Comparing the features of astaxanthin at different microencapsulated form

學生姓名: 周芷瑩
指導教授: 張克亮
學　　號: 10432022
學期: 105上
摘　　要: Astaxanthin is a type of carotenoids found in marine animals to give them a characteristic red pigmentation. Astaxanthin has been shown to exhibit a stronger antioxidant activity than vitamin E and β-carotene. However, astaxanthin has poor water solubility and the presence of double bonds has made astaxanthin susceptible to oxidants, light and heat; those limit its application in the food industry. Microencapsulation can protect astaxanthin against deterioration and to improve the solubility and stability. The utilization of calcium alginate to encapsulate astaxanthin was able to significantly improve the thermal stability of astaxanthin. Using maltodextrin and gum arabic, separately or mixed, mixed with phosphatidylcholine, to microencapsulate astaxanthin. The resulting powders present interesting properties for use as food ingredients, as they have an intense red color, high water solubility and stability. Furthermore, the higher bioaccessibility of the astaxanthin contained in the extract and the higher antioxidant activity of the bioaccessible fractions, as compared to those of the non-encapsulated sample. Blends of milk protein (either whey protein isolate, WPI or sodium caseinate, SC) and carbohydrate (soluble corn fiber, SCF 70) as the wall materials can provide reasonably good properties of water activity, surface morphology, microencapsulation efficiency and oxidative stability.