Wollesenthomsen5897

Orange peels were applied as precursors to synthesize carbon dots (CDs) via a one-step green hydrothermal method. The relationship between quantum yield and volatile oils in 14 different varieties of orange peels were investigated. The CDs showed strong blue fluorescence and were further modified with EDTA. Compared with the CDs, the CDs@EDTA exhibited higher sensitivity for Cr(VI) detection with a LOD of 10 nM. The CDs@EDTA was proved to be an effective fluorescent sensor element for Cr(VI) detection in water samples with recoveries ranged from 92.09% to 104.87% (RSD  less then  5%). Moreover, CDs@EDTA/Cr(VI) system was further developed as a fluorescent "off-on" sensor for ascorbic acid (AA) detection with a LOD of 0.1 μM. Further, the sensor had been successfully applied for the analysis of AA in fresh oranges and commercial orange juices. The recoveries of AA in fresh oranges and orange juices were 92.58-106.76% and 91.54-104.95%, respectively. The aim of this study was to evaluate the potential use of micronized whole wheat flours in breadmaking. click here The micronization process was achieved by a jet mill and flours (JF) of particle size, ranged from 17 to 84 μm, were used. According to the particle size of the JF, the amount of water added to dough changed and ranged from 77 to 84% as it was calculated in farinograph experiments. JF breads had higher bread yield, firmer crumb, higher elasticity, lower porosity and darker bread color compared to control whole wheat bread. Overall a lower particle size of JF resulted in a close structure of bread. According to sensory evaluation, difference among samples was difficult to perceive. During storage JF bread presented lower limiting firmness potential. link2 After all, there is evidence that jet milled flour determined bread physical characteristics and further storage stability. The effects of pressure and temperature on the gelatinization properties of wheat starch were investigated. The long-range crystallinity and short-range molecular order were gradually destroyed under both conditions as the degree of gelatinization (DG) increased. With increasing DG, differential scanning calorimetry (DSC) onset (To), peak (Tp) and conclusion temperatures (Tc) increased for the heat-gelatinized samples but did not change greatly for the pressure-gelatinized samples. At similar DG, pressure-gelatinization resulted in less granule swelling than heat-gelatinization. Lower degree of both heat- and pressure-gelatinization resulted in increased pasting viscosities and gel texture parameters, whereas the opposite was noted at higher DG. We conclude that pressure and heat induced starch gelatinization in different ways, resulting in different gel texture properties. Pressure-gelatinization disrupted both less stable and more stable crystallites, whereas less stable crystallites were preferentially disrupted during heat-gelatinization. The object of this research was to compare the influence of different soy protein products on wheat dough and its gluten characteristics, including soy protein isolate (SPI), texturized soy protein (TSP) and hydrolyzed soy proteins (SPH), all of which with similar protein content. Addition of TSP could increase dough stability and gluten content, but gluten could not be detected when flour was fortified with SPH. During mixing, SPI tended to interact with SDS soluble wheat proteins, SPH tended to interact with SDS soluble and alcohol soluble wheat proteins, and TSP tended to interact with SDS soluble wheat proteins and TSP. A new protein component was observed from TSP fortified dough by SDS-PAGE. Disulfide bonds change confirmed the new linkage formation in blend dough. CLSM micrographs revealed that effect of SPI, SPH and TSP was different, and this difference was responsible for the change of gluten and dough characteristics. This study aimed at exploring the effects of exogenous seed crystals on the starch recrystallization. A-type and B-type seed crystals from rice starch were added to rice starch paste during cooling to analyze the changes in retrogradation process. DSC results indicated that B-type seed improved the uniformity of crystal size and the degree of crystal perfection; it also affected the nucleation mode of retrograded starches at 4 °C, while A-type seed did not affect these properties. The XRD showed that the unit cell was compact, and the crystal grain became larger upon the introduction of B-type seed, while A-type seemed to loosen the cell. The SAXS reflected that B-type seed increased the thickness of the imperfect lamellar structure formed during recrystallization, while A-type seed decreased it. These findings might be due to the molecular segment arrangement on the nuclei growth surface affecting the arrangement of starch molecular segments approaching the nuclei. In this study, the antioxidant activity of germinating Chinese wild rice was found to decline initially, after which it increased. The largest difference in antioxidant activity was observed between the 36-h (G36) and the 120-h germination (G120) stage. We further assessed the dynamic changes in metabolites, phenolic acids, flavonoids, and phenolic biosynthetic genes in germinating Chinese wild rice. Ultra-high performance liquid chromatography-triple quadrupole mass spectrometry revealed that 315 metabolites were up-regulated and 28 were down-regulated between G36 and G120. Levels of p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillin, p-coumaric acid, ferulic acid, and epigallocatechin increased significantly during germination. Gene expression of four phenylalanine ammonia-lyases, one 4-coumarate-CoA ligase, one cinnamoyl-CoA reductase, two cinnamyl alcohol dehydrogenases, one chalcone synthase, and one chalcone isomerase was significantly higher at G120 than at G36 and promoted phenolics accumulation. This study elucidated the biochemical mechanisms involved in antioxidant activity and phenolic profile changes during Chinese wild rice germination. Fermented foods constitute hubs of microbial consortia differentially affecting nutritional and organoleptic properties, quality, and safety. Here we show the origin source of fermentative microbes and fermentation dynamics of kimchi. We partitioned microbiota by raw ingredient (kimchi cabbage, garlic, ginger, and red pepper) to render kimchi fermented by each source-originated microbe pool and applied multi-omics (metataxonomics and metabolomics), bacterial viability, and physiochemical analyses to longitudinally collected samples. Only kimchi cabbage- and garlic-derived microbial inoculums yielded successful kimchi fermentations. The dominant fermentative microbial taxa and subsequent metabolic outputs differed by raw ingredient type the genus Leuconostoc, Weissella, and Lactobacillus for all non-sterilized ingredients, garlic, and kimchi cabbage, respectively. Gnotobiotic kimchi inoculated by mono-, di-, and tri- isolated fermentative microbe combinations further revealed W. koreensis-mediated reversible microbial metabolic outputs. The results suggest that the raw ingredient microbial habitat niches selectively affect microbial community assembly patterns and processes during kimchi fermentation. With people's increasing needs for health concern, rutin and emodin in tartary buckwheat have attracted much attention for their antioxidant, anti-diabetic and reducing weight function. However, the biosynthesis of rutin and emodin in tartary buckwheat is still unclear; especially their later glycosylation contributing to make them more stable and soluble is uncovered. Based on tartary buckwheat' genome, the gene structures of 106 UGTs were analyzed; 21 candidate FtUGTs were selected to enzymatic test by comparing their transcript patterns. Among them, FtUGT73BE5 and other 4 FtUGTs were identified to glucosylate flavonol or emodin in vitro; especially rFtUGT73BE5 could catalyze the glucosylation of all tested flavonoids and emodin. Furthermore, the identical in vivo functions of FtUGT73BE5 were demonstrated in tartary buckwheat hairy roots. The transcript profile of FtUGT73BE5 was consistent with the accumulation trend of rutin in plant; this gene may relate to anti-adversity for its transcripts were up-regulated by MeJA, and repressed by ABA. Water-extractable arabinoxylan (WEAX) could effectively improve the cereal food quality, while its regulatory effect on wheat starch properties has yet to be well-understood. This study selected the WEAX with different molecular weight (Mw) but same branched degree, and comparatively investigated their effects on the gelatinization and retrogradation behavior of wheat starch. The decreased degree of swelling power, solubility and peak viscosity suggested that low Mw WEAX (L-WEAX) could hinder starch gelatinization more evidently compared with high Mw WEAX (H-WEAX), due to the pronounced inhibition effect on amylose leaching and amylose-lipid complex formation. L-WEAX suppressed the recrystallization of amylose and thus the short-term retrogradation. However, H-WEAX mainly retarded the recrystallization of amylopectin, exerting a more significant inhibition effect on the long-term retrogradation. This study could provide a theoretical basis for enhancing the quality and extending the shelf life of starchy foods by selecting the optimum structure of WEAX. The mechanism leading to aroma persistence during eating is not fully described. This study aims at better understanding the role of the oral mucosa in this phenomenon. Release of 14 volatile compounds from different chemical classes was studied after exposure to in vitro models of oral mucosa, at equilibrium by Gas-Chromatography-Flame Ionization Detection (GC-FID) and in dynamic conditions by Proton Transfer Reaction- Mass Spectrometry (PTR-MS). Measurements at equilibrium showed that mucosal hydration reduced the release of only two compounds, pentan-2-one and linalool (p  less then  0.05), and suggested that cells could metabolize aroma compounds from different chemical families (penta-2,3-dione, trans-2-hexen-1-al, ethyl hexanoate, nonan- and decan-2-one). Dynamic analyses for pentan-2-one and octan-2-one evidenced that the constituents of the mucosal pellicle influenced release kinetics differently depending on molecule hydrophobicity. This work suggests that mucosal cells can metabolize aroma compounds and that non-covalent interactions occur between aroma compounds and oral mucosa depending on aroma chemical structure. Degreening is widely used in citrus fruit to extend the market season for economic gains and increase the consumer acceptance. Elevated CO2 was exogenously applied to Satsuma mandarins (Citrus unshiu Marc.) for degreening and its effect on pigment metabolism was investigated. link3 The results revealed 15% CO2 treatment accelerated the citrus fruit peel color change along with the chlorophyll degradation, β-cryptoxanthin and flavonoids accumulation. The expression of CitSGR, CitNYC, CitChlase, CitPPH, CitPAO and CitRCCR genes involved in chlorophyll metabolism and a set of genes involved in producing β, β-xanthophylls were up-regulated by elevated CO2. For flavonoid metabolism, the up-regulated expressions of CitPAL, CitCHS and CitCHI partly explained the increased total flavonoids content. These results showed that 15% CO2 treatment improved the visual appearance of citrus fruits due to its impact on pigment metabolism and also maintained their nutritional value, thus could be employed as a potential commercial technique for citrus degreening.