排序方式: 共有55条查询结果,搜索用时 109 毫秒
1.
为了研究乌鳢胶原肽在6种不同离子强度诱导下聚集的结构与特性的变化规律,对聚集体变化过程中的内源荧光、浊度、微观结构、粒径、黏度及其二级结构进行测定。结果表明,在0~500 mM的Na Cl范围内,离子强度具有促进胶原蛋白肽自组装聚集的效果,且聚集速率随离子强度的增大而增加。在0~150 mM范围内,胶原蛋白肽聚集的三维网络紧密性增加,聚集体平均粒径增大74.42%,最大剪切黏度增加487.67%。当离子强度在150~500 mM范围时,胶原蛋白肽三维网络紧密性降低,聚集体平均粒径下降,最大剪切黏度降低21.39%。胶原蛋白肽聚集体的二级结构并没有随离子强度变化而发生明显变化。因此,适度的增大样品离子强度可促进胶原肽的自组装聚集,改善其凝胶的三维网络结构和理化特性,为胶原蛋白肽进一步应用于制备药物载体的研究提供参考。 相似文献
2.
Effects of ultrasound on the physicochemical properties and microstructure of salted‐dried grass carp (Ctenopharyngodon idella)
下载免费PDF全文
![点击此处可从《Journal of food process engineering》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Teng Wang Zhengxiang Ning Xuping Wang Yehui Zhang Yousheng Zhang 《Journal of food process engineering》2018,41(1)
Ultrasound treatment was used for accelerating drying process and shortening drying time of salted‐dried grass carp, in parallel with evaluation of physicochemical properties and microstructure. The grass carp blocks were salted with ultrasound‐assisted treatment at 0–480 W, 40 kHz for 120 min, then put into heat pump dryer for drying at 50% humidity, 30 °C for 50 hr. The moisture content results showed that ultrasound treatment could significantly promote water loss rate. As the ultrasound power increased, the hardness, the relative content of monounsaturated fatty acid and polyunsaturated fatty acid and total content of free amino acid decreased while the saturated fatty acid and sensory scores increased, respectively. Furthermore, microstructure of the dried‐salted grass carp was studied using paraffin sections and the scanning electron microscope to understand the change of microstructure. In general, ultrasound‐assisted salting significantly increased drying rate, and improved the quality of salted‐dried grass carp. This study shows the potential application of ultrasound in food drying process.
Practical applications
The ultrasound was applied in order to facilitate the traditional process to produce salted‐dried grass carp. And physicochemical properties and microstructure of salted‐dried fish were measured. The results showed that the application of ultrasound could significantly promote the mass transfer of water and improved the product's appeal for customers. The outcome of this study demonstrated a method for producing better quality dried‐salted fish products with a fast speed in the future and showed a great potential of ultrasound in food drying process. 相似文献3.
4.
5.
为探究宁夏菜心湿态发酵的可行性,该研究通过对宁夏菜心基部茎、顶端茎、叶子以及菜心整体进行乳酸菌接种发酵,解析发酵前后微生物、有机酸、亚硝酸盐、抗氧化能力、生物胺以及挥发性风味物质的变化规律。研究表明,发酵后菜心各部位总有机酸含量升高、亚硝酸盐含量降低、抗氧化能力降低和生物胺含量降低,基部茎、叶子、整颗菜心的挥发性性风味物质种类含量均升高;菜心叶子经发酵后亚硝酸盐含量和生物胺含量分别降解了0.30和22.78 mg/kg,DPPH自由基清除率62.06%,总有机酸含量3 212.70 mg/100 g,挥发性风味物质种类丰富,检出48种化合物,相对含量为123.68 g/g。与其他发酵组相比,叶子发酵组的理化指标和挥发性风味物质含量均处于较优水平。以上研究表明宁夏菜心可作为泡菜发酵的原材料,且较优发酵部位是叶子,该研究为菜心的湿态发酵奠定基础。 相似文献
6.
栀子是一种药食两用的植物资源,栀子黄色素是从栀子果实中分离出的活性成分,属于天然水溶性类胡萝卜素。研究表明,栀子黄色素具有抗氧化、抗肿瘤、抗抑郁、抗炎以及降血糖降血压等多种活性功能。因此,在食品及医药等领域极具开发潜力。但目前有关栀子黄色素药理活性的研究还不够系统,有必要对其进行详细分析与总结。本文简要综述了栀子黄色素的提取及精制方法,如传统溶剂浸提法、超声波提取法、柱层析法和膜分离法等,并在此基础上针对栀子黄色素的药理活性进行了系统的论述,总结了其治疗疾病的机制,以期为栀子黄色素的深入研究与应用提供理论指导。 相似文献
7.
为了探讨桑叶提取物的抑菌活性及其物质基础,采用微量稀释法对桑叶70%乙醇提取物的4个萃取部位进行抑菌活性测试并利用气相色谱-质谱联用技术对抑菌活性强的萃取部位进行了成分分析,结果表明桑叶70%乙醇提取物4个萃取部位中石油醚部位抑菌活性最强,其次为乙酸乙酯部位,正丁醇部位和水部位 气相色谱-质谱检测分析石油醚萃取部位的主要成分及其质量分数为植物醇(24.87%)、环二十八烷(18.00%)、棕榈酸(10.20%)、α-亚麻酸(9.06%)、亚麻酸乙酯(7.92%)、硬脂酸(7.14%),另外还含有少量α-生育酚和β-谷甾醇等活性成分. 相似文献
8.
9.
10.
《Journal of food engineering》2006,72(4):403-407
In this work, the sun drying behaviour of figs was investigated. Drying experiments were conducted for figs (Ficus carica) grown in Iskenderun-Hatay, Turkey. The constant rate period is absent from the drying curve. The drying process took place in the falling rate period. The drying data were fitted to the different mathematical models such as Lewis, Henderson and Pabis, Page, Logarithmic, Two-term, Two-term exponential, Verma et al. and Wang and Singh models. The performance of these models was investigated by comparing the determination of coefficient (R2), reduced chi-square (χ2) and root mean square error (RMSE) between the observed and predicted moisture ratios. The results showed that the Verma et al. model was found to satisfactorily describe the sun drying curve of figs with a R2 of 0.9944, χ2 of 0.000483 and RMSE of 0.062857. 相似文献