Grape seed proanthocyanidin-loaded gel-like W/O/W emulsion stabilized by genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates: Fabrication, stability, and in vitro digestion

作者：Huang, Yaocheng; Lin, Jiawei; Tang, Xiangyi; Wang, Zhiming; Yu, Shujuan^*

来源：International Journal of Biological Macromolecules, 2021, 186: 759-769.

DOI：10.1016/j.ijbiomac.2021.07.062

• Grape seed proanthocyanidin
• W/O/W emulsion
• Genipin-crosslinked
• Alkaline soluble polysaccharide
• Whey protein isolate

The present work aims to fabricate the genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates (G-AWC) to stabilize W/O/W emulsions for encapsulation and delivery of grape seed proanthocyanidins (GSP). After crosslinking reaction, the molecular weight was increased and surface hydrophobicity was decreased. Then, the G-AWC and polyglyceml polyricinoleate (PGPR, a lipophilic emulsifier) were employed to prepare a GSP-loaded W/O/W emulsion with the addition of gelatin and sucrose in W-1 phase via a two-step procedure. Creamed emulsion could be fabricated at W-1/O volume fraction (Phi) of 10%-70% and further increased (Phi) to 75% or even up to 90% could obtain gel-like emulsion with notably elastic behaviors. In the W-1/O/W-2 emulsion with (Phi) of 80%, the encapsulation efficiency (EE) of GSP reached up to 95.86%, and decreased by ca. 10% after a week of storage. Moreover, the encapsulated GSP in the emulsion showed a remarkably higher bioaccessibility (40.72%) compared to free GSP (13.11%) in the simulated gastrointestinal digestion. These results indicated that G-AWC-stabilized W/O/W emulsions could be an effective carrier to encapsulate water-soluble bioactive compounds with enhanced stability and bioaccessibility.