Red palm oil (RPO) is a rich source of bioactive compounds such as carotenoids, tocopherols, and tocotrienols with notable health benefits; however, their vulnerability to oxidation, heat, and light during processing and storage limits their functional application. This study aimed to develop an emulsifier-free, biocompatible Pickering emulsion powder using native and modified starches from tapioca and rice to encapsulate RPO. The powders were evaluated for encapsulation efficiency, antioxidant activity, storage stability, FTIR characteristics, thermal properties, and morphology. Modified rice starch-based Pickering emulsion yielded the highest encapsulation efficiency (27.41%), while native rice starch showed the lowest (17.54%) (p < 0.05). FTIR analysis confirmed successful encapsulation through functional group identification. DSC indicated a higher thermal stability in native starch-based powders, while scanning electron microscopy confirmed RPO entrapment in microcapsules. The microcapsule powder of Pickering emulsion stabilized with modified tapioca starch and stored at room temperature (27–29 °C) showed the lowest water activity, minimal lipid oxidation, and the highest retention of carotenoids, α-tocopherol, and total phenolic contents (p < 0.05), along with superior DPPH• and ABTS•+ scavenging activities. Therefore, modified tapioca starch offers a promising, clean-label delivery system for protecting RPO’s bioactive compounds in functional food applications without the need for added emulsifiers.
Mateen et al. (Wed,) studied this question.