Oil-structuring characterization of natural waxes in canola oil oleogels: Rheological, thermal, and oxidative properties

Authors: LIM, JEONGTAEK - Sejong University; Hwang, Hong-Sik; LEE, SUYONG - Sejong University

Submitted to: Applied Biological Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2016
Publication Date: 2/10/2017
Citation: Lim, J., Hwang, H.-S., Lee, S. 2017. Oil-structuring characterization of natural waxes in canola oil oleogels: Rheological, thermal, and oxidative properties. Applied Biological Chemistry. 60:17-22.

Interpretive Summary: Solid fats used in food products such as margarine, shortening, and spreads are high in saturated fats (or sometimes trans fats), which are less healthful than unsaturated fats. Vegetable oils contain a large amount of unsaturated fats and recent studies have shown that these healthy oils can be solidified with an organogelator. Oleogels (or organogels) formed from edible oil and an organogelator can be incorporated in food products as replacements of conventional solid fats containing high contents of saturated fats. Although there have been many organogelators reported, natural waxes such as candelilla wax, carnauba wax and beeswax are of great interest since they are approved as food additives. However, detailed researches on the comparative properties of oleogels formed with these waxes have not been done yet. Furthermore, the oxidative stabilities of these oleogels have not been investigated. In this study physicochemical properties and oxidative stabilities of oleogels prepared with canola oil and three waxes were compared. The database produced in this study provides information on critical quality attributes of oleogels and may facilitate utilization of these materials in healthful food products, in which a large amount of saturated fats is replaced with unsaturated fats.

Technical Abstract: Natural waxes (candelilla wax, carnauba wax, and beeswax) were utilized as canola oil structurants to produce oleogels and their physicochemical properties were evaluated from rheological, thermal, and oxidative points of view. The oleogels with candelilla wax exhibited the highest hardness, followed by carnauba wax and beeswax oleogels while the most adhesive and cohesive properties were observed in the beeswax. The flow behaviors of the oleogels over temperature exhibited the greater sensitivity of carnauba wax oleogels to temperature. The storage moduli of the oleogels were more temperature-dependent, causing the crossover of the storage and loss muduli during the temperature change. Highly linear correlations (R2 > 0.96) were observed in the log plots of solid fat content and rheological property. In addition, the lowest peroxide values were observed in the candelilla wax oleogels, followed by the carnauba wax and beeswax oleogels, demonstrating that oleogels with a harder texture exhibited greater resistance to oxidation during storage.