Physical Properties of Beeswax,Sunflower Wax,and Candelilla Wax Mixtures and Oleogels

To be able to tailor and optimize the physical properties of oleogels for various food applications, more information is needed to understand how different gelators interact. Therefore, the objectives of this study were to evaluate the interactions between binary mixtures of beeswax (BW), candelilla wax (CLW), and sunflower wax (SFW) in pure form as well as in 5% wax oleogels made with soybean oil, in terms of their crystallization and melting properties, crystal morphology, solid fat content, and gel firmness. CLW:BW mixtures had eutectic melting properties, and oleogels from these mixtures with 40:60 to 90:10 CLW:BW were firmer compared to oleogels made with one wax. The main components in SFW and BW appeared to cocrystallize or crystallize at the same temperature, but nonlinear changes in melting point and solid fat content profile of oleogels prepared with the mixed waxes indicated that SFW dominated oleogel formation. In addition, oleogels prepared with mixtures of SFW and BW had lower firmness compared to oleogels prepared with one wax, indicating an incompatibility between the two waxes. The main wax components in SFW and CLW never cocrystallized, and low levels of CLW appeared to prevent SFW from forming a crystalline platelet network. This resulted in low firmness of oleogels made from mixtures of 90:10 to 60:40 SFW:CLW compared to oleogels prepared with one wax. However, the firmest oleogels of all mixtures were made from 10:90 SFW:CLW. Changes in gel firmness and melting properties with mixed wax oleogels were likely to be due to changes observed in the crystal size and morphology. In addition, the firmest gels were shown to result from mixtures that were predicted to have >40% hydrocarbon content, and a high hydrocarbon to wax ester ratio, but minor components such as free fatty acids and fatty alcohols may have also influenced firmness.