The potential of waxes to alter the microstructural properties of emulsion-templated oleogels

Abstract

In this research two oleogelation methods, in casu wax-based oleogelation and emulsion-templated oleogelation, were combined. Emulsion-templated oleogels are known to have a high elastic modulus. However, they also exhibit limited structure recovery after applying shear. Oil partially leaking out of the oleogels greatly limits their application potential in food products. Wax-based oleogelation on the other hand, requires high wax concentrations to attain the required level of structuring, causing a waxy mouthfeel upon consumption. Still, contrary to emulsion-templated oleogels, wax-based oleogels do demonstrate high levels of structure recovery after shear.

The goal of this research was to enhance the structure recovery of the emulsion-templated oleogels by gelling the oil within the structured protein network with low concentrations of candelilla wax, preventing a waxy mouthfeel. The microstructure of the emulsions and corresponding oleogels was elucidated with polarized light microscopy and cryo-SEM. The newly developed oleogels were characterized rheologically using oscillatory and shear recovery measurements and by performing temperature sweeps. The addition of waxes in the emulsion-templated oleogels did not significantly influence the gel strength, but did strongly reduce the shear sensitivity of the oleogels, as was determined with shear recovery measurements and confirmed with oil binding tests.

To assess the true potential of these newly developed oleogels, a shortcrust pastry was developed using the emulsion-templated oleogels as an alternative for a vegetable oil-based margarine. Creep-recovery tests on the doughs revealed that the emulsion-templated oleogels had a better structuring capacity compared to the doughs prepared with wax-based oleogels. However, neither of the two oleogel types were capable of attaining a similar level of dough structuring compared to the vegetable oil-based reference margarine.

Practical Applications To assess the true potential of these newly developed oleogels, a shortcrust pastry was developed using the emulsion-templated oleogels as an alternative for a vegetable oil-based margarine. Creep-recovery tests on the doughs revealed that the emulsion-templated oleogels had a better structuring capacity compared to the doughs prepared with wax-based oleogels. However, neither of the two oleogel types were capable of attaining a similar level of dough structuring compared to the vegetable oil-based reference margarine.

In conclusion, combining several oleogelation methods can increases their application potential by exploiting some of the advantages while attenuating some of the disadvantages of both alternative oil structuring techniques.

http://ift.tt/2AYmcTm