Fibrils of γ-Oryzanol plus β-Sitosterol in Edible Oil Organogels

Mixtures of gamma-oryzanol and beta-sitosterol are able to form transparent organogels in edible oils. Small-angle X-ray scattering was used to elucidate the microstructure of the building blocks of these organogels in sunflower oil. It was found that the plant sterol(ester)s form hollow tubes with a diameter of 7.2 +/- 0.1 nm. Tubes prepared with gamma-oryzanol-rich structurant show the least bundle aggregation, and can be supercooled during formation most easily. The tubes melt at elevated temperatures, in agreement with the loss of structuring capacity as observed in earlier experiments.