Protein thermal denaturation and 12-hydroxystearic acid loading: Dual hydrophobic modification mechanism of the electrospun fiber aerogel-templated oleogels

This study aimed at improving the physical stability of the electrospinning fiber aerogel (EFA) templates and the templated oleogels (EFA-O), and study the effect of hydrophobic treatment on the properties of the templates and oleogels. The protein thermal denaturation and 12-hydroxystearic acid (12-HSA) loading were utilized to hydrophobically modify the electrospun fiber aerogel templates. Both of the two treatments increased the average fiber diameter, and 12-HSA loading made the EFA obtained a stable and lasting hydrophobicity (water contact angle was around 130°). Meanwhile, both hydrophobic treatments improved the stress feedback of EFA, and thermal denaturation could maintain the excellent resilient performance. The oil adsorption and holding capacity of EFA reached 48.77 g/g and 85.73 %, respectively, and the two low-degree hydrophobic methods were combined to prepare compositely treated EFA-O with excellent performances. The hydrophobic EFA framework supported the 3D structure of oleogels, where the fiber diameter could reach 464.01 nm. Thermal denaturation was beneficial to improve the rheological properties, and 12-HSA loading significantly strengthened the texture properties. Hydrophobic treatments could also effectively inhibit the release of free fatty acids (down to 23.84 %) or curcumin (down to 14.19 %) in EFA-O, which was promising for constructing stable controlled-release systems. The combination of the two treatments can achieve complementary modification effects and lead to better physical and chemical properties. This modification method was not only an effective way to strengthen the performances of EFA, but it met the edibility and safety requirements of oleogel preparation.