In this study, oleogels based on safflower oil were produced from beeswax and rice bran wax at different ratios. It was aimed to produce cakes with high level of unsaturated fatty acids by using these oleogels as a shortening replacer. The characterization and oxidative stability of oleogels were investigated. Oil binding capacity (OBC), solid fat content (SFC) and crystallization time (CT) were determined in oleogels. Moisture content, pH, texture and sensory analysis were performed in the cakes. In addition, fatty acid composition, free fatty acidity, peroxide value, conjugated diene-triene and 3-monochloropropane-1,2-diol (3-MCPD) and glycidyl analyzes were performed pre- and post-cooking in oleogels and shortening. SFC increased as gelator concentration increased. Beeswax showed the highest OBC. The shortest CT was determined in rice bran wax. No changes were observed in the fatty acid composition of safflower oil following oleogelation. The change in major fatty acids post-cooking was also not significant. Cakes made with oleogel were acceptable in terms of texture and sensory properties compared to cake produced using shortening. Sensory results showed that some cakes produced with oleogels more acceptable than control. This study revealed that oleogels produced with safflower oil-based beeswax and rice bran wax with high unsaturated fatty acid content can be used in cakes rather than commercial shortening.

The structuration processes of mixed oleogels produced with candelilla wax (CW, 0 or 3%), fully hydrogenated soybean oil (FH, 5-15%), and microcrystalline cellulose (MC, 0-9%) were studied to define their rheological effects. During the cooling CW crystals performed as nucleation sites for FH. The elastic modulus (G’) of oleogels with FH and 3% CW were more than two orders of magnitude higher than those produced with 0% CW. Adding MC to the oleogels increased slightly the G’. Independently of the amount of MC, oleogels structured with increasing amounts of FH and 0% CW showed the elastic properties scaling of colloidal gels. This behavior was lost by adding 3% CW, implying that in mixed FH-CW oleogels, the CW crystal network dominated the oleogel rheology. The flow point and the mechanical reversibility of oleogels and commercial butter (CB) was also determined. CB showed flow points at 44 and 59% strain and mechanical reversibility values of 29 and 35% of G’ measured in a pre-shear step. Adding MC to oleogels structured with FH and 0% CW increased their flow point (37.2%) near those of CB. This effect was not produced in mixed FH-3% CW oleogels. The mechanical recovery of oleogels produced with FH, MC, and 0% CW tend to decrease as the FH content increased. CW and MC did not show a simple concentration–effect relationship for the mechanical recovery. Nonetheless, oleogels structured with 3% CW and 10% FH and 6-9% MC showed mechanical recovery (~60%) close to that of CB.

Due to its unique triacylglycerol composition, palm oil has the particularity of being semi-solid at room temperature. Major fatty acids are palmitic (P) and oleic (O) types, tripalmitin (P3), oleo-dipalmitin (P2O) and palmito-diolein (PO2) being the most abundant tri-saturated, mono-unsaturated and di-unsaturated triacylglycerols. Palm oil is also the most fractionated oil worldwide, mostly in multi-step operations. Dry fractionation is a process that combines crystallization and separation of partially crystallized oil; in the case of palm oil, the main triacylglycerols involved are obviously P3, P2O and PO2. Crude palm oil is made up of symmetrical and asymmetric isomers and, more particularly, contains POP and OPP in a fixed ratio. This ratio may sometimes be modified during the refining process. Adverse effects of excessive OPP content affect the dry fractionation process and are also reflected in the crystallization properties of the produced solid and liquid fractions. It is therefore fundamental to understand at a molecular level the interactions involved. This paper details and compares the binary phase diagrams of several systems: PPP-POP, PPP-OPP; PPP-POO, POP-POO, OPP-POO and POP-OPP, obtained by combining differential scanning calorimetry and variable temperature powder X-ray diffraction. Co-crystallization properties are analyzed in dynamic mode (heating after quenching) and after tempering (few months stabilization at room temperature). The ternary phase diagrams PPP/POP/POO and PPP/OPP/POO give a complementary representation in terms of isothermal melting lines. Better understanding of these molecular interactions is critical for perspicacious carrying out of the palm oil dry fractionation process.