Location: Functional Foods Research Unit
Title: Gelling ability and crystal morphology of sunflower wax in soybean oil Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 17, 2014
Publication Date: May 7, 2014
Citation: Hwang, H., Kim, S., Evans, K.O., Koga, C., Lee, Y. 2014. Gelling ability and crystal morphology of sunflower wax in soybean oil [abstract]. American Oil Chemists' Society. p. 43. Technical Abstract: Plant waxes can effectively form organogels with vegetable oils and these organogels have drawn considerable interests as alternatives to solid fats containing trans fats and saturated fats in margarines and spreads. Among them sunflower wax showed the most pronounced gelling ability. In an attempt to understand this excellent gelling property, the morphology of sunflower wax crystals formed in the organogel has been examined in this study. The organogel formed with 5% sunflower wax in soybean oil at the cooling rate of 2.8-3.0 °C/min was examined with polarized light microscopy, phase contrast microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was found that phase contrast microscopy could give much more detailed information than polarized light microcopy for the shape of crystals. It was concluded that sunflower wax forms extremely thin plate-like crystals. The thickness of these crystals typically ranges from 100 to 250 nm. It was found that the major ingredients in sunflower wax, wax esters, are responsible for the crystal morphology. The crystal morphology significantly depends on the medium while sunflower wax inherently has the tendency to form the plate-like crystals. The strong gelation ability of sunflower wax could be explained by the effectiveness of immobilization of oil with the numerous thin plate-like crystals.