Effects of microencapsulation in dairy matrix on the quality characteristics and bioavailability of docosahexaenoic acid astaxanthin.

Abstract

Compared with free astaxanthin (Asta), docosahexaenoic acid astaxanthin monoester (Asta-C22:6) has higher stability and bioavailability. However, Asta-E is still unable to be used in the water system. Hence it is necessary to build a water-soluble delivery system. In this study, Asta-C22:6 microemulsion and microcapsule using whey protein isolate (WPI) and hydroxypropyl-β-cyclodextrin (HPβ-CD) as composite wall material were prepared. They were added to three dairy products (milk powder, yogurt and flavored dairy product). A dairy product rich in Asta-C22:6 with high bioavailability was designed by measuring quality characteristics, sensory evaluation and in vivo experiments. Compared with spray drying, the freeze-drying microcapsule had a higher encapsulation efficiency (72.5%), water content (4%) and better solubility, and Asta-C22:6 microcapsule (1g L-1 ) yogurt had the best quality. The bioavailability of Asta-C22:6 microcapsule yogurt was further evaluated. After a single oral dose in mice, the bioavailability of Asta-C22:6 microcapsule in yogurt was significantly increased (Cmax =0.31 μg mL-1 , AUC0-T =3.20 hμg mL-1 ). We successfully prepared Asta-C22:6 microcapsule yogurt, which improved the stability and bioavailability of Asta. The present research is meaningful for delivering unstable bioactive small molecules based on WPI and HPβ-CD. It provides an experimental basis for the application of Asta-C22:6 and the development of functional dairy products. © 2022 Society of Chemical Industry.