The use of jojoba oil to formulate oleogels systems using various natural waxes as structuring agents
** Lecture will be given in English**
Abstract:
Oleogels consist of liquid oil structured by an oleogelator, and their gelling behavior depends on the compatibility between the oleogelator’s chemical structure and the physicochemical properties of the oil phase. This study utilized jojoba oil (JO), a liquid wax with a unique unsaturated wax-ester profile that differs from typical triacylglycerol-based edible oils as well as from natural waxes that are solid at room temperature. Three natural saturated waxes with differing wax-ester compositions were used as oleogelators; beeswax (BEW), candelilla wax (CLX), and carnauba wax (CRX). The effects of wax type and concentration on gel formation were examined through thermal, rheological, structural, and textural analyses.
The findings show significant differences in gelation ability, oil-binding capacity, crystal morphology, and hardness among the different wax oleogelators. Minimal gelation concentration of the different waxes in JO followed the trend of CLX<BEW<CRX. BEW samples exhibited needle-like crystals and a small difference between storage and loss moduli, indicating a weak gel. CLX formed a very fine crystal structure, which correlated with its high oil-binding capacity and relatively high hardness values at all concentrations. CRX samples favored crystal growth over nucleation and displayed a wide range of dendritic crystal sizes, resulting in poor oil-binding capacity and a brittle gel. Moreover, CRX concentration did not affect CRX samples’ melting temperature, indicating a low interaction with JO. As expected, increasing wax concentration strengthened the mechanical properties in all formulations. These results suggest that JO is compatible with candelilla wax and beeswax, forming a gel with high stability and moderate mechanical resistance, whereas carnauba wax shows low compatibility with JO and consequently forms poorer gels.
