Development and Analysis of Bilayer Foamed Oleogels Stabilized with Ecogel™: Exploring the Role of Tween 80 in Modifying Physicochemical Properties

Oleogels are structured materials formed by immobilizing oil within a polymer network. This study aimed to synthesize bilayer foamed oleogels using Ecogel™ as an emulsifier—a natural gelling and emulsifying agent commonly used to stabilize emulsions. Ecogel™is multifunctional, particularly in cosmetic formulations, where it aids in creating lightweight cream gels with a cooling effect. However, the specific goal of this study was to investigate the physicochemical properties of oleogels formed with Ecogel™, Tween 80, gelatin, and glycerin. The combination of these ingredients has not been studied before, particularly in the context of bilayer foamed oleogels. The biphasic nature of the resulting materials was explored, consisting of a uniform lower phase and a foamed upper layer. Several analytical techniques were employed, including FT-IR spectrophotometric analysis, moisture content evaluation, surface wettability measurements, microscopic imaging, and rheological studies, in addition to surface energy determination. The results demonstrated that the addition of Tween 80 significantly improved the stability and rigidity of the oleogels. Furthermore, storage at reduced temperatures after synthesis enhanced the material’s stabilizing properties. These materials also showed an affinity for interacting with non-polar compounds, indicating potential applications in skincare, especially for interaction with skin lipids.