Tuning Aesthetic and Mechanical Properties of Oleogels via Formulation of Enzyme-Enabled Stereoisomeric Molecular Gelators.

The mechanistic resemblance of oil-based molecular gels (oleogels) to solid fats (trans and saturated) makes molecular gelation an ideal alternative in developing fat-based food and cosmetic products. The recent upsurge in the preference for oleogels (structured oils) is due to them being healthier than conventional solid fats. The present study reveals a simple means of modulating the mechanical and aesthetic properties of oleogels by physically mixing two isomeric low-molecular-weight gelators, mannitol dioctanoate (M8) and sorbitol dioctanoate (S8), which have contrasting oil-structuring behaviors; while M8 formed oleogels with a higher gel strength, the S8 gels were more aesthetic, translucent, and appealing. The gelators were synthesized by enzyme catalysis (a generally regarded as safe protocol). The M8/S8 gels were systematically and thoroughly characterized using a suite of analytical techniques, including minimum gelation concentration, gel melting point, rheological storage modulus, oil binding capacity, light transmittance, and optical microscopy. The results showed that the percentage of light transmittance, which is associated with aesthetics, increased from about 40 to 95% with an increasing fraction of S8 from 0 to 1. Parameters associated with mechanical strength, such as rheology, were also quite responsive to varying proportions of the gelators. The storage modulus (G', a rheological property) increased from about 3300 to about 12 500 Pa with an increasing fraction of M8. As the fraction of M8 increased, the solid fat content (SFC) changed from about 3.51 to 2.08%, while the oil binding capacity changed from about 70.2 to 100.0. This work enables the modulation of the aesthetic and organoleptic properties of a gel via a simple formulation of stereoisomeric molecular gelators.