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81.
黄酮类化合物广泛存在于植物界,是许多中草药的有效成分。在自然界中最常见的是黄酮和黄酮醇,此外,还有双氢黄醇、异黄酮、双黄酮、黄烷醇、查尔酮、橙酮及花色苷等。由于类黄酮具有很强的抗氧化和消除自由基的作用,备受国内外研究者的青睐,成为研究的热点。黄酮类化合物有着重要的医用价值,主要体现在:抗炎症、抗过敏;抑制细菌、抑制病毒;防治肝病、防治血管疾病;抗肿瘤、抗化学毒物等。本文从节约资源、提高黄酮得率、实验操作性强等方面分析,选取紫薯茎叶为实验材料,并结合国内外大量研究理论成果,论述了黄酮类化合物的提取方法,将这些方法的优缺点进行了总结,同时,详细的阐述了黄酮类化合物的功能性研究进展,希望对黄酮的研究者起到借鉴、提供参考的价值。  相似文献   
82.
The purpose of this research is to aid manufacturers operating in multiple market segments (characterised by a number of product variants) to formulate and synchronise their product commercialisation strategy. Product commercialisation is primarily characterised by upgrading/launching product features aimed at meeting customer’s preferences, while at the same time, enabling the enterprise to achieve its major commercial objectives. Firstly, by employing the semi-automated crowd sourcing-based approach and considering qualitative customer evaluations, customer-preferred product features have been identified and their relative weights determined. Thereafter, a detailed mixed integer quadratic programming formulation has been evolved taking into account pertinent commercial objectives of the enterprise and engineering-level constraints of the product. The developed formulation has been solved using the Branch and Cut method of commercial solver, LINGO. Detailed sensitivity analysis has been carried out, followed by populating key managerial insights. The proposed framework has been illustrated using a real-life case example of operator cabin used in heavy construction equipment industry. Our focus has been on development and illustration of devised framework; hence, the superiority of results has not been claimed. Better results may be obtained using other heuristics/algorithms.  相似文献   
83.
为了降低零知识的错误概率,通常采用协议的组合操作,独立运行安全的协议,在组合情形,其安全性却并非平凡的。利用UC安全密码元件可以在协议组合过程中作为一个模块安全调用的特性,在UC框架下,通过定义理想功能Fwzk,在Fwzk-混合模型下,讨论零知识协议的组合安全性问题。得到结果:基本Blum协议在序列合成时零知识性具有封闭性。  相似文献   
84.
Native milk fat globule (MFG) size, pH, total fat, protein, and lactose composition in milk from individual cows was examined in autumn and spring 2012 and autumn 2013. Mean MFG diameters ranged between 2.5 and 5.7 µm. Some cows were observed to consistently produce small or large MFG throughout the sampling period, though trends were not consistent across all cows. Small-MFG milk contained more total polar lipids; however, the relative proportion of individual polar lipids did not differ with MFG size, with the exception of phosphatidylcholine, which was greater in small-MFG milk. No significant correlation between MFG size and proximate composition, including calculated fat yield or pH, was found. This work revealed a natural cow-to-cow variation in MFG size exists, which could potentially be exploited to improve the functionality of milk for manufacturing and some products.  相似文献   
85.
二十八烷醇作为一种具有抗疲劳活性的功能性物质,是一种天然存在的长链饱和一元脂肪醇。针对二十八烷醇熔点高及水溶性差的特点,开发了一种水分散型乳化液,并对不同乳化剂、稳定剂及乳化工艺对二十八烷醇乳化液稳定性的影响进行了研究,确定了二十八烷醇乳化液的最佳配方及工艺,并将其添加到运动饮料配方中,研制出一种均匀稳定的抗疲劳功能性运动饮料。  相似文献   
86.
采用乙酸酐对小麦面筋蛋白质进行酰化改性 .结果表明 :小麦面筋蛋白质乙酰化的最佳反应条件为面筋蛋白质质量分数 5 % ,反应温度 35℃ ,乙酰酐用量为小麦面筋蛋白质用量的 15 % ;乙酰化改性后的面筋蛋白质 ,溶解度、乳化能力和起泡能力均得到了提高 ,乙酰化小麦面筋蛋白质对弱筋粉粉质特性的改善效果强于普通谷朊粉 .  相似文献   
87.
The reduced solubility of proteins near the isoelectric pH limits their use in food formulations whose pH lies in the range 5.0–6.0 because of poor functionality. In the present study, the effect of salt on the functionality of native and denatured cashew nut kernel protein isolates at the isoelectric pH was investigated. Both isolates showed improvement in their functional properties, but the improvement was greater for the denatured protein isolate. The solubilities of denatured and native protein isolates at the isoelectric pH increased from 26.4 g l?1 and 64 g l?1, respectively, without salt to maxima of 363 and 308 g l?1, respectively, at 0.75 M salt concentration. The water binding capacity of the isolates increased with increase in NaCl concentration from 1.70 ml g?1 to 1.77, 1.82, 1.92 and 2.2 ml g?1 for denatured protein isolate and from 1.45 ml g?1 to 1.65, 1.69, 1.82 and 1.97 ml g?1 for native protein isolate at 0.25, 0.50, 0.75 and 1.0 M salt concentrations, respectively. When the properties of the isolates in 0.75 M NaCl solutions were compared with those in salt‐free water there were 15% and 116% increases in emulsifying capacity, 40‐fold and 45‐fold increases in emulsifying activity and 4.6‐fold and 40‐fold increases in emulsion stability for native and denatured protein isolates, respectively, whilst the corresponding foaming capacities increased from 4 to 5.5 and 0 to 8.9 ml g?1 protein. Statistically, no difference in the foaming capacity of either of the isolates was observed above 0.5 M NaCl. The foam stability also exhibited similar behaviour. Copyright © 2004 Society of Chemical Industry  相似文献   
88.
Imm JY  Oh EJ  Han KS  Oh S  Park YW  Kim SH 《Journal of dairy science》2003,86(9):2790-2798
Low moisture part-skim Mozzarella cheeses (MC) were manufactured using fresh bovine and caprine milk to study melting, physico-chemical, textural, and microstructural properties of the cheeses during 8 wk of refrigerated storage. Structural changes in cheese matrix were evaluated by scanning electron microscopy and by proteolytic patterns using nitrogen solubility, SDS-PAGE, and Gel-pro analyzer. Meltability of ripened cow and goat MC were not different when fat content of both milks were standardized, whereas bovine MC formed a significantly larger amount of free oil throughout the experiment. The results of the proteolytic patterns, texture attribute (cohesiveness), and microstructure revealed that bovine MC had a greater structural degradation of cheese matrix than caprine MC during the storage. Elevated protein degradation in bovine MC led to more intense brown color formation than the goat counterpart when the cheeses were baked. The melting characteristics showed high positive correlation (r = 0.51 to 0.80) with proteolysis, whereas it was negatively correlated with textural characteristics. Among textural attributes, cohesiveness was highly inversely correlated with melting characteristics (r = -0.69 to -0.88). High negative correlations were also observed between proteolytic parameters and textural attributes (r = -0.48 to -0.81).  相似文献   
89.
功能性西瓜醋酸饮料工艺研究   总被引:6,自引:0,他引:6  
介绍以西瓜为主要原料,经酒精发酵和醋酸发酵成西瓜醋后,再与西瓜 汁,蜂蜜,草莓汁,白糖等调配而成的功能性西瓜醋酸饮料的工艺。  相似文献   
90.
大豆豆渣的研究开发现状与展望   总被引:14,自引:0,他引:14  
利用近期有关豆渣研究与应用的文献,综述了豆渣膳食纤维的功能特性、研究开发现状,分析了豆渣研究 与应用过程中存在的问题,进而对豆渣的应用开发前景进行了展望。  相似文献   
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