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排序方式: 共有2212条查询结果,搜索用时 14 毫秒
921.
《Food research international (Ottawa, Ont.)》2005,38(3):289-296
The effects of cholesterol and Tween 80 on the physical stability of empty liposomes were investigated. Results showed that the physical stability of liposomes, including electrostatic and steric stability, was improved by addition of cholesterol and Tween 80. Liposomes prepared by different methods, thin-film hydration, thin-film sonication, reverse-phase evaporation and freeze-thawing, were tested for their capacity to encapsulate ferrous sulfate. Technology parameters to microencapsulate ferrous sulfate, concentration of ferrous sulfate, hydrating media and sonication strength, were optimized. The concentration of ferrous sulfate and the hydrating medium had a significant effect on the amount of encapsulated ferrous ions. The encapsulation efficiency (EE) of 67% was obtained by using the reverse-phase evaporation method. In milk fortified with ferrous sulfate liposomes, the concentration of iron increased to 15 mg L−1, and it was stable to heat sterilization (100 °C, 30 min) and storage at 4 °C during one week. 相似文献
922.
Nanomaterials are often introduced to improve the properties of polymers. In this article, the effects of SiO2 nanoparticles with lager specific areas and special microstructural characters on the properties of starch films were investigated. Firstly, the ultrasonic mixing was used to disperse the SiO2 nanoparticles under different dispersion times, and then the dispersed SiO2 nanoparticles with various ratios were added into starch size. The effects of the dispersion time and the SiO2 content on the mechanical properties of the SiO2/starch composite size were analysed. It was found that the dispersion time and the SiO2 content had significant effects on the tensile and abrasion behaviour of the nanocomposite films. The mechanism of the enhanced mechanical properties of the composite films was examined by analysing the size of the dispersed SiO2 nanoparticles in the dispersion, the surface characters of the films and the structures of the fractured surfaces. And the morphology of the abraded surface was analysed by atomic force microscopy, scanning electron microscope and video zoom microscope. 相似文献
923.
To overcome the shortcomings existing in the roller drafting system of air jet spinning, a set of combing roller-drafting system has been introduced to substitute the roller drafting system in air jet spinning. Moreover, a funnel-shaped fibre conveyer, a disc fibre collector and a swirl twister have been designed to accomplish the spinning process, which was named disc swirl spinning. Experimental spinning proves that combing roller drafting device wears little. Its remarkable advantage lies in the high efficiency of drafting. The rotational speed of jet stream in nozzle can be well utilized, which promises a high productivity. The relationship between the drafting process parameters of disc swirl spinning and yarn properties, such as tenacity and peeling-off-resistance, has been investigated and the data suggest that yarn properties keep stable when combing roller speed is 6000–7000 rpm, feeding quantity is 1.695–2 g/min, sliver linear density is 2–2.58 g/m, feeding tension is 0.012 N and the unwinding tension of the core filaments is 0.06 N. Furthermore, the appearance of disc swirl spun yarn is compared with that of air jet spun yarn. The scanning electron microscope (SEM) photos show that yarn structure of disc swirl spun yarn is similar to that of air jet spun yarn. The core is bound by the outer fibres and it is nearly parallel and no twist. However, the outer fibres of disc swirl spun yarn cover yarn body totally, which is different with that of air jet spun yarn. 相似文献
924.
Zhiqing Gong Bhesh Bhandari Arun S. Mujumdar Sun Jin-Cai 《International Journal of Food Properties》2013,16(5):1066-1073
The rheological behavior of cabbage pulp was determined using a computer controlled rotational rheometer at a temperature range of 20, 30, 40, and 50°C. The flow behavior of pulp was pseudoplastic and fitted well to the Casson model. In all the cases, the effect of soluble solids on apparent viscosity was more pronounced than the effect of temperature. The combined effect of temperature and soluble solid content on viscosity was also given. The activation energy value of 3–6°Brix cabbage puree varied from 7 to 12.6 kJ/mol when shear rate increased from 1 to 10 s?1. The exponential model developed had an excellent fit (r2 > 0.87) and would be useful for the engineering applications. 相似文献
925.
Yanyang Xu Min Zhang Dingyu Tu Jincai Sun Lequn Zhou & Arun S. Mujumdar 《International Journal of Food Science & Technology》2005,40(6):589-595
To obtain dehydrated bamboo shoot slices of high quality, a two‐stage hybrid method of drying was tested to see if it could be cost‐effective. While freeze‐drying provides the best quality bamboo shoot it is a very expensive process. In this study, the drying techniques (a) hot airflow drying followed by vacuum freeze drying and (b) the reverse of the process (a) were examined. The quality of bamboo shoots dried by process (b) was found to be approximately equal to that of freeze‐dried bamboo shoots but at a significantly lower cost. This paper reports results comparing the two processes in terms of energy consumption and the physico‐chemical properties of the dried bamboo. 相似文献
926.
很多植物中都含有酚类物质,它很容易与蛋白质相结合,因此酚类物质是各种植物蛋白产品色泽和风味的一个主要影响因素,并且它也会影响食品蛋白质的功能性质和营养特性。黄酮类化合物是麦胚中最主要的酚类物质。本文以脱脂麦胚为原料,通过两种不同的方法制备脱脂麦胚可溶性蛋白组分,测定各蛋白组分中黄酮类化合物的含量,并尝试通过醇洗的方法脱除黄酮。实验结果表明:制备获得了三种脱脂麦胚可溶性蛋白组分:清蛋白、球蛋白和分离蛋白,三种蛋白组分的蛋白质含量均超过80%。小麦胚清蛋白中的黄酮类化合物含量最高,分离蛋白次之,球蛋白含量最低。黄酮类化合物可能主要是与麦胚清蛋白相结合。采用50%的冷乙醇对麦胚可溶性蛋白进行洗涤,洗涤三次可以脱除90%以上的黄酮类物质。 相似文献
927.
928.
929.
以虾壳为原料生产热反应型调味料的研究 总被引:1,自引:0,他引:1
应用排序检验法、评分检验法对热反应产物进行感官评定后,确定了制备虾调味料的基本反应原料,即以虾壳蛋白酶解液为主要原料,添加木糖与葡萄糖组成的还原糖、精氨酸与丙氨酸组成复合氨基酸;运用单因素实验和正交实验,得到了热反应的优化工艺条件:反应pH值7.0,反应温度110℃,反应时间30 min。反应产物具有浓郁的虾的风味。 相似文献
930.
南瓜渣的微波真空干燥 总被引:10,自引:1,他引:10
加工南瓜汁时得到大量的副产品南瓜渣,南瓜渣富含具有生物活性功能的β-胡萝卜素和膳食纤维,是一种值得开发和利用的保健食品资源。文中采用微波真空干燥,力求最大程度保存β-胡萝卜素。在不同微波功率和压强条件下测定水分含量和β-胡萝卜素含量,得到干燥曲线以及β-胡萝卜素失活曲线。研究结果表明,提高微波功率可以大大提高干燥速度。通过增加压强可以提高干燥速度,但会加快β-胡萝卜素的失活。在668.37W和4 000Pa条件下干燥时,β-胡萝卜素的保留率最高,达到92.31%。通过对3个干燥模型的比较,得出Page模型能较好地描述南瓜渣的微波真空干燥特性。 相似文献