Sesame seed

Sesame is grown primarily for its oil-rich seeds, which come in a variety of colors, from cream-white to charcoal-black. The small sesame seed is used whole in cooking for its rich nutty flavour, and also yields sesame oil. Sesame seeds are sometimes added to breads, including bagels and the tops of hamburger buns. Sesame seeds may be baked into crackers, often in the form of sticks. Sesame seeds are also sprinkled onto some sushi style foods. Whole seeds are found in many salads and baked snacks.

Whether purchasing sesame seeds in bulk or in a packaged container, make sure there is no evidence of moisture. Additionally, since they have a high oil content and can become rancid, smell those in bulk bins to ensure that they smell fresh.

http://www.whfoods.com/genpage.php?tname=foodspice&dbid=84
http://en.wikipedia.org/wiki/Sesame