Parboiled rice is rice that has been partially-boiled in the husk, making it easier to process by hand, improves nutritional profile, and changes its texture. Parboiled rice drives nutrients, especially thiamine, from the bran into the grain, so that it is 80% nutritionally similar to brown rice. The starches in parboiled rice become gelatinized, making it harder and glassier than other rice.
Parboiled rice usually has small amount of milk added to it, to prevent the grain from over hardening. It usually takes more time to cook, and the cooked rice is firmer and less sticky. In North america, parboiled rice is generally partially or fully precooked by the processor.
Parboiled rice http://en.wikipedia.org/wiki/File:Riso_parboiled.jpg Luigi Chiesa
Boil-in-bag package with parboiled rice http://commons.wikimedia.org/wiki/File:Kochbeutel_1.JPG Echtner