Microencapsulation of walnut oil by spray drying: Effects of wall material and drying conditions on physicochemical properties of microcapsules
Microencapsulation of walnut oil by spray drying: Effects of wall material and drying conditions on physicochemical properties of microcapsules
复制标题
DOI：
10.1016/j.ifset.2016.11.011
复制
发表时间：
2017-02-01
影响因子：
6.6
通讯作者：
Kharaghani, Abdolreza
中科院分区：
文献类型：
--
作者：
Shamaei, Samira;Seiiedlou, Seyed Sadegh;Kharaghani, Abdolreza
研究了壁材配方和喷雾干燥条件对核桃油微胶囊理化性质的影响。采用脱脂奶粉（SMP）、SMP + Tween 80和SMP +麦芽糊精三种不同的壁材制备乳剂。对制备的乳剂进行了液滴大小和稳定性分析。在不同的进口干燥空气温度和进料雾化压力下，在双流体喷嘴的中试喷雾干燥机中对乳状液进行干燥，以确定微胶囊化效率最大化的最佳干燥条件。实验还测量了微胶囊的微胶囊化效率、粒径分布、球形度、含水量、容重和形貌。此外，从每种壁材中获得的微胶囊在室温下储存60天后，采用电子能谱化学分析（ESCA）对油的表面覆盖度进行测试。在干燥空气温度为180℃，进料雾化压力为3 bar时，以SMP和Tween 80组合为壁材制备的乳液微胶囊化效率最高，达到91.01%。SMP和Tween 80复合覆盖的微胶囊油的表面覆盖率最低。扫描电镜（SEM）观察显示，在最佳干燥条件下，SMP和Tween 80复合制备的微胶囊表面几乎没有裂纹或裂纹。工业相关性：核桃油含有非常有价值的成分，如必需脂肪酸、生育酚和植物甾醇。然而，在加工食品中直接应用这种功能性油是有问题的，因为它的溶解度低，易氧化。这些问题可以通过使用微胶囊技术大大克服。目前，该技术因其在保护成分功能方面的独特特点，在食品和制药行业受到越来越多的关注。喷雾干燥技术是实现这一目标最常用的技术之一。然而，为了提高成品粉体的理化性能，需要进行全面的研究，以确定合适的喷雾干燥系统的操作条件。(C) 2016年Elsevier Ltd.出版
In this study, the effects of wall material formula and spray drying conditions on physicochemical properties of walnut oil microcapsules were investigated. Three different wall materials including skim milk powder (SMP), SMP + Tween 80, and SMP + maltodextrin were used for emulsion preparation. The prepared emulsions were analyzed for droplet size and stability. The emulsions were then dried in a pilot-scale spray dryer equipped with a two-fluid nozzle at different inlet drying air temperatures and feed atomization pressures in order to determine the optimal drying conditions for maximizing the microencapsulation efficiency. The microencapsulation efficiency, particle size distribution, sphericity, moisture content, bulk density, and morphology of produced microcapsules were also measured experimentally. In addition, the microcapsules with the highest microencapsulation efficiency obtained from each wall material were subjected to surface coverage of oil test using electron spectroscopy for chemical analysis (ESCA) after 60 days of storage at room temperature. The emulsion prepared using SMP and Tween 80 combination as wall material resulted in the highest microencapsulation efficiency (91.01%) at drying air temperature of 180 degrees C and feed atomization pressure of 3 bar. The lowest surface coverage of oil was also observed for microcapsules covered by SMP and Tween 80 combination. Scanning electron microscopy (SEM) observations showed almost no cracks or fissures on the surface of microcapsules produced using SMP and Tween 80 combination at the optimal drying condition.Industrial relevance: Walnut oil contains highly valuable constituents such as essential fatty acids, tocopherols, and phytosterols. However, a direct application of this functional oil in processed foods is problematic due to its low solubility and susceptibility to oxidation. These issues could be greatly overcome by using microencapsulation technology. Nowadays, this technology has received an increasing attention in food and pharmaceutical industries due to its unique features in protecting the functionality of ingredients. Spray drying technology is one of the most frequently used techniques for this aim. However, comprehensive studies need to be carried out in order to determine suitable operational conditions of spray drying system for improving physicochemical properties of finished powder. (C) 2016 Published by Elsevier Ltd.