No abstract

The phase transition behavior and chemical composition of sediments from Canadian and Australian canola oils, as well as from sunflower oil, were studied by differential scanning calorimetry, X‐ray diffraction, polarized‐light microscopy, and chromatographic techniques. Australian canola sediment was similar to Canadian canola sediment in both melting and crystallization behaviors and chemical composition. Compared to canola sediment, sunflower sediment underwent phase transformation (melting and crystallization) at lower temperatures, and the enthalpies associated with the phase changes were greater. The X‐ray diffraction patterns for these materials were similar, indicating identical crystalline structures. Sunflower sediment contained mainly wax esters (99%), while canola sediment contained about 72–74% of waxes. Moreover, sunflower sediment consisted of shorter‐chainlength fatty acids and alcohols than canola sediment. A hexane‐insoluble fraction from Canadian canola hull lipids had fatty acid and alcohol profiles and X‐ray diffraction pattern similar to the corresponding oil sediment.