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关键词： Trehalose   Maltodextrin   Stevioside   Dark compound chocolate   Viscosity  

摘要： The sucrose-free dark chocolate development is receiving attention due to increasing market demand for foods with reduced sugar. This study aimed to determine the physical and sensory properties, and the storage stability of sucrose-free dark compound chocolate by replacing the sucrose with inulin, Fructo-oligosaccharides (FOS), trehalose, or maltodextrin (M10 and M30) on a volume basis along with stevioside as a sweetening agent. Melting and crystallization properties, particle size, moisture content, rheological behaviour, hardness, bloom formation and sensory evaluation were examined using differential scanning calorimetry, particle size analyser, rheometer, and texture analysis, respectively. Sucrose substitution had no significant impact on the melting and crystallization behaviour in a compound chocolate model system. However, all sucrose-free dark compound chocolate displayed lower Casson viscosity, yield value and hardness than sucrose-containing dark compound chocolate, which may because the weaker particle-particle interaction in sucrose-free dark compound chocolate. Sucrose-free dark compound chocolate had lower sweetness (P < 0.05) and stronger bitterness (P < 0.05) compared to the sucrose compound chocolate. Trehalose was the most suitable sucrose replacer in dark compound chocolate because it resulted in similar rheological and sensory properties as the sucrose-containing dark compound chocolate and greater resistance to bloom formation after 12 weeks of storage.

关键词： Egg white powder   Microwave   Glycation   Foaming   Baking  

摘要： The application of industrial egg white powder (EWP) was limited by the relatively poor foaming properties. Microwave treatment was proposed to be a creative and efficient technology to improve the functionality of EWP. This study focused on the physicochemical properties and baking performance of EWP undergoing microwave treatment at the presence of maltodextrin (MD). The solubility, fluorescent properties, molecular weight and secondary structure of protein were investigated to verify the glycation and structure transformation. The baking performance of the modified EWP was thoroughly investigated by foaming properties, specific volume, water content, microstructure, and sensory analysis. The microwave treated EWP at presence of MD showed smaller particle size and higher surface hydrophobicity than untreated EWP. The result of molecular weight distribution and FTIR spectrum verified the covalent binding of ?OH abundant MD on the EWP molecule. The foaming ability of EWP after microwave treatment was increased from 4.84 mL/g to 6.18 mL/g at the presence of MD. The enhanced hydrophobic interaction and hydrogen bonding between protein molecules were the main beneficial factors affecting foaming properties and baking performance of EWP. This study was meaningful for promoting the application of microwave-assisted glycosylation reaction in the functional modification of proteins.

关键词： cerium dioxide   nanoparticles   precipitation   microemulsion   morphology   zeta-potential  

摘要： A series of CeO2 nanoparticles was synthesized by precipitation in reverse microemulsions in the presence of mixed aqueous-alcoholic solutions at variable and constant medium pH. It is shown that these methods promote the formation of non-agglomerated CeO2 particles with a size less than 15 nm. TEM and XPS methods showed that the ratio of Ce3+ /Ce4+ ions increases on the surface when the size of CeO2 nanoparticles is decreased. The synthesized CeO2 nanoparticles show high stability in aqueous suspensions without using additional stabilizers (zeta > +35 mV), which is important for medical and biological application.

关键词： Ground beef   Black carrot extract   HiOx-MAP   Metmyoglobin   Lipid oxidation   Microbial quality  

摘要： In the present study, firstly, various properties of lyophilized water extracts (LBCWE) produced from fresh black carrot were determined. LBCWE was observed to be a rich source of monomeric anthocyanins (1188.40 +/- 17.38 mg C3G/100 g;n = 4) and phenolics (2733.83 +/- 17.78 mg GAE/100 g, n = 4). Secondly, ground beef containing LBCWE (Control, 100, 200 and 300 ppm) and packaged in HiOx-MAP (80% O-2 + 20% CO2) was evaluated in terms of lipid oxidation, metmyoglobin (MetMb), color, pH and microbial counts during storage at 2.0 +/- 0.5 degrees C for 12 days. By increasing level of LBCWE, the pH, lipid oxidation, MetMb and microbial counts were decreased (P < 0.01). The LBCWE significantly affected the color and microbial count parameters (P < 0.01). The highest redness and lowest microbial growth during storage was in the 300 ppm LBCWE group (P < 0.05). On the 12th day of storage, Pseudomonas and Enterobactericeae decreased 1.24 log and 1.46 log units in this group according to control. The shelf life of ground beef can be extended by 3 days with MAP + 300 ppm extract application.

关键词： Mince size   Surimi gel   Gelling properties   Microwave   Microstructure  

摘要： This study investigated the effects of fish mince size on the gelling properties of silver carp surimi gel produced by microwave heating combined with the water bath method. As the mince size increased, the mince protein and fat contents increased, but the moisture content decreased. Although the strength and water holding capacity of the surimi gel obtained from the larger mince were lower, the detrimental effect resulting from this larger size was considerably reduced by microwave heating;this afforded the fast and selective heating of the heterogeneous surimi. A soft textured compact gel structure was obtained from the 4 mm fish mince based on the results of the texture profile analysis and scanning electron microscopy. These results are anticipated to aid in the formulation of a method for reducing the loss in the processing of muscle fibers to realize the accurate and moderate processing of low-value fish.

关键词： activated carbon   polypyrrole   haemocompatibility   standard contact porosimetry   hydrophilic   hydrophobic properties  

摘要： The effects that conditions of pyrrole electropolymerization on Norit RXS activated carbon (AC) have on the physicochemical and porometric properties and biocompatibility of resulting composite materials are studied. Using the method of standard contact porosimetry, we show that polypyrrole deposited onto AC samples subjected to preliminary conditioning in a pyrrole solution has almost no effect on the distribution of their pore volume with respect to the pore radius, but it does influence their hydrophilic properties;i.e., a longer duration of conditioning makes the surface of composite samples more hydrophilic. The fact that our polypyrrole/AC composites display electrochemical activity, while the initial AC does not, is observed for the first time. This phenomenon is evidence in favor of the formation of electrochemically active complexes on the surface of synthesized composites, and the hypothetical composition of the complexes can be presented as [surface compounds]/[intermediate products of pyrrole electropolymerization]. The considerable influence that microquantities of polypyrrole present on the AC surface (at around 0.13%) have on its electrochemical, hydrophilic/hydrophobic, and adsorption properties suggests that the aforementioned complexes on the surface of composites display electrocatalytic behavior. In addition, the influence of electropolymerization conditions on the activity of composites toward blood cells is revealed.

关键词： Protein   Nanoparticle   Nanofibril   Structural characteristics   Emulsifying activity  

摘要： To date, few studies are found to compare the interfacial properties of protein aggregates with different structures and characteristics. In this research, different whey protein isolate (WPI) aggregates (native, nanoparticles, and nanofibrils) were fabricated, and characterized, and the emulsifying, and interfacial properties of WPI (native), its nanoparticle, and nanofibril as a function of pH values and salt concentrations were systematically investigated. The Z-average diameters of WPI (native), its nanoparticle, and nanofibril were 10, 355, and 122 nm, respectively. The isoelectric point (IEP) of native WPI was found to be approximately 5.0, whereas IEP of nanoparticles was decreased to 4.7, but increased to 5.5 for nanofibrils. WPI nanofibrils exhibited highest emulsifying activity index (EAI) and emulsifying stability index (ESI) at pH 3.0, whereas WPI nanoparticle had the highest EAI and ESI at pH 7.0. Low salt concentrations can increase the EAI and ESI of proteins. The EAI and ESI were highly correlated with the particle size, zeta-potential, and surface hydrophobicity of protein molecules. A negative correlation between interfacial tension of protein molecules and EAIs was observed regardless of protein types.

关键词： Okara   Modified   Dietary fiber   3D printing   Cookie  

摘要： This paper presents a means to modify the attributes of okara fiber using ultrasonic and high-speed shearing treatment. The results of scanning electron microscopy and differential scanning calorimetry reveal that the modified okara fiber demonstrates small particle size and high thermal stability. When the 500 W-15,000 rpm combination is used for okara-fiber treatment, the latter exhibits excellent swelling (SC) as well as water- and oilholding capacities. When 6% of modified okara fiber is added to the dough, the resulting cookies demonstrate the best printing performance. Subsequently, the printing parameters can be optimized to obtain the best filling rate of 30%. The corresponding nozzle diameter and printing speed equal 0.8 mm and 50 mm/s, respectively. Finally, the 3D-printed cookies containing okara fiber are compared against those commonly available in the market via sensory evaluation. As observed, the 3D-printed cookies were more acceptable to people. Therefore, the addition of the okara dietary fiber to the cookie dough not only improves the okara utilization rate but also increases the dietary-fiber content in the cookie, thereby alleviating the occurrence of obesity in modern society.

关键词： Ultrasound pretreatment   Zinc chloride   Thermal modification   Moso bamboo   Dimensional stability  

摘要： Background: To save energy and reduce emissions during the thermal modification of Moso bamboo, this study investigated the effect of the combined zinc chloride-ultrasound pretreatment and thermal modification on the physicochemical properties of Moso bamboo. Methods: Samples were pretreated using 5% (w/w) ZnCl2 solution and 40 kHz ultrasonic waves, followed by heat treatment at 160 degrees C. The samples were characterized by moisture absorption measurements, X-ray diffraction, Fourier-transform infrared spectroscopy, surface wettability measurements, thermogravimetric analysis, and colorimetry. Findings: The results showed that the combined pretreatment method reduced the moisture absorption by 10.15% and increased the relative crystallinity of Moso bamboo cellulose by 4.4%. It also increased the surface contact angle by 25.2%, lowered the onset of thermal decomposition, reduced the temperature required for hemicellulose to reach its maximum thermal degradation rate by 49 degrees C, and increased the color change (Delta E*ab) by 23.60. (c) 2021 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

关键词： Thin layer chromatography   Sunscreens   Soil-water partition coefficient   Bioconcentration factor  

摘要： Y RP-18 TLC chromatography was used to evaluate the impact on the environment (mobility in soil expressed as soil-water partition coefficient, log K-oc;bioconcentration factor in aquatic organisms, log BCF) of several cosmetic raw materials - sunscreens, preservatives and vitamins. The retention parameters R-M(0) (R-M extrapolated to zero concentration of an organic modifier in a mobile phase), S (slope), PC1 (1st principal component) and R-M(75%) (single TLC run parameter for mobile phases containing 75% (v/v) of an organic modifier) obtained for six organic modifiers (methanol, acetonitrile, THF, acetone, dioxane, DMF) were used as the sole descriptors or combined with calculated physico-chemical properties (PSA - polar surface area;M-W - molecular weight;V-M - molar volume) of studied compounds. The chromatographic parameters considered in this study are, generally speaking, good predictors of the compounds' mobility in soil or the affinity for aquatic organisms. The parameters R-M(0), S and R-M(75%) obtained for THF, dioxane and acetone may be used to investigate even very lipophilic compounds. R-M(75%) is of a little bit limited use but it should be considered a time- and cost-effective alternative to the chromatographic parameters obtained by extrapolation or interpolation methods. In the case of some environmental parameters investigated in this study additional descriptors (PSA) have a significant influence on the quality of correlations. (C) 2021 Elsevier Ltd. All rights reserved.