Study On Microencapsulation Of Lycopene

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.