An initial rinsing of the dry rice removes surface starch and thus a source of added stickiness. Some rices, notably basmatis and Japanese varieties, are either soaked in water or allowed to rest for 20–30 minutes after washing; they thus absorb some water, which will speed the subsequent cooking. Brown and wild rices can be treated similarly.
From the book On Food and Cooking (2nd edition) by Harold McGee. © 2004 Harold McGee.
By permission of Scribner, a division of Simon & Schuster, Inc.