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关键词： ZrO2–   Y2O3–   CeO2–   Al2O3–   CoO   ZrO2 solid solution   phase transformations   CoAl2O4   blue ceramics   microstructural design  

摘要： Variations in the phase composition, specific surface area, and morphology of structural components in the ultrafine powder of composition (wt.%) 70 (90 ZrO2 (3 Y2O3, 2 CeO2)-10 Al2O3)-30 CoAl2O4 (70ZA30CoA), produced by hydrothermal synthesis combined with mechanical mixing, were studied in the heat treatment process up to 1300 degrees C. The study employed Xray diffraction, scanning and transmission electron microscopy, petrography, and BET. The formation of CoAl2O4 in the 70ZA30CoA powder in the heat treatment process was accompanied by reversible phase transformations: T-ZrO2 -> M-ZrO2 -> T-ZrO2. The M-ZrO2 content increased from 15% to 46% in the temperature range 850-1000 degrees C and decreased to 13% after heat treatment to 1150 degrees C. The process involved slight coarsening of the primary T-ZrO2 particles, while the size of the primary M-ZrO2 particles remained practically unchanged. The phase transformation was due to a decrease in the free energy of the ultrafine 70ZA30CoA powder, representing a thermodynamically nonequilibrium system. The phase composition changed color of the 70ZA30CoA powder in the following sequence: gray -> gray blue -> dark cyan -> bright blue. Morphological analysis of the structural components showed that the CoAl2O4 formation and reversible T-ZrO2 -> M-ZrO2 phase transformation were accompanied by shape change, loosening, and subsequent sintering of the agglomerates. The chain-like agglomerates of various shapes and sizes indicate that the 70ZA30CoA powder sinters actively at 1300 degrees C. The decrease in the specific surface area from 46 to 1 m(2)/g depending on the heat treatment temperature was determined by the development of three structural transformation processes: formation of CoAl2O4, phase transition of the ZrO2 solid solution, and sintering of the 70ZA30CoA powder. The established regularities are of fundamental importance for the microstructural design of ZrO2 composites such as ZrO2-Y2O3-CeO2-Al2O3-CoO materials

关键词： digestibility rates   Dioscorea   molecular structures   physicochemical properties   starches  

摘要： Starches are isolated from tubers ofDioscoreaandOxalis tuberosa(OT) grown in Hidalgo and surrounding areas. The starch particle sizes ofDioscorea bulbifera(DB) show a bimodal distribution, whereas those ofDioscorea mexicanaSchidw (DM) and OT show unimodal distributions. TheDioscoreastarch granules have a round shape, while those of OT have an elongated shape. Significant differences (p < 0.05) in pasting properties among the starches are observed, with DB showing the lowest viscosity value and DM showing the highest viscosity value. The peak and pasting temperatures show similar patterns, with higher values observed in theDioscoreastarches than in the OT starch. The gelatinization temperature values are low in the DB starch, compared to the DM and OT starches, which is consistent with the small granule size in DB. The interval in amylose content in the starches is 25.9% to 32.3%, classifying as normal starches. Molecular analysis reveals differences in molar mass and gyration radius between the amylopectin and amylose fractions of the starches, parameters that influence the physicochemical, pasting, and enzymatic hydrolysis characteristics of starches. The characterization of the tuber starches in this study reveals the potential of these under-used food crops.

关键词： beta-carotene   apricots   juice powders   maltodextrin  

摘要： In this study, apricot juice powders (AJPs) are obtained via freeze-drying using different maltodextrins (MDs) as carrier agents. The Hacihaliloglu cultivar, which is the most common variety in Turkey, is used as an apricot sample. Three different MDs: low (4-7), medium (13-17), and high (17-20) dextrose equivalence (DE) are used as the carrier agent. The powders obtained are subjected to accelerated oxidation at 55 degrees C, and the stability of beta-carotene in the AJPs is determined. Some physicochemical properties, such as the glass transition temperature, microstructure, bulk density, color, moisture, solubility, degree of caking, and hygroscopicity, are also determined. The results show that after a 20 day period of oxidation, the remaining beta-carotene in the control sample is 24% of the initial value, whereas for low, medium, and high DE MD samples, it is measured to be 47%, 60%, and 57% of the initial concentration, respectively. There is no significant difference in the content of surface carotenoids between the control and the samples with added MD. In contrast, according to other quality attributes like hygroscopicity, caking, moisture content, and solubility, the best results are obtained from the low DE MD sample.

关键词： NaCl   Substitutes   Element content   Microstructure  

摘要： The effects of NaCl substitutes (KCl and Ca-ascorbate) at a certain concentration (15%) on the salted pork microstructure were investigated. The changes of water, salt, element (Na, K and Ca) content and total weight in salted pork under different kinds of salts, concentration and salting time were also discussed. Results show the different treatments significantly affected the element content of salted pork. Under high concentration (20%) salting, the relationship with corresponding element content is K (5.08%) > Na (2.73%) > Ca (0.82%). In the mixed salt solution, Ca element significantly inhibited the content increases of Na than K, and sodium salt substitution with potassium and calcium salts significantly reduced the sodium content in salted pork. The relationship of specific surface area in pork salted with three kinds of salts (15% concentration) is KCl group (4.3011 m(2)/g) > NaCl group (4.2902 m(2)/g) > Ca-ascorbate group (4.2319 m(2)/g). K, Na, and Ca have a certain impact on the microstructure, which affects the increase of salt content in salted pork.

关键词： Environmental DNA   In situ microbial community   Next-generation sequencing   Persistent toxic substance   In vitro bioassay   Sediment pollution  

摘要： The environmental DNA (eDNA) metabarcoding was applied to assess benthic ecological health in the west coast of South Korea by investigating a long-term microbial community change (2015-17). The ecological interaction among microorganisms, from phylum to family level, and their associations to environmental variables across the five regions were highlighted. As part of the study, the available chemistry and toxicological data in the regions during the monitoring periods were incorporated into an integrated sediment triad assessment. The bacterial communities were dominated by Proteobacteria (34.2%), Bacteroidetes (13.8%), and Firmicutes (10.8%). Proteobacteria and Bacteroidetes dominated consistently across regions and years, while Firmicutes and Cyanobacteria significantly varied by region and years (p < 0.05). The abundance of this phylum declined over time with the increasing abundance of Cyanobacteria, indicating their independent interactions to certain environmental changes. Planctomycetes and Gemmatimonadetes linked to some contaminants (Sigma PAHs and Cu), implying indicator taxa. Overall, eDNA-based microbial community analysis combined with exposures of con-taminants and responses of microorganisms is a promising strategy for the assessment of benthic ecological health in contaminated sediments from coastal waters.

关键词： arginine modification   Ganoderma lucidum   medicinal mushroom   melanin   physicochemical and biochemical properties  

摘要： Melanin is a hydrophobic biomolecule produced widely in fungi. Compared with other fungi, health benefits have been associated with medicinal mushrooms, which may provide an excellent source of natural melanin. Nevertheless, the hydrophobicity of melanin may limit its applications. Consequently, the present study was carried out on isolation of melanin from the medicinal mushroom Ganoderma lucidum (GLM) and modification with arginine to improve its solubility. The physicochemical and biochemical properties of melanin were evaluated including structural characterization, solubility, stability, antioxidant activities, and inhibitory effect on pancreatic lipase activity. Arginine-modified melanin showed better solubility, higher color value, stronger antioxidant activity, and stronger inhibitory effect on pancreatic lipase activity in vitro than GLM. In addition, both have good stability in the dark and natural light. These results opened possibilities for providing an excellent source of natural melanin in health food or food additives fields.

关键词： Yuzu peel pectin   De-esterification   Hydrogel beads   Quercetin delivery system   Colon target  

摘要： The aims of this study were to produce de-esterified pectin from yuzu (Citrus junos) peel by enzymatic treatment, to use de-esterified yuzu peel pectin (DEYPP) to prepare hydrogel beads as quercetin delivery systems for colon target, and to estimate the structural, physicochemical, and in-vitro release properties of the hydrogel beads. Yuzu peel pectin was de-esterified by pectin methylesterase (DE: 34.64%), and oligochitosan-DEYPP hydrogel beads were produced by an ionic gelation method with different concentrations of DEYPP (1, 1.5, and 2%). The new formations of cross-linking (between the -COO- of DEYPP and Ca2+) and a polyelectrolyte complex (between the -COO- of DEYPP and the -NH3- of oligochitosan) in all the beads were confirmed by Fourier Transform Infrared analysis. The results of X-ray diffraction and differential scanning calorimetry analysis showed that the crystalline quercetin was converted into an amorphous state during the preparation of hydrogel beads. Both the mean particle diameter and the quercetin entrapment efficiency of the beads were significantly increased with increasing DEYPP concentration. For all beads, the cumulative quercetin release after exposure to simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was below 1%, because both the cross-linking and the polyelectrolyte complex occurred in the beads were stable in the SGF and SIF. However, when the hydrogel beads were exposed to simulated colonic fluid for 12 h, quercetin was greatly released from the hydrogel beads (65.37-99.54%). These results revealed that oligochitosan-DEYPP hydrogel beads can be effectively used as quercetin delivery systems for colon target.

关键词： Pork meat   Kinetics   Thermosonication   B. cereus spores   Physicochemical properties  

摘要： B cereus was extracted from pork meat and detected using conventional polymerase chain reaction, (PCR). The spores were infected in the pork and the inactivation behavior was scrutinize by thermal (80 degrees C and 90 degrees C), sole ultrasonication, US (20 kHz) and thermosonication (TS), at single frequency TSsf (20 kHz, 70 degrees C) and multi-frequency TSmf (20/40/60 kHz, 70 degrees C) using a maximum power of 300 W over a period of 25 min. The most convenient and time-saving treatment method of the infected pork were investigated. TSmf proved to be favorable treatment method as it gave a 4.16 log CFU/ml spore reduction within 5 min. The various treatments were modelled to predict the best fit for the study. Weibull model gave the best fitness and the various parameters showed the effectiveness of the treatments as follows: thermal (80 degrees C) < thermal (90 degrees C) < US (20 kHz) < TSsf (20 kHz, 70 degrees C) < TSmf (20/40/60 kHz, 70 degrees C) for the deactivation of B. cereus spores in pork. Finally, US and TSmf methods enhanced the physicochemical properties (pH, texture and color) of pork.

关键词： acha   Digitaria exilis   Digitaria iburua   gluten free   iburu   underutilized species   underutilized starch   whole grain cereal  

摘要： Fonio grains are a type of small-seeded cereals native to Western Africa and are important cereal crops for food security. The two species are white fonio (Digitaria exilis) (commonly called acha) and black fonio (Digitaria iburua) (commonly called iburu). As a novel food, fonio has attracted attention from other parts of the world due to their attractive nutritional properties (e.g., in whole grain form and being gluten free) and potential food applications. The information regarding the functional properties and applications of fonio is rather scattered. This review summarizes the chemical composition, physicochemical and nutritional properties, and diverse food applications of fonio. The nutritional composition and processing properties of fonio are similar to other cereals. Fonio has potential to be complementary to major cereals for diverse food uses. There are research opportunities to better explore fonio grains for value-added applications.

关键词： Supercritical carbon dioxide   Foaming properties   Egg white   Pressure  

摘要： Supercritical carbon dioxide (SCCD) is a green, novel and practical technology in food processing. In this paper, SCCD treatment was used for enhancing the foaming properties of egg white. The possible mechanism of SCCD pressures increasing the foam ability of egg white protein (EWP) was discussed. The results showed that the maximal foaming capacity (107.7%) was obtained at 9 MPa, which was 3.6 times that of original egg white. Electrostatic force of protein molecules was reduced due to the change of pH value. Meanwhile, the particle size of EWP increased and the absolute zeta potential decreased with SCCD pressure increasing. These changes resulted in an increase of hydrophobicity and viscosity of EWP accordingly. This study found that SCCD treatment caused the exposure of EWP hydrophobic groups through the synergy of high pressure and CO2 solvent. It provided a novel path to improve the foam ability of EWP by physical technology.