Effect of Seed Orientation, Acid Delinting, Moisture Level, and Sample Type on Cottonseed Fracture Resistance

Abstract

Abstract. Cottonseed damage during processing is a growing concern for cotton ginners and cottonseed oil processors. A test to evaluate the durability of seed samples would be beneficial to breeders and ginners to help reduce problems associated with seed damage. Toward this goal, cottonseed fracture resistance was studied with a tensile tester fitted with an adapter to apply compressive force. Seeds cracked with more compressive force when oriented vertically in the tester than when oriented horizontally. Seeds had a greater fracture resistance when they were drier. Even differences in environmental relative humidity (35% to 65%) were enough to affect the testing, indicating that cottonseed requires conditioning to obtain consistent results. Treating the seed with sulfuric acid to remove surface linters did not affect the seed’s tendency to fracture, but significant differences were discernible among seed samples with different genetic backgrounds and production histories. Because several individual seeds needed to be tested to achieve representative results, the compressive fracture resistance may not be the most convenient tool for determining the potential for seed damage during processing. A better test might be some form of mechanical damaging device (e.g., a shaker or roller mill) that would allow faster analysis of a representative seed sample. Keywords: Cottonseed, Ginning, Seed damage, Seed fracture resistance.