【作者】 孙新虎；

【导师】 丁霄霖；

【作者基本信息】 江南大学 ， 食品科学， 2004， 硕士

【摘要】 本研究采用喷雾干燥法对番茄红素进行微胶囊包埋，以期改善番茄红素的不稳定性和水不分散性。微胶囊化的壁材特征是影响微胶囊特性的至关重要的因素。本文重点对番茄红素微胶囊化的壁材选择、壁材条件优化进行了研究。在确定最佳壁材组成及条件后，对微胶囊化工艺的两个主要工艺：乳化工艺和喷雾干燥工艺进行了条件优化。 在本文的研究中，选择了明胶+蔗糖、阿拉伯胶+麦芽糊精、阿拉伯胶+明胶以及以变性淀粉为主要壁材的四种复合壁材。在对以上四种壁材分别进行条件优化的基础之上，从微胶囊包埋的效率和产率、微胶囊产品的稳定性、微胶囊产品的理化性质、微胶囊产品的显微结构四个方面对壁材进行了筛选。 微胶囊化效率和产率是微胶囊包埋经常使用的衡量指标。研究结果表明，以明胶和蔗糖为壁材的微胶囊包埋，微胶囊效率和产率均比较高，其中微胶囊效率在四种壁材中是最高的。以阿拉伯胶和麦芽糊精为壁材的微胶囊包埋，微胶囊产率非常高，达到97.85％，但微胶囊效率比较低。以明胶和阿拉伯胶为壁材，采用复凝聚法进行微胶囊包埋，效率和产率均比较低。以变性淀粉作为主要壁材的微胶囊包埋，效果与阿拉伯胶和麦芽糊精的结果相似，微胶囊产率比较高，而效率较低。综合比较，以明胶和蔗糖为壁材的微胶囊包埋，微胶囊效率和产率都比较理想，微胶囊包埋效果最好。 储存稳定性是番茄红素微胶囊产品的更为重要的衡量指标。研究结果表明，不同壁材的微胶囊产品中番茄红素的稳定性不同。以明胶和蔗糖为壁材的微胶囊产品稳定性最好。其次为阿拉伯胶和麦芽糊精、明胶和阿拉伯胶，以变性淀粉为壁材的微胶囊产品的稳定性最差。囊外的番茄红素降解速度明显大于囊内的降解速度。研究还发现，壁材不同，对微胶囊产品中产生的异构体的种类影响不大，但对异构化的程度，即反式结构所占的比例有较大影响。综合比较，以明胶和蔗糖为主要壁材的微胶囊产品的稳定性较好。 对上述四种壁材的微胶囊产品进行了水份、密度、粒度、溶解度等理化性质的分析测定。明胶和蔗糖为复合壁材的微胶囊产品水分含量最高，密度和粒度也是最大。而从溶解度特性来看，四种壁材的微胶囊产品均具有良好的水分散性。其中，以变性淀粉的溶解特性最好，其次为阿拉伯胶和麦芽糊精复合壁材、明胶和蔗糖复合壁材，明胶和阿拉伯胶为复合壁材的溶解度稍差。 对四种壁材的微胶囊产品用扫描电镜进行了观察，从得到的照片来看，四种壁材中，以明胶和蔗糖为壁材的微胶囊产品的外观形态最好，大小均匀，囊壁的完好率最高。其他三种产品均存在大量的囊壁破损的现象，尤其是阿拉伯胶和麦芽糊精为壁材的产品，破损率较高。 江南大学硕士学位论文 从上述四个方面的比较，我们认为以明胶十蔗糖的微胶囊包埋效果最好。因此最终选择明胶十蔗糖作为番茄红素微胶囊包埋的壁材。 在确定壁材的基础上，对微胶囊化工艺的乳化条件和喷雾干燥工艺条件进行了优化。结果表明，蔗糖酷13作为乳化剂，得到的微胶囊效率和产率最高。当体系中添加少量的乳化剂，可提高微胶囊效率和产率。当乳化剂用量过高时，产率下降。最佳的乳化剂用量为1%。 在单因素实验的基础上，对喷雾干燥工艺条件进行了实验优化。实验结果表明，微胶囊化的最佳工艺条件为:进料温度60℃、离心式雾化器的转速为15000转/分、进风温度190oC。均质压力为40MPa。更多还原

【Abstract】 In this paper studies were undertaken to get microencapsulated lycopene with storage stability and water dispersibility by means of spray drying technique. With microencapsulation, wall material constitutes a structure which protects the core material from environmental conditions. Various factors that had effects on the microencapsulation of lycopene including of wall materials, formulation of compound wall materials, proportion of core-material and wall material, inlet concentration of emulsion, homogenizing pressure, and temperature of entering wind were systematically studied.The main objective of this work was to determine the influence of wall material composition on Microencapsulation Efficiency (MEE) and Microencapsulation Yield (MEY), and also on the powder characteristics, the stability and microstructure of the products. Four combinations were chosen to be as wall material, including Gelatin + Sucrose, Arabic gum + Maltodextrin, Arabic gum + Gelatin, and modified starch.Results indicated that microencapsulation of lycopene embedded by Gelatin + Sucrose was better than the other three combinations, and MEE was the best. Arabic gum + Maltodextrin could get high value of MEY, while low value of MEE. Arabic gum + Gelatin indicated both low value of MEE and MEY.Some characteristics of microcapsules with different wall materials were investigated, including moisture content, density, powder size and solubility. The microcapsules consisting of Gelatin and Sucrose had the highest moisture content. The density, powder size were also bigger than others. All the products of the four combinations wall materials had good water dispersibility. The products with modified starch as main wall material had the best dissolubility, and then Arabic gum + Maltodextrin, Gelatin + Sucrose, the products with Arabic gum + Gelatin was the worst.The storage stability was one of the important characteristic for the lycopene microencapsule. The results indicated that the microencapsule with different wall materials had different stability, related to the different kind of wall material. The microcapsules consisting of Gelatin and Sucrose showed the best stability, and then Arabic gum + Maltodextrin, Arabic gum + Gelatin, the products with modified starch as main wall material was the worst. It was also found that lycopene outside the wall was more easy to degradation than inside. The experiment also indicated that the different wall material had also effect on the content of isomers, but little effect on the isomer distribution.The microstructure of microencapsules with different wall materials were investigated by means of SEM. The results of observing by SEM indicated that the products of Gelatin andSucrose had a high quality of embedding. The spherical microcapsules were free of surface indentations, and the core material was distributed in the wall matrix in the form of small droplets. No pores or cracks connecting internal parts of microcapsules with the outer surface were detected microscopically. The quality of other wall materials were much worse than this, especially of Arabic gum + Maltodextrin.The above results indicated that microencapsultion of lycopene embedded by Gelatin and Sucrose was better than by others.The quality of microencapsulated products were affected by the microencapsulation technology including emulsification and spray drying technology. Among six kinds of emulsifying agents Sucrose Ether (SE) 13 gave the best results, the best concentration was 1%.The optimum technology conditions of spray drying obtained by experiments were as followed: the inlet temperature of emulsion was 60 C, the speed of centrifugal spray was 15000 rpm. The temperature of entering wind were 190C, the homogenizing pressure was 40 MPa.更多还原