White pepper consists of only the inner seed with the pericarp, removed by soaking and rubbing or by decorticating when dry. To make white pepper, the berry is picked fully ripe. Its outer shrunken skin is rubbed off, exposing the dried, grayish-white pepper inside. White pepper has a milder, more delicate flavor than black pepper, and is useful for adding a peppery flavor to light-colored sauces and soup without adding black color. More expensive white pepper is hotter than black because it contains more piperine, the volatile oil that gives pepper its characteristic flavor. White pepper contains slightly less essential oil than black pepper. It is preferred in Europe, especially France, and is now popular in Japan for sukiyaki. White pepper stimulates the taste buds in such a way that an alert is sent to the stomach to increase hydrochloric acid secretion, thereby improving digestion. Pepper is an excellent source of manganese, a very good source of iron and vitamin K, and a good source of dietary fiber. White pepper has long been recognized as a carminative, (a substance that helps prevent the formation of intestinal gas), a property likely due to its beneficial effect of stimulating hydrochloric acid production. In addition, white pepper has diaphoretic (promotes sweating), and diuretic (promotes urination) properties.