An oleogelator extracted from filter sludge of cane sugar manufacture: A comparative study of microstructure, crystallization kinetic and rheological properties

Abstract

Filter sludge, the byproduct of cane sugar manufacturing industry, has potential value owing to its functional components. However, its current applications are limited to fertilizers or forage. This study aimed to enhance the value of filter sludge by extracting sugarcane wax (SW) as an oleogelator through polar solvent thermal treatment. Gas chromatography–mass spectrometry analysis revealed that SW contains six linear higher aliphatic acids that promote triacylglycerol (TAG) alignment and fat crystal formation. Several oleogels were prepared with the addition of beeswax, American candelilla wax, Japanese candelilla wax, sunflower wax, SW, and caraway wax. In comparison, the oleogel structured by SW displayed a relatively stronger crystalline network. The crystals induced by SW displayed small crystal clusters with uniform distribution and density. The difference in morphologies was attributed to the different molecular structures of waxes. Herein, SW was demonstrated as the oleogelator that accelerated the formation of supramolecular network. Subsequently, a rigid crystalline network was constructed with solid characteristics being endowed to the oil phase. These findings provided a feasible strategy for utilizing byproducts of cane sugar manufacturing industry to develop a healthy solid fat applicable as a hydrogenated oil substitute in the food industry.