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关键词： Crystallinity  

摘要： This work is focused on the modification of insoluble dietary fiber from pomelo (Citrus grandis) peel (PP-IDF) by ball milling. Ball milling intensified water and oil holding capacity and water swelling capacity by 43.7%, 65.1%, and 107.5%, respectively. Besides, 97.1% of taurocholic acid, 45.3% of glucose, and 9.3 mu g/mg of NO2- were bound by milled insoluble dietary fibers (IDFs). The oil-in-water Pickering emulsions were successfully emulsified by ball-milled PP-IDFs. The ball-milled PP-IDF for 2.0 hr (PP-IDF-BM2h) exhibited higher stability after storage owing to its relative strong electrostatic and steric repulsions intensified by milling process. A simulated three-stage gastrointestinal tract (GIT) model was employed to explore the physical stability of emulsion in the digestive system. Ball milling contributed promotion on stability emulsion but ion strength in simulated liquids predominated in affecting zeta potential. Overall, ball milling extended green protocols for modification of properties for dietary fiber, providing a promising application in food industry. Practical applications For safety consideration, materials used for food processing should be in low toxicity with less employment of chemicals. Hence, it is essential to develop a green and renewable strategy to modify properties of dietary fiber (DF) in food applications. Ball milling is a simple and low cost strategy that can effectively improve or modify physicochemical properties including crystallinity, surface potential, water and oil holding capacities, and hydrophilic and hydrophobic properties. Importantly, ball milling can treat dietary fiber in batch processing with no waste and chemicals, which is suitable for industrial applications.

关键词： Drying  

摘要： The drying of pumpkin puree by convective (C) and foam-mat (FM) was investigated (45/65 degrees C). The FM drying provides 50% higher drying rates than convective at the same temperature. Both drying beds were porous. The FM bed was thinner than the convective, and structures associated with bubbles collapsing in the drying process were observed in its surface. All flours showed hygroscopic behavior, and high water-holding capacity (6.9-7.7 g water g/dw), but a lower monolayer water content was observed in foam-dried samples (0.04-0.06 g water g/dw). The FM drying at 45 degrees C produced flours with equivalent carotenoids content (855 mu g beta-carotene g/dw(1);p <= .05) than fresh puree, which may be associated with shorter drying periods observed. The flours progressive rehydration (25/40 degrees C) produced puree with the same firmness and adhesiveness as fresh puree. This result reveals the potential of foam-bed drying to make pumpkin flours, adding value to this raw material. Novelty impact statement For the first time, the foam-mat drying of "Tetsukabuto" pumpkin puree was studied and this method, at the same temperature, provides around 50% faster drying rates than the conventional hot-air drying. Although, the study is innovative using scanning electron microscopy (SEM) to register the foamed and nonfoamed dried bed, sharing differences in these bed morphologies. The foam-mat drying preserved the carotenoid content in dried puree, the flour presented high water-holding capacity and higher solubility index, and the rehydrated flour has the same firmness and adhesiveness as a fresh puree.

关键词： Water-soluble melanin   Squeezed grapes   Obtaining   Physico-chemical properties  

摘要： Recently, there has been a revival of interest in the use of natural pigments in various industries. It is of great interest to obtain melanins from plant raw materials. An effective method has been developed for cleaning grape squeezes from impurities before the alkaline extraction of melanin. A schematic flow diagram of the isolation and purification of water-soluble melanin from grape squeezes is presented. The obtained pigment was identified by spectroscopic methods. It has been established by thermal treatment that the amorphous precipitate of melanin is stable at temperatures up to 120 degrees C, and the acid resistance of the obtained melanin solution is in the pH range of > 4.0. Gel filtration, electrophoresis and HPLC showed that the pigment preparation contained four fractions that differed by their molecular weights. The quantitative distribution and the molecular weights of the obtained melanin fractions were determined. Qualitative reactions and spectroscopic methods have shown that these fractions are typical melanins. The elemental composition of the obtained melanin and its antioxidant properties, the amino acid composition of the melanin protein, and its solubility were determined. The yield of melanin from the feedstock was 17.3%. Based on the physicochemical properties of the resulting melanin, it can be used as an effective natural food coloring and powerful antioxidant substance.

关键词： Aspergillus oryzae   co-inoculation   non-salt-tolerant lactic acid bacteria   soy sauce  

摘要： Soy sauce fermentation is largely mediated by bacteria, including several non-salt-tolerant bacterial species. The present study aimed to compare the use of Aspergillus oryzae alone or in co-inoculation with Lactobacillus plantarum or Enterococcus faecalis on the resulting enzymatic activity, content of phenolic compounds, free amino acids, organic acids, and antioxidant capacity of soy sauce. Co-inoculation significantly increased acid protease, beta-glucosidase, and pectinase activities during koji making. Additionally, the contents of total phenols, total flavonoids, organic acids, amino acids, isoflavones, as well as the antioxidant capacity were higher during moromi fermentation using co-inoculants compared to those obtained when A. oryzae was used as single inoculant. Overall, co-inoculation of A. oryzae with L. plantarum or E. faecalis during koji making was shown to effectively promote the production of active substances in soy sauce. Practical Application In this study, Aspergillus oryzae in mixed inoculation with Lactobacillus plantarum or Enterococcus faecalis could be effectively used in koji making for soy sauce. The use of co-inoculants in koji making effectively promoted the production of active substances in soy sauce, hence it is improving health benefits, whilst diversifying the use of raw materials and the application value of soybean meal.

关键词： Rhodosorus   Rhodophyta   Polysaccharides   Extraction   Optimization   Antioxidant activity  

摘要： Microalgal polysaccharides have been reported in many studies due to their uniqueness, biocompatibility, and high value, and Rhodosorus sp. SCSIO-45730 was an excellent source of polysaccharides and beta-glucans. However, the polysaccharides from the red unicellular alga Rhodosorus sp. SCSIO-45730 have barely been studied. In this work, hot water extraction of Rhodosorus sp. SCSIO-45730 polysaccharides (RSP) was optimized using response surface methodology (RSM) based on Box-Behnken design (BBD). The maximum RSP yield (9.29%) was achieved under the optimum extraction conditions: liquid-solid ratio of 50.00 mL g(-1);extraction temperature of 84 degrees C;extraction time of 2 h;and extraction times of 5 times. The results of physicochemical characterization showed that RSP had high sulfate and uronic acid with content of 19.58% and 11.57%, respectively, rough layered structure, and mainly contained glucose, galactose, xylose, and galacturonic acid with mass percentages of 34.08%, 28.70%, 12.46%, and 12.10%. Furthermore, four kinds of antioxidant assays were carried out, and the results indicated that RSP had strong scavenging activities on ABTS and hydroxyl radical and moderate scavenging activities on DPPH and ferrous chelating ability. These results indicated that RSP showed potential as a promising source of antioxidants applied in food, pharmaceutical, and cosmetics industry.

关键词： Water recycling   Crop irrigation   Pharmaceuticals and personal care products   Ionization behavior   Atrazine metabolites  

摘要： Passive uptake of contaminants of emerging concern (CECs) and its relationship with physicochemical properties, such as lipophilicity (LogKow), ionization behavior (pKa), distribution coefficient (LogDow) and transpiration rate are scarcely studied. In the current study, hydroponically grown corn (Zea mays) was exposed to carbamazepine (CBZ), fluoxetine (FLX), gemfibrozil (GBZ), triclosan (TRI) and atrazine (ATZ)) at environmentally relevant concentrations (20 mu g/L each one). Plant tissue concentrations of CECs were determined several times over 21 days. Eighteen plants were used, nine exposed to the CECs and nine untreated. Whole plants were harvested at 7, 14 and 21 days and separated into roots, stem, leaf and male bud flower (only at 21 days). Hydroponic solution was maintained at pH 5.5 throughout the study. CECs concentrations in the exposure solution and tissues were determined by LC-MS/MS. ATZ metabolites desisopropylatrazine (DIA) and desethylatrazine (DEA) were determined by LC-DAD. In shoot tissues, CBZ, FLX and ATZ were detected, while TRI and GBZ were detected only in roots. Root concentrations were related with LogKow (R-ROOT(2) = 0.415). Leaf and stem concentrations of CBZ, FLX and ATZ were linked with LogKow and strongly linked with pKa. Transpiration was related with CBZ and ATZ in shoot, but not related with FLX shoot levels. Neutral compounds such as CBZ (pKa = 13.94;100% neutral) and ATZ (pKa = 1.6;85% neutral) were taken up passively with transpiration. Root accumulation was related with CECs lipophilicity, while translocation and bioaccumulation in shoot were not only related with lipophilicity, but also with CECs ionization behavior and transpiration.

关键词： anodic dissolution   combination electrode   aluminum   titanium   oxide system   Al2O3   TiO2   fluoride ions   chloride-containing electrolyte  

摘要： The electrochemical behavior of a combined titanium-aluminum electrode in aqueous solutions of 1.0 M sodium chloride with additions of hydrofluoric acid has been studied. It is shown that, under open-circuit conditions, the combined electrode is a short-circuited element, the surface of which is practically equipotential and is characterized by the value of the potential located between the values of the corrosion potentials of aluminum and iron electrodes. With a low content of hydrofluoric acid, practically the entire anode current flows through the surface of the aluminum component of the combined electrode. In addition, with an increase in the HF concentration to 0.5 M, the titanium electrode is activated and the fraction of the current flowing is almost the same as the fraction of the current of the aluminum component of the anode. This makes it possible to regulate the dissolution rates of aluminum and titanium during their joint oxidation during the synthesis of precursors of metal oxides of a given phase composition by changing the ratio of the areas of the anode components.

关键词： antioxidant   beardless barb   fermentation   Ka-pi-plaa   protein degradation  

摘要： Production of Thai fish paste Ka-pi-plaa fermented using beardless barb, Cyclocheilichthys apogon was monitored. The physicochemical, microbiological and antioxidant properties were compared after each process, that is autolysis, salting, sun-drying and fermentation. Colour parameters L* decreased while a* and b* increased during production (P < 0.05). The Ka-pi-plaa finished product presented an intense brown colour as shown with the increase in browning intensity (A(420)). Contents of formal nitrogen, ammonia nitrogen and amino nitrogen showed continuous increase (P < 0.05) indicating the formation of peptides and free amino acids, which were verified by protein patterns. Populations of total, halophilic, proteolytic, lipolytic and lactic acid bacteria (LAB) generally increased. Halophilic bacteria grew rapidly after salting. LAB counts were correlated with the pH change. It was suggested that a few biochemical reactions occurred during production, including protein hydrolysis by microbial and fish proteases, lipid oxidation as presented by the increasing thiobarbituric acid reactive substances value, and Maillard reaction based on the determined precursors and products. Antioxidant activities generally increased during production particularly fermentation, suggesting Ka-pi-plaa possessed 2,2-diphenyl-l-picrylhydrazyl and 2,2-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) scavenging and metal chelating activities, and ferric reducing power. This study provides important information on the relationship among production steps, various properties and chemical reactions for fish fermentation.

关键词： Animals  

摘要： This study evaluated the addition of green tea extract (GTE) and its effect on the physicochemical, microbiological, and sensory properties of chicken patties. Hydro-ethanolic extracts (E1, E2, E3, and E4) showed higher total phenolic and flavonoid contents than the aqueous extract (E5). Then, E1 extract was chosen for 2,2-diphenyl-picrylhydrazyl (DPPH) analysis (showed 75.73% inhibition of DPPH radical), and it was added to chicken patties at concentrations of 0% (control), 0.5% (GT-0.5), and 1.0% (GT-1.0) and analyzed during refrigerated storage. Lower cooking yields and hardness values were observed in GT-1.0. GTE effectively delayed lipid oxidation of chicken patties. Redness parameters were affected, and this was also noted in sensory analysis. However, GT-1.0 showed lower microbiological parameters until day 7 of storage. Therefore, the addition of 0.5% GTE reduced discoloration and lipid oxidation without impacts on sensorial parameters, so is a viable option for the processing of chicken patties. Practical applications Results from this study showed the potential of green tea extract (GTE) addition in chicken patties to improve physicochemical, microbiological, and sensory properties during storage. The obtained GTE has been analyzed and E1 (extraction conditions of 75% ethanol-water, 15 min at 80 degrees C) showed higher phenolic, flavonoid, and antioxidant activity. The addition of 0.5% (GT-0.5) has proven to be the best alternative for application on chicken patties hence was effective to retard lipid oxidation and improve color stability. In addition, no significant impact on sensory attributes were observed when compared to control treatment. Despite the positive effects on patties lipid oxidation, the addition of GTE at any level was not able to retard the microbial spoilage during the storage. In this context, GTE arises as an alternative for producing chicken patties with lower synthetic conservatives.

关键词： Yttria   Plasma erosion   Crystalline orientation   Plasma etching   EBSD  

摘要： A physicochemical mechanism acting between the reactive plasma and the material surface controls the erosion of polycrystalline ceramics in fluorine containing etching plasmas. In this study, a Y2O3/YOF composite was exposed to a fluorine etching plasma. Relocalization enables the direct correlation of crystalline orientation with material response. Our study reveals an orientation dependent surface fluorination of Y2O3, which controls the etching resistance and morphology formation. Orientations near the low index planes (001), (010) and (100) exhibit the lowest stability due to a homogeneous surface reaction. The presented results help to extend the mechanistic understanding of the plasma-material interaction of Y2O3.