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71.
Effects of ascorbic acid addition on the contents of retinyl palmitate isomers in skim milk treated with or without 3 mg/mL added riboflavin were studied during storage for 30 h under fluorescent light. Light illumination induced the reduction of all-trans-retinyl palmitate and 13-cis isomer, but promoted the production of 9-cis isomer in the skim milk. Riboflavin increased the reduction of all-trans-retinyl palmitate, but decreased the formation of 9-cis isomer in lightstored skim milk. The addition of ascorbic acid greatly inhibited the light-induced reduction of all-trans-retinyl palmitate and 13-cis isomer in skim milks. Ascorbic acid also greatly increased the formation of 9-cis-retinyl palmitate in skim milks during light storage. 相似文献
72.
SOLUBILIZATION OF APPLE POMACE BY EXTRUSION 总被引:1,自引:0,他引:1
JAE-KWAN HWANG JUNG-SUN CHOI CHUL-JIN KIM CHONG-TAI KIM 《Journal of Food Processing and Preservation》1998,22(6):477-491
Apple pomace (AP), a fibrous by-product of apple juice processing, was solubilized by a twin-screw extruder. AP was extruded under 14 different operating conditions, where the process variables are controlled in the following ranges: screw speed, 250–350 rpm; feed rate, 30–40 kg/h; moisture, 20–30%. Water soluble index (WSI) increased linearly with specific mechanical energy (SME). Soluble dietary fiber of extruded AP also increased with SME, which in turn decreased the content of insoluble dietary fiber (IDF). As a result, total dietary fiber (TDF) remained nearly unchanged. Water holding capacity (WHC) remained nearly constant at low SME, but markedly deceased at high SME due to disintegration of cell wall. Gel filtration of WSP exhibited the structural fragmentation of cell wall by extrusion: the higher SME, the higher fragmentation of SME. Ion exchange chromatography of WSP demonstrated that increasing SME resulted in increasing the extractability of free neutral polysaccharides from the cell wall of AP. It was also found that the degradation of AP cell wall by extrusion preferentially occurred at the arabinogalactan sidechains of pectins. 相似文献
73.
MIE SOON LEE-KIM EUN SUN HWANG KYUNG HYUN KIM 《Journal of Food Processing and Preservation》1997,21(6):485-494
The inhibitory effect of 4-hexylresorcinol (HR), ascorbic acid (AA), citric acid (CA), and bisulfites on polyphenol oxidase (PPO) of burdock roots was studied. HR was an effective inhibitor at low concentrations used in this study for crude PPO from root slices. A binary mixture of HR and AA at 1.0% concentration for 5 min achieved more than 90% inhibition of crude PPO. AA also showed high antibrowning activity for the purified PPO comparable to that of bisulfites, whereas its activity was much lower than that of HR in the crude extract. The inhibitory effect of the combined use of inhibitors was overall in the decreasing order of HR+AA, HR+CA and AA+CA, irrespective of the crude PPO or the purified PPO from burdock slices. 相似文献
74.
A total 264 pork loins were selected to represent a wide range of pork quality of the longissimus thoracis et lumborum. CIE L*C*h color space showed a closer relationship to the subjective color score than L*a*b*color space. Lightness (L*) was the best measure to predict water-holding capacity (WHC). There were highly significant (p < 0.001) correlations between the measures of color and WHC, and curvilinear relationships between either WHC and color or pHu were observed. In normal muscle color range (reddish-pink), there was considerable variation in WHC. Within the RSE + RFN groups of muscles, less variation of WHC could be accounted for by variations in color measurements. Color and WHC were not closely related and suggest that the RSE (reddish-pink, soft, exudative) condition should be classified as a separate quality category of pork muscle. 相似文献
75.
ZHANG Zai-xuan WANG Jian-feng LIU Hong-lin XU Hai-fen DAI Bi-zhi LI Chen-xia LI Lan-xiao GENG Dan INSOO S. KIM 《光电子快报》2007,3(6)
A 31 km long range distributed optical fiber Raman photon temperature sensor (DOFRPTS) system have been developed based on temperature effect of the amplified spontaneous Raman scattering in fiber, and using fiber laser as a pumped source. The results show that temperature measuring uncertainty is ±2 ℃, temperature resolution is 0.1 ℃, measurement time is 432 s, spatial resolution is less than 4 m. 相似文献
76.
This work demonstrates high-performance and current crowding-free InGaN/GaN light-emitting diodes (LEDs) using an electrically-reverse-connected Schottky diode (SD) and an Mg-delta (δ) doped layer.Poss... 相似文献
77.
A serial filtration system was developed for separating immunoglobulin from egg yolk (IgY). Egg yolk was diluted 10 times with water, adjusted to pH 5.0, frozen, then thawed. The diluted yolk was diafiltered through a hard filter paper at 4-6°C to produce a clear water-soluble fraction (WSF). The WSF was then delipidated by filtering through a hydrophobic membrane filter. Ultrafiltration of delipidated WSF at pH 9.0, at 4-6°C, in the presence of 1.5M NaCl resulted in electrophoretically pure (>90%) IgY with a recovery of about 92%. Advantages of this method are the use of only a few mild chemicals and the potential of developing a continuous process. 相似文献
78.
79.
To increase battery life in IEEE 802.16e systems, it is essential to efficiently manage energy in mobile stations. The sleep-mode operation in power management helps to increase the life of a station by saving energy consumption. In power management, there are two important performance metrics energy consumption and the response delay of awakening medium access control (MAC) service data unit (SDU). While in a base station (BS) initiation of awakening, the two performance metrics should be simultaneously considered, in a mobile subscriber station (MSS) initiation of awakening, the response delay is not considered because it is self-operational. There performance metrics are affected by the minimum sleep interval (Tmin), the maximum sleep interval (Tmax), and the average interarrival time of awakening MAC SDUs (TI) during sleep-mode operation. Therefore, it is imperative to evaluate the two initiations of awakening depending on TI. To reach a fuller understanding of the performance, this paper shows an analytical mode and simulations results for the standard sleep-mode operation in the IEEE 802.16e MAC. 相似文献
80.
The use of design method considering a coil temperature to maximize the thrust density of a double side coreless permanent
magnet linear synchronous motor (PMLSM) was presented. The optimal current density where the coil temperature reaches an allowable
temperature with heat analysis was applied to a magnetic circuit design. Changing optimal current density is verified whenever
the design parameters of the motor are altered. The design parameters of the motor were applied to thrust calculation. In
this way, the optimal model, which is a reversal of the existing design method, is deduced. The results were compared with
the experimental data to verify their validity. When the convection heat transfer coefficient is applied to other models,
the results of the analysis and test values show good concordance. The method proposed has some limitations. 相似文献