Goma Sesame. Sesamum indicum. ゴマ、胡麻。

Sesame is an annual, flowering plant which is cultivated for its seeds, which grow in pods. Sesame has been long known to mankind as an oilseed: it was first cultivated about 5,000 years ago in Egypt and the Sahara area. It was already know in Japan in the middle or later Jomon-period (2,500-300 BCE) and there are records of its cultivation for lamp oil in the Nara-period (710-784). In the ensuing Heian-period (794-1185) it was also used for medicinal purposes.

Nowadays, 99.9% of all sesame used in Japan is imported. Only a small amount is produced on Kikaijima, one of the Amami Islands belonging to Kagoshima prefecture. The highest production of sesame comes from Burma, India and China.

Sesame has a nutty flavor and is rich in oil. It comes in three forms: white, black and golden (this last one is said to have the best aroma, but is not readily available). White sesame seeds contain more oil than black ones, but black sesame has a somewhat stronger, nuttier flavor.

Sesame seeds are sold in four forms: (1) untoasted, (2) toasted, (3) toasted and roughly ground as well as (4) toasted and ground into a smooth paste.

One can toast sesame seeds oneself by heating a dry frying pan over low to medium heat, then put in the seeds and toast them in 1-2 minutes. Shake the pan occasionally so that all the seeds get heated through. Be careful not to overroast the sesame.

For grinding, in Japan a suribachi is used, a bowl-shaped ceramic mortar which has small grooves on the inside. For the grinding, a wooden pestle (surikogi) is necessary, so that the bowl is not damaged. Grind the seeds until they are flaky and aromatic. Ground sesame is only good fresh, so use it soon after grinding.

[Sesame seeds (goma) with mortar (suribachi) and wooden pestle (surikogi)]

Sesame is used in Japan in the following ways:

• Toasted but not ground (irigoma): black sesame seeds are sprinkled over rice or other dishes to add a color accent (furikake). Sesame seed is also an important ingredient in prepackaged furikake. Both black and white sesame seeds can be used on the outside of uramaki (inside-outside rolls, like the California roll).
• Toasted and ground sesame is called surigoma in Japanese. Used in many recipes in the Japanese cuisine, starting with adding it to shira-ae (cooked vegetables dressed with tofu). As on the picture above, surigoma can also be used in the sauce for tonkatsu.
• Sesame dressing (gomadare) is one of the most popular dressings for salads in Japan and can be found in all supermarkets.
• Sesame paste (nerigoma) is also sold in supermarkets and can be used as a spread on bread, like peanut butter (but much more tasty!). 
• Sesame oil (goma-abura). The best oil for cooking, thanks to its flavor, often blended as it is rather thick. It is indispensable in the oil mixture used for deep-frying tempura.

Sesame is high in proteins and since olden times, various health benefits have been ascribed to it.

"Goma" has also found its way into general culture. As grinding sesame seeds in a suribachi is hard work, the expression "goma-suri" was born to indicate "flattery," especially flattery of one's superior.