White pepper consists of the seed of the pepper plant alone, with the darker-colored skin of the pepper fruit removed. This is usually accomplished by a process known as retting, where fully ripe red pepper berries are soaked in water for about a week, during which the flesh of the pepper softens and decomposes. 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. White pepper retains the full pungency of black pepper, but has an altered flavor due to partial loss of aroma compounds. Pepper is extensively used in the wintry cuisine of North India, to impart warmth and pungency to veg. dishes. In the South, it is used as a flavoring spice in non-veg preparations. Pepper is an important spice in the Indian four-spice classic 'garam masala'.