[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,v...[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,vacuum freeze drying,microwave vacuum drying,drum drying and spray drying were measured and analyzed to explore the effects of different drying methods on quality characteristics of Chinese wolfberry powder. [Results] The total sugar content and reducing sugar contents of product: vacuum freeze drying > spray drying > microwave vacuum drying > drum drying > hot air drying; carotene and total flavonoid contents: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; after drying process,the dietary fiber content of product obtained by drum drying and spray drying was relatively higher,while the Vc content of Chinese wolfberry powder prepared by vacuum freeze drying was the highest. a~*value( redness to greenness) of color: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; the Chinese wolfberry powder prepared by vacuum freeze drying had the best solubility,hygroscopicity and rehydration ratio. [Conclusions] Microwave vacuum drying was the best method to prepare Chinese wolfberry powder,in order to keep its quality and consider the cost of production.展开更多
Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. ...Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. The impacts of different sintering temperatures on the structure and electrochemical performances of Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 were compared by means of X-ray diffractometry(XRD), scanning electron microscopy(SEM), and charge/discharge test as cathode materials for lithium ion batteries. The experimental results show that the spherical morphology of the spray-dried powers maintains during the subsequent heat treatment and the specific capacity increases with rising sintering temperature. When the sintering temperature rises up to 900 ℃ , Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 attains a reversible capacity of 153 mA·h/g between 3.00 and 4.35 V at 0.2C rate with excellent cyclability.展开更多
To prepare PZT powder at lower temperature, lead zirconate titanate (PZT) powder (x(Zr)/x(Ti)=56?44) was prepared by wet-dry method. Glycol was used as the solvent, and zirconium oxychloride was used as zirconium sour...To prepare PZT powder at lower temperature, lead zirconate titanate (PZT) powder (x(Zr)/x(Ti)=56?44) was prepared by wet-dry method. Glycol was used as the solvent, and zirconium oxychloride was used as zirconium source. The properties and structure of the powder were analyzed by XRD, SEM and Sedimentograph. The effects of sintering parameter such as sintering temperature, keeping time and heating-up velocity on structure of PZT power were investigated. The results show that homogeneous PZT with single-phase perovskite structure can be obtained after sintering at 730 ℃ for 2 h, and the average size of PZT powder is about 113 nm.展开更多
以活菌数、水分含量、感官品质、消化特性、贮藏稳定性、干燥能耗和得率为指标,探究发酵豆乳粉的最佳干燥方式。结果表明:真空冷冻干燥处理的发酵豆乳粉具有较高的乳酸菌活菌数、抗性淀粉含量和贮藏稳定性,并具有较好的色泽、外观和冲调...以活菌数、水分含量、感官品质、消化特性、贮藏稳定性、干燥能耗和得率为指标,探究发酵豆乳粉的最佳干燥方式。结果表明:真空冷冻干燥处理的发酵豆乳粉具有较高的乳酸菌活菌数、抗性淀粉含量和贮藏稳定性,并具有较好的色泽、外观和冲调性,但其能耗高,生产效率较低;喷雾干燥处理的发酵豆乳粉具有较好的色泽、外观和冲调性,且水分含量低,其乳酸菌活菌数和贮藏稳定性略低于真空冷冻干燥,贮藏6个月后的活菌数仍能保持在7.31 lg CFU/g,且其干燥速度快,能耗小,适于发酵豆乳粉的规模化生产;与其他两种方式相比,45℃热风干燥处理的发酵豆乳粉冲调性和贮藏稳定性最差。综上,考虑到生产效率、能耗优势和产品质量,建议在发酵豆乳粉生产中运用喷雾干燥技术。展开更多
基金Supported by National Science and Technology Support Plan Program(2016-YFD0400704-3)
文摘[Objectives] To study the effects of different drying methods on quality of Chinese wolfberry powder. [Methods] The physical properties and nutritional contents of Chinese wolfberry powder prepared by hot air drying,vacuum freeze drying,microwave vacuum drying,drum drying and spray drying were measured and analyzed to explore the effects of different drying methods on quality characteristics of Chinese wolfberry powder. [Results] The total sugar content and reducing sugar contents of product: vacuum freeze drying > spray drying > microwave vacuum drying > drum drying > hot air drying; carotene and total flavonoid contents: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; after drying process,the dietary fiber content of product obtained by drum drying and spray drying was relatively higher,while the Vc content of Chinese wolfberry powder prepared by vacuum freeze drying was the highest. a~*value( redness to greenness) of color: vacuum freeze drying > microwave vacuum drying > spray drying > drum drying > hot air drying; the Chinese wolfberry powder prepared by vacuum freeze drying had the best solubility,hygroscopicity and rehydration ratio. [Conclusions] Microwave vacuum drying was the best method to prepare Chinese wolfberry powder,in order to keep its quality and consider the cost of production.
文摘Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. The impacts of different sintering temperatures on the structure and electrochemical performances of Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 were compared by means of X-ray diffractometry(XRD), scanning electron microscopy(SEM), and charge/discharge test as cathode materials for lithium ion batteries. The experimental results show that the spherical morphology of the spray-dried powers maintains during the subsequent heat treatment and the specific capacity increases with rising sintering temperature. When the sintering temperature rises up to 900 ℃ , Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 attains a reversible capacity of 153 mA·h/g between 3.00 and 4.35 V at 0.2C rate with excellent cyclability.
文摘To prepare PZT powder at lower temperature, lead zirconate titanate (PZT) powder (x(Zr)/x(Ti)=56?44) was prepared by wet-dry method. Glycol was used as the solvent, and zirconium oxychloride was used as zirconium source. The properties and structure of the powder were analyzed by XRD, SEM and Sedimentograph. The effects of sintering parameter such as sintering temperature, keeping time and heating-up velocity on structure of PZT power were investigated. The results show that homogeneous PZT with single-phase perovskite structure can be obtained after sintering at 730 ℃ for 2 h, and the average size of PZT powder is about 113 nm.
文摘以活菌数、水分含量、感官品质、消化特性、贮藏稳定性、干燥能耗和得率为指标,探究发酵豆乳粉的最佳干燥方式。结果表明:真空冷冻干燥处理的发酵豆乳粉具有较高的乳酸菌活菌数、抗性淀粉含量和贮藏稳定性,并具有较好的色泽、外观和冲调性,但其能耗高,生产效率较低;喷雾干燥处理的发酵豆乳粉具有较好的色泽、外观和冲调性,且水分含量低,其乳酸菌活菌数和贮藏稳定性略低于真空冷冻干燥,贮藏6个月后的活菌数仍能保持在7.31 lg CFU/g,且其干燥速度快,能耗小,适于发酵豆乳粉的规模化生产;与其他两种方式相比,45℃热风干燥处理的发酵豆乳粉冲调性和贮藏稳定性最差。综上,考虑到生产效率、能耗优势和产品质量,建议在发酵豆乳粉生产中运用喷雾干燥技术。
