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31.
Effects of the addition of hemp powder on the physicochemical properties and energy bar qualities of extruded rice 总被引:1,自引:0,他引:1
Extruded rice/hemp mixtures were prepared by mixing defatted and whole hemp powders with rice flour at varying hemp levels (0%, 20%, 30% and 40%). The influence of hemp powder type and level on physicochemical and antioxidant properties was studied. The bulk densities of the extruded rice/hemp samples increased with increase in levels of added hemp powder. The extrudates blended with hemp powder had a lower water absorption index than the control (extruded rice without hemp). The extruded rice/whole hemp had more total phenolics and flavonoids and had a better scavenging effect on DPPH radicals than extruded rice/defatted hemp. The highest potential to inhibit β-carotene oxidation was found in extruded rice/40% whole hemp. Increasing amounts of hemp powder resulted in lower equilibrium moisture content of energy bars. The energy bar made with extruded rice/20% whole hemp was preferred for colour, taste and overall acceptability. 相似文献
32.
This research was initiated to assess the efficacy of gaseous ozone for inactivation Escherichia coli O157:H7, Salmonella typhimurium and Listeria monocytogenes in apple juice. Juice samples with solids content of 18, 36, and 72 °Brix inoculated with a culture cocktail of three foodborne pathogens were treated with gaseous ozone at a flow rate of 3.0 L/min and an ozone generation rate of 0.10, 0.90, 3.51, and 5.57 g/h for 0.5, 1, 5, and 10 min, respectively. The inactivation kinetics of gaseous ozone on foodborne pathogens conformed to the Weibull model. The time required to achieve a 5 log reduction (t5d) was estimated using the parameters of the Weibull model. The t5d increased with increasing solids content of apple juice. The ozone generation rate did not impart a significant effect (p > 0.05) on t5d. Gaseous ozone is effective at inactivating foodborne pathogens in apple juice but the efficacy is dependent on the solids content of the juice sample. 相似文献
33.
34.
Rheological characteristics of two pretreated petroleum pitches, during their transformation to mesophase, have been studied
by using rotalional viscometer. Simultaneously, the formation, growth, coalescence of mesuphase spheres, and the alignment
of coalesced mesophase were observed by Hot-Stage-Cinema-Microscope, discussed with the results of viscosity change and the
Q.I. content. It is found that both pretreated pitches were Newtonian fluids at low temperature, but behaved pseudoplastics
as increase of mesophase content above 390C. Shear thinning behaviour was also apparent in the shear rate range of 1.9–20
sec−1 at temperature above 390C. The apparent viscosity-temperature curves of this pyrolysed pitches were much affected by the
pretreatment conditions. 相似文献
35.
Stephen B. Ryu Ling Zheng Xuemin Wang 《Journal of the American Oil Chemists' Society》1996,73(9):1171-1176
Activation of phospholipase D (PLD) has been linked to accumulation of nonhydratable phosphatides and lipid degradation leading
to soybean seed deterioration during preharvest and postharvest events. This study examined the changes in PLD activity, protein,
and mRNA in soybeans during seed development and germination. RNA blotting analysis indicated that expression of the gene
that encodes PLD was highest during the early and middle stages of seed development. However, the amount of PLD activity accumulated
per cotyledon reached the highest level in mature seeds. During germination and early seedling growth, PLD mRNA was not detected
one day after imbibition, while a significant increase in PLD expression occurred in the cotyledons of three- and seven-day
seedlings. Similarly, PLD activity and protein concentration showed little change during the first day of imbibition and increased
afterward in three- and seven-day seedlings. These results suggested that expression of PLD is developmentally regulated and
that the changes in its amount of activity and protein are controlled primarily at the mRNA level. Immunoblotting analysis
further revealed the presence of PLD variants that were associated with specific stages of seed development and seedling growth.
The PLD variants present in the cotyledons of mature seeds appeared to be distinct from those observed in the early stage
of seed development and in young seedlings. 相似文献
36.
This study is to investigate the factors influencing the alcohol production byKluyveromyces fragilis using the juice of Jerusalem Artichoke tubers.
The cell growth rate and ethanol production rate were stimulated by aeration and by the addition of unsaturated fatty acids
and the cell mass production and the ethanol production were substantially improved.
It was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of alcohol tolerance of
yeast. 相似文献
37.
Nozaki D Kunstmann J Zörgiebel F Weber WM Mikolajick T Cuniberti G 《Nanotechnology》2011,22(32):325703
We present a theoretical framework for the calculation of charge transport through nanowire-based Schottky-barrier field-effect transistors that is conceptually simple but still captures the relevant physical mechanisms of the transport process. Our approach combines two approaches on different length scales: (1) the finite element method is used to model realistic device geometries and to calculate the electrostatic potential across the Schottky barrier by solving the Poisson equation, and (2) the Landauer-Büttiker approach combined with the method of non-equilibrium Green's functions is employed to calculate the charge transport through the device. Our model correctly reproduces typical I-V characteristics of field-effect transistors, and the dependence of the saturated drain current on the gate field and the device geometry are in good agreement with experiments. Our approach is suitable for one-dimensional Schottky-barrier field-effect transistors of arbitrary device geometry and it is intended to be a simulation platform for the development of nanowire-based sensors. 相似文献
38.
L. Hu Y.‐L. Zhao K. Ryu C. Zhou J.F. Stoddart G. Grüner 《Advanced materials (Deerfield Beach, Fla.)》2008,20(5):939-946
39.
Jungki Ryu Sung‐Wook Kim Kisuk Kang Chan Beum Park 《Advanced materials (Deerfield Beach, Fla.)》2010,22(48):5537-5541
40.