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To investigate the impact of oxygen for the feature parameters of the coal oxidation process, the coal samples were selected from mines of Liuhuanggou and Ewirgol in Xinjiang Province, China. TGA/DSC–FTIR was employed to conduct the coal mass, heat, and functional groups under oxygen concentrations of 3, 6, 9, 15, and 21 vol% from 30 to 950 °C. In the entire coal–oxygen reaction, the characteristic temperatures were divided into T1 (adsorption temperature), T2 (oxygen-adsorption mass-gain starting temperature), T3 (oxygen-adsorption mass-gain maximum temperature), T4 (ignition temperature), T5 (max mass loss rate temperature), and T6 (burnout temperature). The results indicated that with the decrease in oxygen concentration, the feature temperature point gradually transferred to the high-temperature area. The coal samples maximum exothermic temperature rose, the maximum exothermic power decreased, and the net thermal release decreased along the entire reaction process of coal sample. The feature temperature excursion of the coal–oxygen composite reactive incurred the hysteresis effect, which was obvious when the oxygen concentration was 3 vol%. Furthermore, the content of main functional groups of coal microstructure was the highest at T2, and the content gradually decreased with the temperature increase continuously. As the increase in oxygen concentration, the content of main functional groups increased. Among them, there was no considerable change in the hydroxyl content in the coal microstructure on the characteristic temperatures of 75, 140, and 350 °C. As the temperature rose to 140 °C, the content of main functional groups with a varying degree grew. When the temperature reached 350 °C, the oxygen-containing functional group began to decrease.

Glucosamine-glycosylated zein (GLZ) generated by transglutaminase was developed as a novel delivery vehicle to prepare lutein-loaded glycosylated zein nanoparticles (GLZ-LUT). GLZ-LUT exhibited a polydispersed spherical microstructure, lutein was embedded into GLZ to form nanocomplexes via self-assembly, they had a lower zeta potential and an average particle size of less than 200 nm. Compared to lutein-loaded zein nanoparticles (Zein-LUT), the lutein entrapment efficiency of GLZ-LUT was increased from 81.55% to 89.60%. Infrared spectroscopy (FTIR) analysis results confirmed that zein was successfully modified and that lutein was encapsulated by hydrophobic zein and GLZ. Moreover, GLZ showed significantly higher solubilization of lutein than Zein-LUT and significantly improved the in vitro release of lutein in the simulated gastrointestinal tract. The in vitro antioxidant activity of lutein was also enhanced by the encapsulation of zein and glycosylated zein. These findings indicated that GLZ represent a potentially efficient and promising nanodelivery carrier for lutein compounds.

Turnip is a vegetable that has many health promoting effects. To diversify the usage and increase the consumption of turnip, the effects of hot air drying, infrared drying, explosion puff drying and freeze drying (FD) on the volatiles of turnip chips were studied. The volatiles of fresh turnip and dried turnip chips were isolated by HS-SPME–GC–MS and a total of 67 volatiles were identified. However, the volatiles in turnip chips dried by different methods are quite different. Based on principal component analysis and hierarchical cluster analysis, the volatiles of fresh turnip were distinguished from those of the dried chips and FD was separated from the other drying methods. As the result of orthogonal projection on latent structure-discriminant analysis (OPLS-DA), isothiocyanato-cyclopropane and (2-isothiocyanatoethyl)-benzene were identified as the characteristic volatiles of fresh turnip. While, 2-azido-2,3,3-trimethyl-butane and hexanal were identified as the characteristic volatiles for FD dried chips.

Effects of four different drying methods on the colour, texture, sensory quality, microstructure, bacterial viability and storage stability of probiotic-enriched apple snacks were assessed. The drying methods were air drying (AD), freeze drying (FD), freeze drying followed by microwave vacuum drying (FD+MVD) and air drying followed by explosion puffing drying (AD+EPD). Overall, FD+MVD can be used as a suitable drying method for the development of probiotic enriched apple snacks in consideration of colour, texture, sensory quality, bacterial viability and storage stability. Probiotic bacteria in FD+MVD-dried samples remained above 1×106 CFU g−1 for 120 days at 25°C. Interestingly, bacterial viability in FD+MVD-dried samples turned out to be significantly higher than FD-dried samples during storage for 120 days.

Ultrasound treatment has been widely applied in the extraction of biologically active compounds including carotenoids. However, there are few reports on their effects on the stability of these compounds. In the present study, the stability of all-trans lutein, one of the carotenoids, was investigated under the action of ultrasound. Results showed that ultrasound induced the isomerization of all-trans lutein to its isomers, namely to 13-cis lutein, 13'-cis lutein, 9-cis lutein and 9'-cis lutein as analyzed by HPLC coupled with DAD and LC-MS; and the percentage of the isomerization increased with increasing both ultrasonic frequency and power. The stability of all-trans lutein in dichloromethane was worst among multiple kinds of solvents. Interestingly, the retention rate of all-trans lutein improved as the temperature increased, which runs counter to the Arrhenius law. Under ultrasound irradiation, the degradation mechanism might be different with various temperatures, the degradation of all-trans lutein followed first-order kinetics at 20°C, while second-order kinetics was followed at 30-50°C. As the ultrasonic reaction time prolonged, lutein epoxidation nearly occurred. Those results presented here emphasized that UAE techniques should be carefully used in the extraction of all-trans lutein.

Blueberry anthocyanins are considered protective of eye health because of their recognized antioxidant properties. In this study, blueberry anthocyanin extract (BAE), malvidin (Mv), malvidin-3-glucoside (Mv-3-glc), and malvidin-3-galactoside (Mv-3-gal) all reduced H

Stability of microencapsulated marigold lutein under three different storage conditions (dark and vacuum, light and vacuum, air and light) at 4, 20, and 37°C was investigated. Major lutein stereoisomers, including all-trans lutein, 13-cis lutein, 13′-cis lutein, 9-cis lutein, and 9′-cis lutein, were rapidly separated within 12 minutes by reverse-phase C30-HPLC-PDA using methanol, methylene chloride, and acetonitrile as eluent, which could provide more explicit information for identifying and distinguishing stereoisomers. The content of all-trans lutein decreased during storage time for all the treatments, and the degradation of all-trans lutein fitted the first order model as correlation coefficients (R2) were higher than 0.95, microencapsulated marigold lutein with vacuum packed were preserved best in dark and 4°C storage.

Effects of thermal and low intensity ultrasound combined with heat (LIUH) pretreatment prior to microwave vacuum drying on enzyme inactivation, color changes and nutrition quality properties of dried daylilies were investigated. The peroxidase (POD), ascorbic acid oxidase (AAO) and polyphenoloxidase (PPO) thermal and LIUH (0.2 and 0.4W/cm2) inactivation were determined and compared at 70, 80 and 90°C. Significant reduction in the POD, AAO and PPO activity was seen in daylilies after an ambient LIUH pretreatment than thermal pretreatment. POD, AAO and PPO thermal and LIUH inactivation followed the first order kinetics. LIUH pretreatment had a more positive influence on maintaining color of dried daylilies than thermal pretreatment. Furthermore, LIUH pretreatment resulted in a significant increase in chlorophylls, carotenoids (lutein, zeaxanthin and β-carotene), and a decrease in degree of browning and 5-hydroxymethylfurfural (HMF) when compared with thermal pretreatment. The antioxidant activity and contents of several nutritional components of dried daylilies pretreated by LIUH were also higher than that of dried daylilies pretreated by thermal pretreatment. This study provides a basis for the design of LIUH conditions to control vegetables browning and color changes prior to drying processing.

Summary The effects of fermentation on protein, in vitro protein digestibility (IVPD), amino acid, total phenolics, phytic acid and colour values of four maize cultivars (two bi-colour waxy corn and two super sweet corn), namely Jing Tian Zi Hua Nuo NO. 2, Jing Tian NO. 3, Bright Jean and Su Ke Hua Nuo 2008, were determined and compared with those of their unfermented counterparts. Results showed that fermentation caused significant increase in protein (43.5% largest increase), most kind of amino acid (131.5% largest increase in lysine content) and total phenolic content (23.4% largest increase), but significant reduction in phytic acid content (24.3% largest reduction) of four maize cultivars. The IVPD of four maize cultivars, except Suke2008, did not change significantly. Colour values of two waxy corn were resulted in the increase in a-values and reduction in L-values.

The effects of fermenting, boiling, and steaming processes on the levels of free amino acids, organic acids, antioxidant properties (FRAP and DPPH), phenolic compounds, and angiotensine converting enzyme (ACE) inhibition of sweet potato tips were investigated. Seventeen free amino acids were found in the tips. Fermenting, boiling, and steaming processes significantly reduced total free amino acid contents and steaming processes caused smaller losses than fermenting and boiling processes. Five organic acids were investigated in the tips. In comparison with the total organic acid content of unprocessed sweet potato tips, steaming and boiling processes significantly reduced it, while fermenting process increased it. Chlorogenic acid, rutin, and quercetin were investigated in the tips. The total phenolic compounds contents of sweet potato tips significantly increased by steaming and boiling processes, but a substantial loss was caused by fermenting process. A similar result was shown in FRAP value. The result of ACE inhibitory activity indicated that boiling, steaming, and fermenting processes significantly increased ACE inhibitory activity.

Volatile compounds in fresh and fermented sweet potato tips at 0, 10, 20, 30, and 40 d during fermentation were investigated. A new parameter named “relative odor activity value (ROAV)” was applied in evaluating the contributions of volatile compounds to flavor, considering odor threshold. The results showed that volatile compounds could be clustered in the following chemical families: alkenes (most of them were sesquiterpene), alcohols, aldehydes, ketones, and esters in decreasing order. During fermentation, the concentrations of alkenes and ketones were increased and then decreased continuously. Alcohols and esters were increased; while the concentrations of aldehydes decreased. Interestingly, fermenting processes (0–20 d) may contribute to the increase of alkenes and ketones. Major compounds that were identified in all samples include α- and β-caryophyllene, β- and γ-elemene, and β-cubebene (in decreasing order). The changes of their concentrations during fermentation were the same as that of alkenes. Caryophyllene was abundant in all of the samples examined. It has anti-tumour, anti-inflammatory and anti-pests activities. It can mediate interactions among plant, herbivores and their natural enemies. β and γ-elemene, which have been used as antitumor drugs, have not been reported previously as volatiles from sweet potato tips. β-cubebene with antioxidant activity can be used as natural preservatives in food and/or by the pharmaceutical industry.

BACKGROUND: Uniform design was used to optimize the ultrasonic-assisted extraction of cordycepin from cultured Cordyceps militaris. The peak area of cordycepin identified using high performance liquid chromatography (HPLC) at a detection wavelength of 260 nm was considered the detection index. Three factors, ethanol concentration, extraction time and volume ratio of solvent to sample were studied. Optimal quadric polynomial step by step regression was applied to process the experimental results. RESULTS: Results show that the main factors affecting cordycepin extraction yield were the volume ratio of solvent to sample, extraction time and ethanol concentration, in that order. Cordycepin extraction yield reached a peak with ethanol concentration 20.21%, extraction time 101.88 min, and volume ratio of solvent to sample 33.13 mL g−1. An extraction model was developed based on the findings. CONCLUSION: A direct, reliable and accurate assay has been developed for the quantification of cordycepin in cultured Cordyceps militaris by a HPLC-DAD method. The validation procedure confirmed that this method is appropriate for the quality control of cordycepin. Results show that the uniform experimental design approach is useful for finding polynomial functions describing the relationships between variables and responses and to find the best experimental conditions for the extraction of cordycepin in the experimental domain considered. Copyright © 2007 Society of Chemical Industry

The ultrasound-assisted synthesis of lutein disuccinate from all-trans lutein (AL) and succinic anhydride (SA) was investigated in this study. Triethylamine was used as the catalyst. Based on the single-factor experiments, a 7-level-3-factor uniform design and response surface analysis were further employed to evaluate the effects of the selected variables including molar ratio of SA/AL, reaction time and ultrasonic power on the yield of lutein disuccinate. The results indicated that the data were adequately fitted into a second-order polynomial model; the molar ratio of SA/AL significantly affected the synthesis of lutein disuccinate, whereas reaction time and ultrasonic power did not. Based on ridge max analysis, the optimum condition for lutein disuccinate synthesis was predicted to be the molar ratio of SA/AL 265.3:1, ultrasonic power 300 W and reaction time 131.6 min with the lutein disuccinate yield of 80.53 ± 0.18%, which give a 43.8% increase compared with the traditional method, and also significantly shorten the reaction time.