Water-in-oleogel emulsion based on γ-oryzanol and phytosterol mixtures: challenges and its potential use for the delivery of bioactives.

The present work aimed at developing a novel water-in-oleogel emulsion using a mixture of γ-oryzanol and phytosterols as gelator. The gelator network was severely affected by the presence of water, with single β-sitosterol crystals being the main contributors to the self-standing ability of the emulsions. X-ray analyses have shown sharp crystallographic reflections for anhydrous and hemihydrated β-sitosterol crystals, independently of the gelator concentrations and water-in-oleogel ratios. The samples with higher water content have shown additional reflections that could be traced back to monohydrated β-sitosterol crystals, but these were not present after 7 days. The rheological analysis has revealed the impact of the emulsion composition on their strength. Foreseeing their use for the co-delivery of bioactive compounds, we added β-carotene and epigallocatechin gallate to the emulsions. We confirmed their viability toward the incorporation of bioactives in their free-form, constituting a proof of concept for the fortification of lipid-rich foods with both...