Development of low-allergenicity algal oil microcapsules with high encapsulation efficiency using extensively hydrolyzed whey protein.

Algal oil is rich in docosahexaenoic acid, which is beneficial for infant development, but its susceptibility to oxidation necessitates microencapsulation. This study investigated the effects of incorporating varying ratios of octenyl succinic anhydride-modified starch (OSA-MS) into a base wall system comprising extensively hydrolyzed whey protein (eWPH) and maltodextrin (MD) to produce algal oil microcapsules with reduced allergenicity and high nutritional value, replacing whey protein isolate (WPI). The residual antigenicity of α-lactalbumin and β-lactoglobulin in eWPH was 3.60 % and 3.88 %, respectively. The addition of OSA-MS significantly enhanced emulsion stability in the eWPH/MD system for algal oil encapsulation. The highest microencapsulation efficiency (98.35 %) was achieved with 21 % OSA-MS, showing no significant difference from that of WPI/MD-based microcapsules. Furthermore, microcapsules prepared with eWPH/MD/OSA-MS (21 %) exhibited smooth surfaces, good dispersibility, and high solubility (91.79 %). These microcapsules also demonstrated superior oxidative stability after 18 days of storage at 60 °C compared to those with other OSA-MS ratios. Overall, incorporating OSA-MS into the eWPH/MD wall system achieved encapsulation performance comparable to WPI/MD, thereby broadening the application potential of eWPH in microencapsulation.