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101.
102.
Effects of High-Pressure Pretreatment and Calcium Soaking on the Texture Degradation Kinetics of Carrots during Thermal Processing 总被引:3,自引:0,他引:3
ABSTRACT: Carrots ( Daucus carota ) pretreated under different high-pressure conditions were thermally processed at temperatures in the range of 90°C to 110°C. Texture degradation (hardness) was monitored objectively using a texture analyzer. For a given thermal treatment, the rate constant (k-value) decreased with increasing pretreatment pressure. A high-pressure pretreatment (200 to 500 MPa) at 60°C for 15 min resulted in a more pronounced texture improvement compared with the same pretreatment at 20°C and 40°C, respectively. Calcium impregnation conferred more beneficial effects when applied immediately after the high-pressure pretreat-ment. The observed changes in texture characteristics were associated with the degree of methylation of carrot pectins, which is dependent on pectinmethylesterase (PME) activity. 相似文献
103.
104.
Hao QI Gao-shao CAO Jian XIE Xin-bing ZHAO 《Frontiers of Materials Science in China》2008,2(3):291-294
Spinel LiMn2O4 particles were successfully coated with CuO, MgO, ZnO, Al2O3 and CeO2 by a melting impregnation method. Except for the CeO2-coated sample, all the others exhibit better cycling stability than bare LiMn2O4 at room temperature and at 55°C. Among these samples, the ZnO-coated sample shows the best cycling stability. A capacity
of 100 mA·h·g−1 still remained after 100 cycles at 55°C while the bare LiMn2O4 retains a capacity of only 80 mA·h·g−1 after the same number of cycles. The improvement in the cycling stability is attributed to the suppressed Mn dissolution
caused by HF. 相似文献
105.
106.
It is shown that porous materials such as paper can be impregnated with a conducting polymer by first soaking the paper in
a solution of metal salt which acts as an initiator for subsequent polymerization. By using this procedure the conductivity
of filter paper can be raised to as high as 2 (ohm cm)−1 for an FeCl3/H20/pyrrole combination. The role of the metal ion is discussea and it is pointed out that the impregnated papers exhibit both
ionic and electronic conductivity. The polypyrrole paper composites exhibit some properties similar to carbon black-polymer
composites. 相似文献
107.
108.
《Drying Technology》2006,24(12):1649-1656
The effect of sucrose solution concentration and vacuum/atmospheric pressure periods on the mechanical properties of apples (Gala var.) was studied through a stress relaxation test. The empiric model proposed by Peleg was used to fit the curves and the parameters a (level of relaxation) and b (relaxation rate) were evaluated. The experimental results obtained in this study showed that vacuum impregnation conditions had a great influence on the final mechanical properties of the apples. The Peleg model fitted well the data from the stress relaxation curves and may be useful for assessing sample deformation resulting from the vacuum impregnation process. 相似文献
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110.