明胶—壳聚糖微胶囊化过程的研究

本文研究了以维生素E为囊芯的明胶-壳聚糖微胶囊化过程,考察了一些工艺参数(冷凝时间、冷凝温度、交联时间、交联剂用量、芯材比等)对微胶囊产率、维生素E包覆率、维生素E含量、微胶囊平均粒径及分布的影响,同时还研究了微胶囊释放方式,以及改性明胶在微胶囊制备中的应用。     

明胶接技丙烯酰胺的微胶囊化研究

探讨了利用丙烯酰胺改性明胶,以单凝聚法制备微胶囊的可行性,考察了改性明胶分子量及其分布、冷凝时间对微胶囊化的影响,以及交联程度对微胶囊释放的影响规律。     

明胶微胶囊化技术研究

微胶囊化技术作为一门新兴技术在各个领域得到了广泛应用,明胶是用作微胶囊壁材的主要材料之一。明胶的性质对微胶囊的制备、应用有重要影响,人们往往侧重于其应用性,缺乏关于不同明胶对微胶囊化过程、对其应用性能的系统研究,因而不同文献中的结果的可比性就比较差,对微胶囊的选材缺乏指导意义。     

温度对明胶溶液凝冻强度和黏度的影响

明胶是一种由不同长度的聚合物链组成的混合物,凝冻强度和黏度是其重要的质量指标。本文研究了加热的温度和保温时间对明胶水溶液凝冻强度和黏度的影响,揭示了其影响规律。结果表明,随着加热温度的提高和保温时间的延长,明胶水溶液的凝冻强度和勃氏黏度分别有不同程度的降低。     

水解明胶对明胶凝冻强度的影响探究

明胶凝冻强度是评价其质量的一个重要指标,影响的因素有很多。本文专就明胶的水解物对明胶凝冻强度的影响进行了研究,考察了明胶水解物的含量对明胶凝冻强度值降低程度。研究证明了明胶水解物对明胶的凝胶强度影响显著。     

小粒径咖啡因微胶囊制备及其缓释研究

本文研究了以明胶为囊材,采用反相乳化法制备咖啡因微胶囊,考察不同的制备条件对微胶囊粒径与微胶囊载药量、包埋率的影响。结果表明,乳化剂用量、水油比例和搅拌速度对微胶囊粒径有较大影响,加入苯甲酸钠能有效地提高微胶囊的载药量,提高明胶浓度可增加咖啡因的包埋率,且所得的微胶囊有一定的缓释性能。     

复凝聚法制备明胶/阿拉伯胶含油微胶囊工艺过程的研究

研究了复凝聚法制备含油微胶囊的工艺过程。以大豆油为囊芯材料,阿拉伯胶与明胶为璧材,研究了溶液pH值,反应温度,反应时间,壁材浓度,搅拌条件等对微胶囊产品质量的影响。发现搅拌速度对微胶囊的粒径大小和分布影响很大。最佳工艺条件为:明胶与阿拉伯胶质量比为1,浓度都为2%,pH值为4.0~4.5,搅拌速度为1500 r/min,反应温度为55℃,凝聚时间为15~20min,固化温度为10℃,固化时间60 min。     

明胶凝冻强度测试结果分析

明胶凝冻强度的测试结果直接影响到明胶的应用,本文分析了不同道次明胶的凝冻强度测试结果,以及胶面水平对明胶凝冻强度测试结果的影响,且提出了可以应用测试过程中负荷与时间的线性关系情况判断胶面水平的新方法,为明胶凝冻强度的准确测定提供了参考。     

丹参酮的微胶囊化

将丹参酮溶解于肉豆蔻酸异丙酯后，采用明胶／阿拉伯胶为壁材，使用复合凝聚法对其进行了微胶囊化，研究了多种反应条件对丹参酮／肉豆蔻酸异丙酯微胶囊化的影响。结果发现，壁材和芯材的组成比例对微胶囊的包埋率有较大的影响；搅拌速度的增加会使微胶囊的粒度变小；表面活性剂的加入会使微胶囊的粒度分布变窄。在合适的条件下，制备得到的微胶囊产品包埋率可达80％以上，平均体积粒度可达几十微米。     

凝冻时间测定方法及其影响因素

<正> 一、前言现代挤压涂布都向高速、薄层、多层一次涂布的方向发展。乳剂经挤压嘴出来后迅速拉薄,即进入冷凝和干燥工序,此工序是涂布的重要工艺阶段。由于在现代高科技的挤压涂布中仍以明胶这样一种天然胶原蛋白为胶体介质,所以从产量、质量及经济效益等诸多因索考虑出发,在胶片干燥工艺控制过程中,必须考虑到冻点、凝冻时间、干燥点和干燥时间这四个重要的物理参数。这四个重要物理参数反映了明胶介质在不同干燥阶段的不同物理状态的变化。冻点及凝冻时间反映了明胶在冷冻定型阶段由溶液状态向     

Microencapsulation of extra‐virgin olive oil by spray‐drying: Influence of wall material and olive quality

Encapsulation is a process by which small particles of core products are packaged within a wall material to form microcapsules. One common technique to produce encapsulated products is spray‐drying which involves the conversion of liquid oils in the form of an emulsion into dry powders. Emulsification conditions, wall components, and spray‐drying parameters have been optimized for the microencapsulation of different extra‐virgin olive oils. To achieve this goal, the influences of emulsion conditions have been evaluated for different wall components such as proteins (sodium caseinate and gelatin), hydrocolloids (Arabic gum), and hydrolyzed starches (starch, lactose, and maltodextrin). In addition, for each of the tested conditions the ratio of wall solid‐to‐oil and spray‐drying parameters were as well optimized. The microencapsulation effectiveness was determined based on process yield and the ratio between free and encapsulated oil (microencapsulation efficiency). Highest encapsulation yields were achieved when gelatin, Arabic gum and maltodextrin and sodium caseinate and maltodextrin were used as encapsulation agents and the ratio of wall solid‐to‐oil was 1:4 and 1:2, respectively. Under these conditions, 53% of oil was encapsulated. The influence of olive oil quality in the microencapsulation process was evaluated in terms of fatty acids profile alteration after the microencapsulation process.     

Astaxanthin from Haematococcus pluvialis Microencapsulated by Spray Drying: Characterization and Antioxidant Activity

Astaxanthin (AX) is an unstable functional food ingredient. A stable AX powder was developed and its characteristics (such as moisture content, bulk density, solubility, repose angle, and morphology) and antioxidant activity were evaluated. The microencapsulated AX powder was produced by spray drying using maltodextrin (MD)–gelatin and the parameters were optimized by response surface methodology. The results revealed that an optimal microencapsulation process has a ratio of MD to gelatin of 2.1:1, a ratio of wall to core materials of 5.9:1, and a ratio of glycerol monostearate to sucrose fatty-acid ester of 1.1:1. The AX encapsulation yield and encapsulation efficiency were 38.02% and 71.76%, respectively. AX microcapsules had a lower moisture content and bulk density, greater solubility, and good flowability. AX microcapsules showed antioxidant activities greater than Vitamin C, which indicated that the antioxidant activity of AX was not lost. AX microcapsule micrographs showed almost no cracks or fissures on the surface of microcapsules produced by spray drying under the optimal conditions.     

共轭亚油酸微胶囊化中壁材优化的研究

以大豆分离蛋白(SPI)、麦芽糊精(MD)为主要壁材,研究了以喷雾干燥法对共轭亚油酸(CLA)微胶囊化时其复合壁材的优化及其方法。利用界面膜成膜理论分析了各组分配比对微胶囊化效果的影响,进而指导最优条件的选择。结果表明,SPI与MD质量比为1∶4,壁材中玉米糖浆质量分数为38.5%,固形物质量分数在16.7%,CLA添加量以微胶囊质量分数计约为16%时,微胶囊化产率(MEY)和效率(MEE)分别达到了98%和85%;加入明胶可进一步提高微胶囊产品的含油量而微胶囊化效果基本不变。     

Performance inhomogeneity of gelatin during gelation process

The structural and performance inhomogeneities of gelatin gel can directly affect its application as a kind of functional material. The structural inhomogeneity of gelatin caused by the uneven and unstable temperature field has been analyzed by the finite element method in our previous work. Further in this paper, the performance inhomogeneity of gelatin which is closely connected with the actual application is numerically analyzed during the gelation process, which includes the inhomogeneities of the optical and mechanical properties of gelatin gels. The time required for reaching the gel point at different spatial grids is exhibited and discussed. The calculated results also show that the equilibrium shear modulus of gelatin is dependent on the thermal history.     

明胶微胶囊化技术研究进展

本文简要地介绍了微胶囊化技术及其分类方法,微胶囊的性质和主要的应用领域。对以明胶为基础的壁材体系、利用单凝聚和复凝聚方法制备微胶囊的过程、检测分析方法和微胶囊的释放机理等作了评述,并且指出了明胶微胶囊技术中尚未解决和需要进一步探讨的问题。     

Microencapsulation of capsanthin by soybean protein isolate‐chitosan coacervation and microcapsule stability evaluation

Although capsanthin possesses excellent coloring performance and healthcare functions, its application in the food industry is limited due to its susceptibility to humidity, heat, and light. The purpose of this research was to microencapsulate capsanthin by soybean protein isolate (SPI)‐chitosan coacervation and evaluate whether the microencapsulation improved the stability of capsanthin against the adverse conditions mentioned above. The results indicated that the optimum conditions for capsanthin microencapsulation were emulsification speed 10,000 rpm, emulsification temperature 45°C, wall concentration 15 g/L and core to wall ratio 1:2 (w/w). Under these conditions, the droplets in the emulsion were even in size distribution without agglomeration and the microencapsulation efficiency and microencapsulation yield reached 90.46% and 86.69%, respectively. Microencapsulation increased the stability of capsanthin against low/medium moisture, heat, and especially light, but was less effective in protecting capsanthin microcapsules in high moisture. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39671.     

Influence of the Oil Phase on the Microencapsulation by Complex Coacervation

The influence of oil type on the process yield, efficiency of encapsulation, particle size and morphological aspects of coacervated microparticles was investigated. Firstly, several factors affecting microencapsulation of oils by complex coacervation were simultaneously examined. The results indicated that the process yield is mainly dependent on the velocity of homogenization, temperature and polymer ratio. Using optimum conditions for producing microparticles [pH 4.0, 14,000 rpm, 50 °C, gelatin:gum arabic (GE:GA) 1:1 and 2.5 % w/v], different core materials were tested: a vegetable oil (almond oil), an oil with higher hydrophilic lipophilic balance (vetiver essential oil) and a highly hydrophobic oil (mineral oil). The oil phase exerted an influence on microparticle formation, disturbing the complexation of polymers and modifying the core distribution within the particles. Some of the polymers were complexed when mineral oil was used, and the highest efficiency of encapsulation (91.8 %) was obtained with vetiver oil, followed by the almond (70.6 %) and mineral (38.0 %) oils. Particles produced with vetiver oil were larger (43.5 μm) than those produced with mineral oil (35.0 μm) and almond oil (19.2 μm), and the increase in the size is due to the encapsulation of many small droplets of emulsion, characterizing these particles as multinucleate ones.     

Preparation and characterization of a novel thermosensitive hydrogel based on chitosan and gelatin blends

In this study, a novel injectable in situ gelling thermosensitive hydrogel system based on chitosan and gelatin blends was designed and investigated. The addition of gelatin provides the correct buffering and other physicochemical conditions including control of hydrophobic interactions and hydrogen bonding, which are necessary to retain chitosan in solution at neutral pH near 4°C and furthermore to allow gel formation upon heating to body temperature. The chitosan/gelatin hydrogels were studied by FTIR, swelling, and rheological analysis. The rheological analysis evidenced the endothermic gelation of chitosan/gelatin solutions, which indicated their gelation temperatures and reflected the effect of gelatin concentration on the thermosensitive properties of gels. The morphology of this system was examined with laser scanning confocal microscopy and scanning electron microscopy. The images indicated that the gels were quite heterogeneous and porous. The investigation of these gels as vehicles for delivering bovine serum albumin as a model drug of protein showed that the system could sustain the release of the protein drug. These results show that chitosan/gelatin solutions can form gels rapidly at body temperature and have promising perspective for their use in local and sustained delivery of protein drug. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

明胶胶凝对明胶化学交联反应的研究

以猪皮胶原为原料,研究了明胶凝胶化的机制以及主要影响因素分析了胶凝过程中化学成分及其含量、反应温度对交联反应的影响,探究胶原明胶化过程微观结构的变化规律,并通过研究物理凝胶、化学凝胶、混合凝胶的方式,观察在凝胶状态化学网络的储能剪切模量与三螺旋构象中明胶残基数量之间的关系,分析了明胶凝胶过程中的光学、力学、交联密度影响等因素,对三种不同的凝胶方式进行总结,从反应动力学、凝胶影响因素等角度分析其三螺旋结构的变化异同。     

复合凝聚法制备辛硫磷微胶囊剂的研究

采用明胶－桃胶为囊材的复合凝聚方法使辛硫磷微胶囊化。研究了多种反应条件对辛硫磷微胶囊化的影响,测定了辛硫磷微胶囊剂的光解稳定性和在水中的控制释放,并进行了辛硫磷微胶囊剂与常规乳油的药效对比试验。