A hard resinous gum, grayish white in color when fresh. Will darken with age to yellow, red and eventually brown. It is normally sold in blocks or pieces as a gum and more frequently as a fine yellow powder. Sometimes sold in crystalline or granulated form. It has a pungent smell of rotting onions or sulfur but will dissipates with cooking. On its own, it is extremely unpleasant like concentrated rotten garlic. However when cooked, it adds an onion-like flavor to the dish.