When was white rice invented?!

Wild rice predates ancient times. The cultivation of wild rices is ancient. White rice requires the "milling" of wild rice. As of the industrial revolution, this was done with machines. But, previously, man milled rice with mortar and pestle or stone mills.

There seems to be academic debate over the antiquity of rice, driven by competing claims that India or China was the first source of rice.

Let me share with you some excerpts from the Cambridge World History of Food.
http://www.cambridge.org/us/books/kiple/…

"The origin of rice was long shrouded by disparate postulates because of the pantropical but disjunct distribution of the 20 wild species across four continents, the variations in characterizing and naming plant specimens, and the traditional feud concerning the relative antiquity of rice in India versus China..."

"Although the differentiation of the progenitors of Oryza species dates back to the early Cretaceous period, the beginning of rice cultivation was viewed by Western scholars as a relatively recent event until extensive excavations were made after the 1950s in China and to a lesser extent in India. Earlier, R. J. Roschevicz (1931) estimated 2800 B.C. as the beginning of rice cultivation in China, whereas the dawn of agriculture in India was attributed to the Harappan civilization, which began about 2500 B.C. (Hutchinson 1976).

Thus far, the oldest evidence from India comes from Koldihwa, U.P., where rice grains were embedded in earthen potsherds and rice husks discovered in ancient cow dung. The age of the Chalcolithic levels was estimated between 6570 and 4530 B.C. (Vishnu-Mittre 1976; Sharma et al. 1980), but the actual age of the rice remains may be as recent as 1500 B.C. (Chang 1987). Another old grain sample came from Mohenjodaro of Pakistan and dates from about 2500 B.C. (Andrus and Mohammed 1958). Rice cultivation probably began in the upper and middle Ganges between 2000 and 1500 B.C. (Candolle 1884; Watabe 1973). It expanded quickly after irrigation works spread from Orissa State to the adjoining areas of Andhra Pradesh and Tamil Nadu in the Iron Age around 300 B.C. (Randhawa 1980).

In Southeast Asia, recent excavations have yielded a number of rice remains dating from 3500 B.C. at Ban Chiang (Thailand); 1400 B.C. at Solana (Philippines); and A.D. 500 at Ban Na Di (Thailand) and at Ulu Leang (Indonesia). Dates between 4000 and 2000 B.C. have been reported from North Vietnam (Dao 1985) but have not yet been authenticated..."

"Harvesting and processing rice is another laborious process. The cutting instruments evolved from knives to sickles to scythe. Community efforts were common in irrigated areas, and such neighborly cooperation can still be seen in China, Indonesia, the Philippines, Thailand, and other countries. Threshing of grains from the panicles had been done in a variety of ways: beating the bundle of cut stalks against a wooden bench or block; trampling by human feet or animal hoofs; beating with a flail; and, more recently, driving the panicles through a spiked drum that is a prototype of the modern grain combine (see Amano 1979: 248—54 for the ancient tools).

Other important postharvest operations are the drying of the grain (mainly by sun drying), winnowing (by natural breeze or a hand-cranked fan inside a drum winnower), dehusking (dehulling), and milling (by pestle and mortar, stone mills, or modern dehulling and milling machines). Grains and milled rice are stored in sacks or in bulk inside bins. In Indonesia and other hilly areas, the long-panicled Javanica rices are tied into bundles prior to storage...."

Going to the cited reference above to trace the history of rice making tools will most likely provide you with a reliable dating for milled white rice.

http://www.cambridge.org/us/books/kiple/…

"And when any will offer a meat offering unto the LORD, his offering shall be of fine flour; and he shall pour oil upon it, and put frankincense thereon" (Leviticus 2:1, etc.) That's a vague idea of how old is the idea of milling a grain extra amounts to obtain a finer end product. Naturally, the orientals being at least as intelligent, would have done the same thing with their grain (rice), to the point of pulverising and fermenting the grain (sake). Rice, as a seed, is merely the kernel inside a husk. Some people like the husk, some don't. Removing it isn't that difficult.

people were refining and processing food long before there were machines to do it for them
likely they separated white rice from the hulls manually.

there are ancient rice mills, which are basically stone blocks that they turned either manually or by animal.

280 AD? No movies, films, cameras invented, yet!