Oleogelators are molecules that, when combined with edible oils can form semi-solid materials. Although many molecules have been tried as oleogelators in the last 20 years, much is still unknown. Here, the molecular structure of two possible oleogelators: triacontane (TC) and behenyl lignocerate (BL) were studied using a mathematical model for each molecule and carrying out computer simulation using the Metropolis Monte Carlo (MMC) algorithm in which the only interaction is via Lennard-Jones dispersion forces. The computer simulation explored the possibility of having either rigidly-extended molecules or twisted ones via the formation of gauche bonds. The results showed that both TL and BL molecules create a monolayer that did not include any gauche bond so that all molecules were effectively rigidly extended. The effective thickness of the monolayer was compared with experimental data and with the predictions of Peyronel et al. (in review) which assumed that the molecules were rigidly-extended. The work reported here justified that assumption. The conclusion was that the TC and BL molecules must be packed with a tilt angle in relation to the methyl group plane to match the experimental data. The angle of TC tilt was calculated to be ~27° which essentially confirms that reported by Peyronel et al. (in review).

Three oleogeletors molecules (Triacontane (TC), Stearic acid (SA), and Behenyl Lignocerate (BL)) were studied individually, in pairs, or all together to make an oleogel using triolein as the oil. WAXS, SAXS and USAXS were used to elucidate the solid structures from angstroms to a few micrometers. A two-dimensional mapping of atomic positions for each molecule was carried out to understand the crystalline multilayer structures formed. We assumed that the molecules were rigidly extended and that they underwent no significant (hindered) rotations so that the free energy is determined by the Lennard-Jones interactions of closely-packed multilayers. TC molecules were predicted to form a tilt angle of θt ≈ 33°, yielding a SAXS line at q≈ 0.194 Å-1, in acceptable agreement with the measured q=0.181 Å-1.For SA crystals θt ≈ 33° (predicted) yielding a SAXS line at q=0.150 Å-1 compared to q=0.159 Å -1 (observed). No mixed crystals were observed for any pair of molecules or when all three were used. USAXS data showed that SA forms large nanocrystals compared to TC and BL. All three combinations of molecular pairs showed basic scatterers smaller or similar to those of individual molecules. The theory presented here, together with the experimental results, showed why no mixed crystals are formed from two or all three molecules. Data from the USAXS region suggested that, when using all three molecules, a more compact fractal structure was obtained, compared with those if one or two of the molecules were used.

The crystallization behavior of mango kernel fat (MKF) at 25 °C with and without the application of high-intensity ultrasound (HIU) (20 kHz, 125 W) was studied as a function of ultrasound amplitude level (30%, 50% and 70% of the maximum amplitude of 180 μm). The irradiation time was fixed at 5 s. It was found that HIU induced MKF crystallization. The crystallization induction time decreased with a decrease in crystal size and an increase in the number of crystals as the HIU amplitude increased. The β′→β transformation was also accelerated with HIU application. This work has shown that there is a great potential for the use of HIU in the food industry to achieve a shorter and more controllable crystallization process. In particular, HIU could be used as an efficient tool for controlling the polymorphic transition of fats.