized that these differences were connected to the physico-chemical properties of the solids. The solids were characterized by powder X-ray diffractometry, N2 adsorption-desorption isotherms, temperature-programmed NH3 desorption, infrared and ultraviolet?visible diffuse reflectance spectroscopies, scanning electron microscopy connected with energy dispersive X-ray analysis, dynamic light scattering and thermal analysis. The detailed structural study of the as-received samples was supplemented by exploring the effect of mechanochemical treatment. It was found that beside specific surface area and pore volume, the amount of the Lewis acid sites proved to be the most important factors, and the picture was found to be modulated by the degree of aggregation of the primary particles. On mechanochemical treatment (60 min milling in a mixer mill), the number of the acid sites increased significantly (from 0.004?0.013 to 0.055?0.066 mmol/g), and largely as a result of this, the dissolution of all raw kaolinites became practically instantaneous and source-independent.

关键词： Melanoidin (MLD)   Black garlic   Physicochemical properties   Antioxidant activities   Simulated digestion  

摘要： As the important compounds in black garlic, the physicochemical properties and bioactivities of melanoidin (MLD) were investigated in this study. The results showed that MLD possessed strong metal-ion chelating capacity and radical scavenging activities which were positively correlative with molecular weight (MW). During the simulated digestion in vitro, the ultraviolet absorption, browning degree and MW distribution of MLD remained the same as initial. It proved that the MLD from black garlic could be indigestible like the dietary fiber with little loss of volatile compounds and polysaccharides. Remarkably, the bioactivities of MLD were reduced significantly under the treatment of alpha-amylase or hydrochloric acid, while they were stable and retained over 60% after adding pepsin and pancreatin. This study provides fundamental evidences for further research and widely application of MLD and black garlic in the production of functional food or food additives.

关键词： LMP-peptide complexes   beta-carotene   Bioaccessibility   Camellia oil  

摘要： To improve the stabilities of low methoxy pectin (LMP) stabilized O/W emulsions for the delivery of bioactive substances, LMP was firstly modified with soy peptide (SP), corn peptide (CP) and whey protein peptide (WPP), respectively, by using dry-heat method, then the properties of LMP-peptide complexes stabilized O/W emulsions were characterized and the in vitro digestion of emulsions with beta-carotene was test to evaluate the potential applications. LMP-peptide complexes were formed by covalent bonds according to FT-IR spectroscopy. Compared to LMP stabilized emulsions, LMP-peptide complexes stabilized emulsions had smaller droplet sizes and higher stabilities in the changed pH value, temperature and ionic strength. Based on the results of in vitro digestion tests, LMP-SP and LMP-WPP obtained by incubating LMP with peptides at 60 degrees C for 12 h at the weight ratio of 4:1 were more suitable for the preparation of O/W emulsions to deliver camellia oil and beta-carotene.

关键词： Ketchup   Bioactive compounds   Texture   Color   Sensory  

摘要： The addition of strawberry pulp to ketchup sauces may be an alternative to attend the consumers' demand for innovative products with functional appeal. Sauces were made using different tomato/strawberry pulp ratios (100:0;75:25;50:50;25:75;0:100) and characterized for the physicochemical characteristics, bioactive compounds, antioxidant activity, and consumers' acceptance. The strawberry-enriched ketchup sauces presented higher phenolics, total flavonoids, antioxidant activity, and increased fluidity, and lower browning index, hue angle, chroma, pH, and Bostwick consistency. The antioxidant activities (ABTS and DPPH) were positively correlated with phenolics (r = 0.96 and 0.91) and flavonoids (r = 0.92 and 0.89) contents, respectively. The replacement of up to 50% tomato pulp by strawberry pulp did not change the acidity, flavor, and overall acceptance of the samples. The strawberry pulp has proven to be an effective alternative to increase the concentrations of bioactive compounds while reducing the amount of sugar used in traditional ketchup formulations.

关键词： Hydrogen production   Nickel catalyst   Reforming of natural gas   Liquid natural gas  

摘要： This work deals with Ni catalysts supported on both mono and binary oxide prepared by a conventional wet impregnation method. The catalytic properties of the material were investigated in oxy-steam reforming of methane (OSRM) process. The physicochemical properties of the catalysts were extensively studied using techniques such as Temperature Programmed Reduction (TPR-H-2), Temperature Programmed Desorption of Ammonia (TPD-NH3), Brunauer Emmett Teller Method (BET), X-ray Diffraction studies (XRD), Thermal Analysis coupled with Mass Spectrometry (TG-DTA-MS), Time of Flight Secondary Ion Mass Spectrometer (ToF-SIMS), X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscope with EDX detector (SEM-EDX). The catalytic activity results showed that the Ni/CeO2 center dot La2O3 (2:1) catalyst exhibited superior activity and high selectivity towards hydrogen formation in the studied process due to the high content of Ni species present on the catalyst surface. The low activity of the Ni catalysts supported on La2O3 or binary oxide with high content of lanthanum oxide is related to the strong interaction of NiO with support.

关键词： Zein   Carboxymethyl dextrin   Nanoparticles   Curcumin   Stability  

摘要： In this work, zein/carboxymethyl dextrin nanoparticles were successfully fabricated at different zein to carboxymethyl dextrin (CMD) mass ratios. Zein/CMD nanoparticles with the negative charge and the smallest size (212 nm) were formed when the mass ratio of zein to CMD was 2:1, exhibiting improved encapsulation efficiency of curcumin (85.5%). Electrostatic interactions, hydrogen bonding and hydrophobic interactions were main driven forces for nanoparticles formulation and curcumin encapsulation. Fourier transform infrared spectroscopy determined curcumin might be partially embedded in CMD during encapsulation. The spherical structures of zein/CMD nanoparticles and curcumin-loaded zein/CMD nanoparticles were observed by transmission electron microscopy. The photothermal stability and antioxidant activity of curcumin were significantly enhanced after be loaded in zein/CMD nanoparticles. Furthermore, encapsulation of curcumin in zein/CMD nanoparticles significantly delayed the release of curcumin in simulated gastrointestinal fluids. These results indicated that zein/CMD nanoparticles could be effective encapsulating materials for bioactive compounds in food industry.

关键词： Tea polyphenols   Grass carp   Flavour   Healthcare   Flesh quality   Collagen  

摘要： Tea polyphenols (TP) are functional feed additives (antioxidants) derived from tea. Research to date has not investigated the impacts of TP on flavour quality, healthcare components, and physicochemical parameters of fish flesh. This study aimed to investigate whether dietary TP in growing grass carp could provide high quality fish flesh. 540 fish (187.49 +/- 0.66 g) were fed six diets with different concentrations of TP (0, 40, 80, 120, 160 and 200 mg / kg) for 60 days to determine the effects of TP on flesh quality. The results demonstrated that appropriate dietary TP supplementation benefits growing grass carp in the following respects: (1) promoting performance of growth and nutritional value of fish, (2) enhancing flavour of flesh by increasing the levels of umami-taste free amino acids (glutamic acid and aspartic acid) (3) increasing healthcare components of flesh particularly eicosapentaenoic acid (EPA 20:5n-3) and docosahexaenoic acid (DHA 22:6n-3), (4) improving physicochemical properties (firmness,pH, water-holding capacity) of flesh. The present research explores, for the first time, the effects of TP on enhancing the collagen content, which is partly correlated with the upregulation of type I collagen synthesis genes Col1 alpha 1 and Col1 alpha 2, mediated through transforming growth factor-beta 1 (TGF-beta 1) by Smad pathway in fish muscle. Based on growth performance (percentage weight gain) and fish flesh quality indices (EPA, DHA, shear force, and pH), the appropriate dietary supplementation of TP in growing grass carp were assessed to be 103.01, 116.30, 106.60, 141.15 and 113.49 mg/kg, using quadratic regression analysis. In summary, TP is a promising feed additive to improve fish flesh quality.

关键词： Soybean roasting   Beany flavor   Lipoxygenase   Peroxidase   Volatile compounds   Electronic nose   HS-SPME-GC-MS  

摘要： We applied oven-roasting on soybean in order to investigate their physicochemical, sensory, and volatile profiles using electronic nose and HS-SPME-GC-MS. Results revealed a temperature dependent kinetic on the physicochemical index except fat content. Roasting at 200 degrees C for 20 min decreased the protein dispersibility index about 38%;while, lipoxygenase and peroxidase were entirely inactivated. The primary heat sensitive amino acids were methionine, arginine, and cysteine. Electronic nose showed certain capacity to discriminate varying roasted soybeans. Out of 41 volatile compounds identified in soybean headspace, 2,5-dimethylpyrazine showed the highest abundance of 411.18 mu g/Kg. Regression model suggested the association of hexanal and aliphatic alcohols with beany flavor, while pyrazines, heterocycles, and furanoids showed a positive correlation with roasted flavor. The selected flavor markers can be used to predict the development of flavor in roasted soybeans. Our study emphasized the effect of roasting level on nutritive value and flavor profiles of soybeans.

关键词： Cetylpyridinium salicylate   Amino acid and glycylglycine   Solute-solvent interaction   Thermodynamic parameters  

摘要： The pharmaceutically active form of an ionic liquid, cetylpyridinium salicylate ([CetPy][Sal]), was synthesized, and the intermolecular interactions of [CetPy][Sal] with amino acids (glycine, L-alanine, L-valine, and Lleucine) and glycylglycine (AAGG) in aqueous media were investigated by measuring the density, conductivity and UV-visible spectra at different temperatures. The measured density data was used to compute the apparent molar volume at infinite dilution, V-2(0), (phi), the hydration number, n(H), the transfer volume, Delta V-t(0), and the apparent molar expansibility at infinite dilution, E-empty set(0), of AAGG in aqueous [CetPy][Sal] solution. The measured electrical conductivity was used to calculate the critical micelle concentration, cmc, and the relative thermodynamic quantities for the micellization of [CetPy][Sal] in an AAGG solution, i.e. the changes in the Gibbs free energy, the enthalpy, and the entropy. The binding constants between [CetPy][Sal] and AAGG were derived from UV-vis spectroscopic data. The aforementioned properties were analyzed in terms of the molecular interactions and structural changes existing in the studied ternary solutions of (AAGG +[CetPy][Sal]+water). (C) 2020 Elsevier B.V. All rights reserved.