ABSTRACT The aim of this work was to evaluate the potential of tannat grape pomace (GP) extracts for their use as novel oleogelators. Commercial natural waxes (paraffin PFW, candelilla CLW, carnauba CRW, sunflower SFW, and beeswax BW) commonly used as structurants were also studied. High oleic sunflower oil (HOSFO) was selected as oil matrix among other refined oils for its outstanding nutritional quality, and thermal and oxidative stability. GP extracts were produced using three different solvent systems: chloroform (Chl), cyclohexane (Cy) and a mixture of hexane/isopropanol 3/2 (HxI) at a 1/5 (wt/v) ratio. Extracts from Chl and Cy exhibited a minimum gelling concentration (or critical concentration C*) of 5%, while HxI extract failed to achieve HOSFO oleogelation when incorporated at that concentration. Differential scanning calorimetry analyses indicated that at C*, the extracts' oleogels showed greater resistance to crystallization than those based on commercial waxes. Polarized light microscopy analyses showed that at C*, GP‐Cy oleogel displayed evenly distributed tiny needle‐like crystals in a compact network, while GP‐Chl exhibited skinny long needle crystals in a very dense structure with some big clusters, which suggested GP‐Cy oleogels might display better oil binding capacity than GP‐Chl gels. Although GP extracts exhibited higher C* than all the other waxes tested, results demonstrated the high feasibility of using grape pomace extracts as alternative oleogelators for edible oils.
Lázaro et al. (Fri,) studied this question.