Sesame oil is an edible vegetable oil derived from sesame seeds. Besides being used as a cooking oil, it is used as a flavor enhancer in many cuisines, having a distinctive nutty aroma and taste. The oil is one of the earliest-known crop-based oils. Worldwide mass modern production is limited due to the inefficient manual harvesting process required to extract the oil.
Sesame seeds are protected by a capsule which only bursts when the seeds are completely ripe. This is called dehiscence. The dehiscence time tends to vary, so farmers cut plants by hand and place them together in an upright position to continue ripening until all the capsules have opened. The discovery of an indehiscent mutant (analogous to nonshattering domestic grains) by Langham in 1943 began the work towards development of a high-yielding, dehiscence-resistant variety. Although researchers have made significant progress in sesame breeding, harvest losses due to dehiscence continue to limit domestic US production.