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关键词： Wetting   Evaporation time   Evaporation rate   Forest material   Fire retardant  

摘要： Specialists in forest fire extinguishing consider special fire retardants (solutions, suspensions, and emulsions), in addition to water, to be the promising. When discharged from aircrafts, these agents show greater efficiency in suppressing combustion and preventing ignition of forest materials compared to water. However, such agents have been developed through trial and error so far, because no general theory of the effect of aqueous suspensions, solutions, and emulsions on combustion has been developed yet. In addition, there have not been any experimental data to develop physical and mathematical models of processes when a combustion front acts on forest materials after their wetting by special aqueous compositions. In this paper, we studied the wetting behavior of water and four special fire retardants (bentonite suspension, bischofite solution, fire-extinguishing solution FES-5, and foam agent emulsion) on surfaces of leaves, branches, and needles. The lifetimes and evaporation rates of droplets of fire retardants from the leaf surface were determined at 50-110C. The differences were established in the evaporation rate of droplets of typical fire retardants and water without additives. With identical initial droplet sizes of fire-extinguishing suspension, emulsion and solutions, their evaporation times differed significantly.

关键词： Zhenjiang aromatic vinegar   Different rice   Fermentation process   Aromatic compounds  

摘要： The characteristics of Chinese brewed vinegars are influenced by the different raw materials, microbial environment, and special brewing technology. For the first time, this study analyzed and compared the physicochemical properties changes and volatile composition throughout the whole process at different stages of two kinds of vinegars, which were fermented under the traditional production process of Zhenjiang aromatic vinegar with glutinous rice (ZAV) and non-glutinous japonica rice (RV). Other important parameters, such as sugar composition and levels of amino acids and organic acids, were also considered. ZAV and RV differ in their saccharification, alcohol fermentation, acetic acid fermentation, and decoction stages, whereas some similarities emerge in the later stages. Compared to RV, ZAV contains more abundant constituents and rich aroma compounds, which account for their product features and flavor differences. Results of this research may provide guidance for improving the production technology, flavor quality, and food safety of Chinese traditional vinegar.

关键词： Quinoa flour   Defatting   Extruding   Physicochemical properties   Storage behavior  

摘要： Demanding needs for quinoa flour increase rapidly in China in the last years. However, the investigations on quinoa flour are limited. In this study, defatting and extruding treatments were applied to develop novel quinoa flours with improved physicochemical and storage properties. Defatting treatment did not significantly affect the hydration, microstructure, pasting, and rheological properties. However, it revealed an effective means of lipid oxidation prevention. On the other hand, the extruding treatment showed slight affections on proximate composition. The decreased lightness, and increased yellowness, water adsorption index, water solubility index, and swelling power were observed. Furthermore, attributed to the completely starch gelatinization, a smoother surface microstructure, the lowest pasting temperature, the disappeared endothermic process, the decreased viscosity, and the highest tan delta value was obtained for the extruded flour, indicating that this flour had advantages in food formulates for certain food applications, like food for elderly or weaning food. However, extruded quinoa flour showed poor storage behavior for the highest peroxide value and malondialdehyde value. The findings above were hoped to provide a scientific basis for industrial quinoa flour development in the future.

关键词： Physicochemical properties  

摘要： The physicochemical properties, color characteristics, and biogenic amine (BA) concentrations of Konya Green cheese during ripening process with mold were investigated. Four productions were made in different periods, and the samples were analyzed at the end of the cold storage period (0) and on days 1, 3, 7, 15, 21, 24, and 30 of mold ripening. It was found that dry matter, acidity, and salt values tend to increase, whereas pH and a(w) values tend to decrease during the mold ripening period in all production groups. Total BA content increased significantly from 70.91 to 136.95 mg/kg during the ripening period (p < .01). Principal components explained 92.5% of the total variation among the four production group cheese. Based on the Hierarchical clustering analysis, three clusters were obtained: 1st (0, 3, 15), 2nd (1, 24, 30), and 3rd (7, 21). Tyramine, cadaverine, putrescine, and histamine were observed in 2nd cluster as per the PCA. Novelty impact statement The biogenic amine formation and dominancy of the principal biogenic amins through ripening period of Konya Green cheese were determined using RP-HPLC. The predominant biogenic amines determined at the end of the ripening time were tyramine, cadaverine, and putrescine which represent around 81% of the total BA present. To the best of our knowledge, this is the first study for determinig the biogenic amin production of Konya Green cheese.

摘要： Submesoscale eddies and fronts are important components of oceanic mixing and energy fluxes. These phenomena occur in the surface ocean for a period of several days, on scales between a few hundred meters and few tens of kilometers. Remote sensing and modeling suggest that eddies and fronts may influence marine ecosystem dynamics, but their limited temporal and spatial scales make them challenging for observation and in situ sampling. Here, the study of a submesoscale filament in summerly Arctic waters (depth 0-400 m) revealed enhanced mixing of Polar and Atlantic water masses, resulting in a ca. 4 km wide and ca. 50 km long filament with distinct physical and biogeochemical characteristics. Compared to the surrounding waters, the filament was characterized by a distinct phytoplankton bloom, associated with depleted inorganic nutrients, elevated chlorophyll a concentrations, as well as twofold higher phyto- and bacterioplankton cell abundances. Highthroughput 16S rRNA gene sequencing of bacterioplankton communities revealed enrichment of typical phytoplankton bloom-associated taxonomic groups (e.g., Flavobacteriales) inside the filament. Furthermore, linked to the strong water subduction, the vertical export of organic matter to 400 m depth inside the filament was two-fold higher compared to the surrounding waters. Altogether, our results show that physical submesoscale mixing can shape distinct biogeochemical conditions and microbial communities within a few kilometers of the ocean. Hence, the role of submesoscale features in polar waters for surface ocean biodiversity and biogeochemical processes need further investigation, especially with regard to the fate of sea ice in the warming Arctic Ocean.

关键词： basic oxygen furnace gas   CO2 emission reduction   thermodynamic feasibility   vanadia−   titania magnetite ironmaking   waste gas recycling  

摘要： Abandoned basic oxygen furnace gas (ABOFG) is a kind of byproduct fuel resource produced in the basic oxygen furnace (BOF) steelmaking process with a high temperature of 1773-1873 K and 20-40% (vol.%) CO and 20-30% (vol.%) CO2 and is usually ignited and discharged as waste gas (34.7% abandoned rate). The effects and physicochemical phenomena of injecting CO2-containing ABOFG into high-Cr-bearing vanadia-titania magnetite ironmaking are investigated. The thermodynamic calculation shows that the ABOFG injection changes the gas partial pressure and the oxygen potential in the slag-coke interfaces and suppresses the titanium carbonitride formation. According to the results of softening-melting-dripping experiments, the content of titanium carbonitride in the high-titanium slag decreases from 2.53% to 1.14% as the CO2 content in ABOFG increases from 0 to 30%, which is conducive to improving the high-temperature physicochemical properties of molten slag. The recoveries of vanadium and chromium are also improved with the decrease in iron loss. Moreover, the residual coke still maintains a considerable compressive strength with a slight effect from ABOFG injection, which is expected to reduce carbon consumption.

关键词： Extraction  

摘要： The present study explored the hydraulic pressure process as an alternative process to the conventional extraction of date honey. In this regard, response surface methodology (RSM) and central composite design (CCD) were utilized as process optimization tools to achieve the highest yield and efficiency. Independent processing parameters were temperature (50-60 degrees C) and pressure (4-12 bar). Moreover, the effect of optimum conditions on the quality and active compounds of date honey were studied. The results showed that the optimum conditions to give the highest yield (45.83%) and extraction efficiency (87.99%) were a temperature of 60 degrees C and a pressure of 8.83 bar with a come-up time of 6 hr. The pH values of extracted date honey were higher than the conventional method. The change in pH values was described using the first-order kinetic equation. While moisture content and acidity were significantly lower than the conventional method, hydraulic pressure increased the ash, protein, total sugar, reduced sugar, pectin, and total soluble solids. The valorization approach developed in this study provides a platform for producing high-quality date honey as a value-added product from an underutilized date. The findings can help with enhancing resource efficiency through agricultural waste valorization. Practical Applications Hydraulic press extracted the date honey at a pilot scale and showed good potential for further upscaling. This method addressed a significant concern of conventional extraction, that is, quality deterioration. In addition, the hydraulic press enhanced the extraction yield and process efficiency. Furthermore, results elaborated on the effects of processing parameters. Such approaches can be used in the industry to enhance resource efficiency and to help with achieving sustainable development goals (SDGs).

关键词： Amylose content   Texture   Oryza sativa   Ratoon rice   Starch physicochemical properties   Starch structure  

摘要： Ratoon rice (RR) is characterized by higher production combined with enhanced rice quality. However, limited information is available regarding the mechanism of quality enhancement of RR. In this study, three varieties were used to investigate differences in the components, the fine structural and physicochemical properties of starch, and the textural characteristics of cooked rice between the main crop and RR. Compared to the main crop, RR significantly increased the starch and amylose content, amylose to amylopectin ratio, weight average molecular weight of the starch granule, and fa (DP 6-12) and fbl (DP 13-24) chain proportions of amylopectin. However, it decreased the amylopectin and protein content, mean diameter and number average molecular weight of the starch granule, and fb2 (DP25-36) and fb3 (DP > 37) chain proportions of amylopectin. This contributed to an increase in branching degree, polydispersity, Delta Hgel, Tc-R, Delta Hret, and retrogradation percentage, as well as a decrease in the average chain length and polymerization degree of amylopectin and crystallinity degree, and water solubility of RR. These differences might contribute to the increase in hardness and decrease in stickiness of cooked RR.

关键词： Chontaduro (Bactris gasipaes Kunth)   mineral composition   peach palm   SEM   X‐   ray diffraction  

摘要： The functional applications of chontaduro (Bactris gasipaes Kunth) flour and starches depend on its ripeness state. However, there are no reports of the physicochemical properties of chontaduro flours and starches nor their associated fatty acid profile. This research aimed to study the physicochemical properties of ripe/unripe chontaduro flours, isolated starches, and fats. Compared to unripe flour, ripe flour exhibited higher (p<0.05) protein (16.79%) but lower lipid content (-25.72%). Minerals such as K, S, Ca, P, and Mg were the most abundant in the flours (0.025-0.030 g 100 g(-1)). Ripeness did not impact the morphology of the starch granules and its orthorhombic crystalline structure, but the cooking process partially damaged this structure, characteristic of A-type starches. Ripe flour showed higher viscosity than unripe flour, while defatted flour did not exhibit increased peak viscosity due to fatty acid loss. There are no changes in the infrared spectra of the oil from unripe/ripe flour, but stearic, oleic, and palmitic acids were identified. The results suggested that chontaduro flour is an important source of minerals (mainly K, S, Ca, P, Mg, and Na), unsaturated fatty acids, and low-viscosity starch, making it a suitable nutritious ingredient to supplement existing food line under functional terms.

关键词： Acachul   Leathers   Antioxidants   Texture   Sensory-studies  

摘要： The objective of this work was to develop an innovative fruit leather from apple added with a dry ingredient obtained from a wild fruit named acachul (Ardisia compressa Kunt) and sweetened with stevia and maltitol syrup. The acachul ingredient was analyzed in terms of physical properties, and bioactive characteristics: antioxidant capacity (AC), monomeric anthocyanin content (ACY) and total polyphenol content (TPC). Texture, color, and bioaccesibility of AC were evaluated in the developed leathers, together with sensory and stability studies. The powder ingredient was exceptionally rich in bioactive compounds, and it also showed good physical properties. The leather exhibited AC values of 1.64 +/- 0.1, and 1.59 +/- 0.2 mg GAE/g by ABTS and FRAP methods, respectively;and presented an ACY value of 0.50 +/- 0.06 mg Cyn-3-glu/g, a TPC value of 2.80 +/- 0.19 mg GAE/g, and 91.0% AC bioaccessibility. The sensory study showed that 70% of consumers liked the product, this being a valuable data to know the potential of this product in the market. After 12 weeks storage >70% AC was preserved, and texture changes were within the range reported by other authors. This product could be an interesting option to replace conventional candies.