Unveiling the formation capacity and characterization of pentacyclic triterpene-structured oleogels: Role of the molecular configuration and oil profile

This research explored the impact of molecular structure and oil type on the formation and structural attributes of pentacyclic triterpene-structured oleogels. Characterization revealed that pentacyclic triterpenes have the propensity to self-assemble into nano- or micron-structures within the oil matrix. These nano- or micronstructures aggregated, effectively confining the mobility of the oils and culminating in oleogel formation. The core skeleton structure of the pentacyclic triterpene and oil profiles did not inherently influence the gelling capacity of the oils. However, the presence of hydrogen bond donors and receptors, specifically at the C-3 and C17 positions, such as hydroxyl (-OH) group and carbonyl (-C=O) or carboxyl (-COOH) groups, is essential for gelation. Intriguingly, the gel strength decreased with increasing permittivity, and an increased amount of "bound" or "immobilized" oil and a reduction in "free" oil content were observed. This study not only underscores the potential of pentacyclic triterpenes as a novel class of oleogelators for the preparation of oleogels, but also sheds light on the influence of molecular structure and oil type on oleogel properties.