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关键词： Edible pickering emulsion   Complex particle   Desirable stability   Smart delivery system   Tunable digestion   Application trend  

摘要： Background: In recent years, Pickering emulsions have attracted wide attentions due to their enhanced stability and numerous possible applications compared to conventional emulsions. In the field of food science, the application of food-grade particles endows the Pickering emulsions with a broader prospect. Scope and approach: This paper elaborates the factors affecting the stability of Pickering emulsions and summarizes various physicochemical properties of Pickering emulsions. Besides, the available food-grade particles that have been recently developed as Pickering stabilizers are summarized. Furthermore, the applications of edible Pickering emulsions and their future trends are highlighted. Key findings and conclusions: The stability of Pickering emulsions is affected by three factors: particle as Pickering stabilizer, water phase and oil phase. Food-grade particles for Pickering emulsion applications are mainly divided into six categories: polysaccharide particles, protein-based particles, complex particles, flavonoid particles, food grade wax and fat crystals, which can be modified by physical or chemical methods to enhance their Pickering emulsifier performance. Fat substitute, nutraceutical delivery and cleaning agent in replacement of detergents are potential applications of food-grade Pickering emulsions. The research trends of food-grade particle-stabilized Pickering emulsions include Pickering double emulsions, nutraceutical co-delivery, multilayer Pickering emulsions, fixing the Pickering emulsions in the gel, preparation of porous materials and responsive Pickering emulsions. It can be concluded that the food industry will have a great revolution with the development of Pickering emulsions.

关键词： spray drying   powder   dromedary milk   foam capacity   foaming   rehydration  

摘要： In this study, three skimmed and one whole-fat spray-dried camel milk powders were produced and their characteristics were compared to those of bovine milk powders. The physicochemical analysis of the produced powders indicated that camel milk powders (whether skimmed or not) presented higher ash and whey protein contents as compared to those of bovine milk powders. Our results indicated that the investigated camel and bovine milk powders exhibited a high solubility index (>99%) with poor dispersibility and wettability indexes due to their small particles size (d(50) <= 12 mu m) and their narrow size distribution (span <= 2). In addition, although camel and bovine milk powders presented the same total fat content, lower free fat content was measured for camel milk powders. Besides, the whey protein nitrogen index and the SDS-PAGE electrophoresis underlined that camel and bovine milk proteins remained intact after drying with low denaturation extent. It is worth noticed that camel milk proteins were less denaturized due to the absence of the heat-sensitive beta-lactoglobulin in camel milk. Moreover, the low denaturation extent participated in the enhancing of the foaming capacity and stability of camel and bovine milk powders. Finally, the calorimetric analysis showed that higher fat melting temperatures were recorded in whole-fat camel milk powder and in their anhydrous form as compared to those of bovine milk. Practical Application Camel milk powder is an emerging non-bovine dairy product. Understanding its rehydration ability and evaluating the impact of spray drying on its protein quality are promising approaches to obtain high-quality camel milk powder with high reconstitution ability. Findings of this study indicated that spray drying is a suitable technique to produce highly soluble camel milk powders with low denaturation extent. These results will benefit the research and development department of food industry (especially those producing camel milk powder)

关键词： fish cake   haddock   Atlantic mackerel   sensory attributes   quality parameters   nucleotides   NMR metabolomics  

摘要： Research background. It is desirable to increase the consumption of pelagic fish rich in long-chain omega-3 fatty acids. Partial replacement of traditionally used white fish species by pelagic fish will increase the content of omega-3 fatty acids, and thus improve the nutritional value but it may also affect the consumer acceptance. The aim of this study is to assess the physicochemical and sensory quality of novel fish cake prototypes prepared from haddock and mackerel mince. Experimental approach. Fillets of haddock and Atlantic mackerel were used as raw material for preparation of fish cakes. The fish fillets were minced, mixed together (in haddock/mackerel mass ratio of 100:0, 75:25 and 50:50) with salt, potato starch, pepper and full fat milk. Physicochemical and sensory analyses were further performed. Results and conclusions. The fatty acid composition analysis showed that the recommended daily intake of 250 mg of eicosapentaenoic acid and docosahexaenoic acid can easily be reached by consumption of fish cakes enriched with mackerel. The oxidation levels of all fish cakes were low in terms of peroxide value and thiobarbituric acid reactive substance assay (TBARS). Fish cakes prepared with higher mass fraction of mackerel mince (>50 %) had significantly (p<0.05) softer texture than other fish cakes due to higher amount of fat in their formulations. At the same time, these fish cakes were significantly darker than haddock- based (>50 %) fish cakes due to higher myoglobin content in the fish muscle. Moreover, fish cakes with higher amount of mackerel mince had increased yellowness due to the accumulation of water-soluble (r=0.990, p<0.05) and fat-soluble (r=0.976, p<0.05) TBARS. Metabolites relevant for taste and quality were quantified by using H-1 nuclear magnetic resonance (NMR) spectroscopy. The mass fractions of anserine, trimethylamine oxide and beta-alanine decreased, while the mass fractions of histidine, glutamic acid and alanine increased with the addi

关键词： Perilla seed oil   Superheated steam   Seeds microstructure   Oil yield   Quality characteristics   Volatile compounds  

摘要： This study investigated the effect of superheated steam (SHS) treatment on the yield and quality properties, including volatile compounds of perilla seeds oil (PO). SHS treatment resulted in ruptured seed coat and damaged cellular structure, increasing oil yield (78.81 g/100 g seeds), about 2.5-times higher yield than the untreated seeds (33.11 g/100 g seeds). The viscosity (similar to 89 mPa s), color parameters (L*a*b*), acid value (0.19 mg KOH/g), and peroxide value (1.02 meq/kg) of SHS-treated POs were similar with that of the untreated PO, indicating no oil rancidity by SHS treatment. SHS-treated PO showed a dramatic reduction of lipase activity from 37.44 to 0.80 mu mol/g, 3-times higher phenolic content and 5-times higher antioxidant activity than that of the untreated PO. The major volatiles were 2,4-heptadienal, 4-methyl-5-(2-methyl-2-propenyl-2(5H)-furanone, 3-(4-methyl-3-pentenyl)furan perillen, and 3-methylpentane in POs. The normalized relative intensities of the volatiles were reduced for SHS-treated PO. Thus, SHS could be an effective treatment for high oil yield without originating odor characteristics compounds in PO.

关键词： Johanniter   Regent   Indigenous yeast   Wines   Cold climate   Volatile compounds  

摘要： The aim of the study was the physicochemical characterization of wines produced using indigenous yeasts isolated from spontaneously fermented grape musts, obtained from cold climate *** cerevisiaeMH020215 andNakawazaea ishiwadaeMG971259 yeast strains were used in this study. The musts obtained from white and red grapes of Johanniter and regent varieties were used as a fermentation raw material. In the produced wines, content of ethyl alcohol, total extract, sugars, free amino nitrogen was analyzed, along with determination of total and volatile acidity and volatile compounds profile. Additionally, organoleptic evaluation was performed. Wines obtained with nativeS. cerevisiaeMH020215 strains were characterized with more favorable enological properties. Synthesis of desirable volatile compounds, especially esters, contributed to the creation of desirable aromatic profile of those wines. Moreover, those beverages contained higher levels of carbonyl compounds (especially acetaldehyde) and lower methanol content. Wines obtained usingN. ishiwadaeMG971259 cultures were represented by high total acidity level and substantial fusel alcohol content (mainly butanol, propanol), which resulted in an unfavorable sensory profile of the product.

关键词： Chemical Exchange Saturation Transfer   Computational Studies   Density Functional Theory   Water Residence Lifetime   Longitudinal and Transverse relaxivity   Fluorescence quenching  

摘要： Contrast enhancement in MRI using magnetization or saturation transfer techniques promises better sensitivity, and faster acquisition compared to T-1 or T-2 contrast. This work reports the synthesis and evaluation of 5-HT1A targeted PARACEST MRI contrast agent using 1,4,7,10-tetraazacycloDOdecane-4,7,10-triacetAMide (DO3AM) as the bifunctional chelator, and 5-HT1A-antagonist methoxyphenyl piperazine (MPP) as a targeting unit. The multistep synthesis led to the MPP conjugated DO3AM with 60% yield. CEST-related physicochemical parameters were evaluated after loading DO3AM-MPP with paramagnetic MRI active lanthanides: Gadolinium (Gd-DO3AM-MPP) and Europium (Eu-DO3AM-MPP). Luminescence lifetime measurements with Eu-DO3AM-MPP and computational DFT studies using Gd-DO3AM-MPP revealed the coordination of one water molecule (q = 1.43) with metal-water distance (r(M)-H2O) of 2.7 angstrom and water residence time (tau(m)) of 0.23 ms. The dissociation constant of K-d 62 +/- 0.02 pM as evaluated from fluorescence quenching of 5-HT1A (protein) and docking score of -4.81 in theoretical evaluation reflect the binding potential of the complex Gd-DO3AM-MPP with the receptor 5-HT1A. Insights of the docked pose reflect the importance of NH2 (amide) and aromatic ring in Gd-DO3AM-MPP while interacting with Ser 374 and Phe 370 in the antagonist binding pocket of 5-HT1A. Gd-DO3AM-MPP shows longitudinal relaxivity 5.85 mM(-1)s(-1) with a water residence lifetime of 0.93 ms in hippocampal homogenate containing 5-HT1A. The potentiometric titration of DO3AM-MPP showed strong selectivity for Gd3+ over physiological metal ions such as Zn2+ and Cu2+. The in vitro and in vivo studies confirmed the minimal cytotoxicity and presential binding of Gd-DO3AM-MPP with 5-HT1A receptor in the hippocampus region of the mice. Summarizing, the complex Gd-DO3AM-MPP can have a potential for CEST imaging of 5-HT1A receptors.

关键词： alloy   nickel–   tin   titania   corrosion   biocidal properties  

摘要： Abstract- The morphology and composition of Ni-Sn and Ni-Sn-TiO2 coatings have been studied by scanning electron microscopy and energy-dispersive X-ray analysis. The electrochemical behavior of the obtained coatings in a 3% NaCl solution has been examined. The influence of the inclusion of titania in the Ni-Sn coating on the mechanical and antibacterial properties has been revealed. Dependences of the influence of incubation time and exposure to UV radiation on the concentration of living bacteria cells on the surface of the Ni-Sn-TiO2 coating have been established. In bacterial tests with Ni-Sn-TiO2 coatings deposited from the electrolyte containing 2 g/L TiO2, the concentration of viable Staphylococcus aureus decreases from 130 to 90 CFU/mL and from 70 to 30 CFU/mL without and with UV irradiation, respectively.

关键词： Edible mushroom   Beef paste   Flavor compound   Protein oxidation   Lipid oxidation  

摘要： The effects of four edible mushrooms, Volvariella volvacea (Vv), Hypsizygus marmoreus (Hm), Pleurotus ostreatus (Po) and Agaricus bisporus (Ab), on beef paste quality were investigated. In this experiment, 50 g/kg dried mushroom powders were added to the beef paste, separately. The results showed that Vv and Po could reduce the hardness, chewiness, and gumminess of beef paste. Both free amino acid and volatile compound contents of the samples exhibited remarkable changes after mushroom powders were added. Compared with the control, the total free amino acid contents increased 1.31-, 1.10-, 1.67- and 1.14-fold and the essential amino acid contents increased 2.51-, 3.31-, 4.41-, and 1.69-fold in the beef samples treated with 5% Vv, Hm, Po and Ab, respectively. Up to 35 volatile compounds were identified in beef paste with 5% Vv, while only 14 volatile compounds were detected in the control. The mechanism was ascribed to the flavoring substances and the enzymes in the edible mushrooms. The above results indicated that edible mushrooms not only supply flavor components but also promote the formation of flavor substances in meat products.

摘要： Bacterial communities are closely related to soil physicochemical properties in urban green spaces, which also are important biological indicators in urban soil quality. However, there has been little basic research on soil bacterial composition and network analysis in different urban green space types, leading to a lack of micro-understanding during urban green space management. Therefore, 30 soil sample sites from 0 to 40 cm were separately selected from two primary urban green space types (attached and park) in Beijing. We investigated how soil bacterial communities and networks respond to soil physicochemical properties by using high-throughput 16S rDNA sequencing. Soil moisture content, organic matter (OM), total N (TN), available N, available K (AK), total Pb, and total Hg in park green space soils were significantly increased 1.49, 2.04, 1.78, 1.46, 1.20, 1.84, and 7.19 times relative to attached green space soils. A total of 2,238,221 sequences (440 bp) were acquired from urban green space soils. norank_c_Acidobacteria, Blastocatellaceae_Subgroup_4_, Gemmatimonadaceae, Anaerolineaceae, and Nitrosomonadaceae were the major bacterial families, and soil OM (36.6%, P = .01) and TN (34.6%, P = .01) were significantly (P < .01) positively correlated with bacterial communities at the family level in urban green soils. Through network analysis, we determined that Actinobacteria was the core microorganism in parks and attached green space soils, but taxonomic groups in park green space soils tended to be more modular and more closely connected. Therefore, we should pay more attention to promoting development of soil nutrients in urban green spaces, especially attached green spaces. Our results provide scientific guidance for urban green space ecological environmental management.

关键词： zeolite-bearing (ZBT) tuffs   magnetite   ferritization   phase composition   sorption properties  

摘要： The paper presents data on the comparative assessment of the composition and properties of natural and magnetized zeolite-bearing tuffs (ZBT) from the Kholinsky, Transbaikalia, and Chuguevsky, southern Russian Far East, deposits in Russia. In addition, the composition and properties of magnetite synthesized by two methods and used for ferritization of ZBT were determined. The phase composition of the synthesized magnetically active material and the quantitative phase composition of natural and magnetized samples of the ZBT from the Kholinsky and Chuguevsky deposits were determined by X-ray powder diffraction. The composition of rock-forming minerals of the ZBT from the Kholinsky deposit was refined. The chemical composition of ZBT from the Kholinsky and Chuguevsky deposits and the initial and magnetized samples was analyzed by XRF. Magnetite content on the surface of the ferritized ZBT was demonstrated to be no higher than 5-7% and not to be able to affect the capacity of ZBT and the pH of the solution. Magnetization of the ZBT does not affect the structure and properties of the ZBT.