ARS | Publication request: Dehulling of Lesquerella Seeds for the Production of Gums and Oil

Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 16, 2010
Publication Date: May 16, 2010
Citation: Evangelista, R.L., Harry O Kuru, R.E. 2010. Dehulling of Lesquerella Seeds for the Production of Gums and Oil [abstract]. Annual Meeting and Expo of the American Oil Chemists' Society. p. 120.

Technical Abstract: Lesquerella (Lesquerella fendleri), an oilseed crop native to the southwestern United States, is being developed as an alternative source of hydroxy fatty acid (HFA). HFA is used in industrial applications such as lubricants, plastics, emulsifiers, and coatings. The seed coat contains a natural gum which is useful as viscosity modifier. The gum had been recovered by aqueous extraction from whole seed, defatted meal and seed coat (hulls). This study evaluated the effectiveness of milling and density-grading as a method of separating the hulls and cotyledons of lesquerella seeds. Seeds were dehulled using an impact mill and fractionated using 22- and 24-mesh screens. Upon density-grading, 20% of the middle fraction (56% of starting material) was recovered as hull-rich fraction with about 90-97% hulls and containing 5.8 to 11% oil. The cotyledon-rich fraction (CRF) had an oil content of 30-34%. The starting whole seed, hand-picked cotyledons and hand-picked hulls had oil contents of 28.0, 52.8, and 4.2%, respectively. The viscosity of aqueous dispersion with 1% gum ranged from 1,265 to 3,150 centipoise (cP), which exceeded the minimum viscosity requirement of 1,000 cP for similar products. The color of the oil extracted from CRF was lighter (13 Gardner) than the oil from whole seed (14.8 Gardner).