Tonka bean oil Tonka bean oil Tonka bean oil is extracted from the seed of "Dipteryx odorata". The oil is composed primarily of coumarin, which is used to flavor tobacco. It is neither a pressed oil, nor an essential oil, but was traditionally obtained by soaking the large, single tonka bean seed in rum or other alcohol for 24 hours, after which crystals of coumarin appear on the outside of the seed, and are then collected. The seeds contain up to 46% oil by dry weight. In recent years, most commercially produced coumarin are synthetic, which has reduced the demand for tonka beans
Sichuan cuisine unusual custom in other parts of the country. The salt produced from Sichuan salt springs and wells, unlike sea salt, does not contain Iodine, which lead to goiter problems before the 20th century. Sichuan cuisine often contains food preserved through pickling, salting and drying. Preserved dishes are generally served as spicy dishes with heavy application of chili oil. The most unique and important spice in Sichuan cuisine is the Sichuan pepper (). Sichuan peppercorn has an intense fragrant, citrus-like flavour and produces a "tingly-numbing" () sensation in the mouth. Other commonly used spices in Sichuan cuisine are garlic, chili peppers,