Red palm oil Pickering emulsion with pectin yields improved in vitro beta carotene bioaccessibility and oil stability: Physicochemical characterization and shelf stability studies

Pickering emulsion of red palm oil (RPO) with pectin as stabilizer was optimized using response surface methodology (RSM). RSM parameters for final red palm oil pickering emulsion (RPE) were 3% pectin, 30% RPO, and homogenization speed of 24,000 rpm for 15 min. RPE was subjected to physicochemical characterizations, along with storage studies for 15 days. Microstructure imaging of RPE confirmed pickering emulsion formation. Droplet diameter and zeta potential of RPE were 1.779 μm and −32.5 mV, respectively. Fourier transform infrared spectroscopy of RPE suggested hydrogen bonding interactions between the components, and thermogravimetric analysis revealed stability up to 40°C. Gastrointestinal bioaccessibility of naturally occurring β-carotene in the RPE (37.76 ± 1.2%) was found to be four times higher than that of RPO (8.7 ± 0.8%). The RPE was more stable at 4°C as indicated by storage analyses. RPE can improve the bioaccessibility of nutritionally important bioactive compounds. Practical applications Pickering emulsions of RPO stabilized by pectin can be used for developing functional foods with improved bioaccessibility of lipophilic bioactives such as carotenoids as well as for the delivery of temperature sensitive nutritional and bioactive compounds. These emulsions can also be found applications in beverages, low temperature processed foods and vegan fat substitutes.