Milled Rice

Whitening is abrasion. The brown rice grain is passed through machines that rub the bran layers away against abrasive surfaces or against other grains, and the degree to which this is carried is a choice — rice may be under-milled, well-milled, or highly milled, and the degree of milling is itself a contract term. Every pass takes weight off the grain and takes some grains apart, which is why the operation is a balance between whiteness and breakage rather than a single fixed process.

Milled rice trades on grain integrity above all. Contracts are commonly written around a stated maximum broken content, and rice is described in the market by that figure — the trade routinely names lots by their broken percentage. Whole grains and broken grains are separated by length graders inside the mill, then recombined to specification or sold apart, which makes broken rice a deliberate, marketed co-product of milling rather than waste.

Beyond brokens, standards measure chalkiness, damaged and discoloured kernels, red-streaked grains, paddy and unhulled grains carried through, foreign material, and the degree of milling itself. Grain length and shape classes and aromatic varietal identity sit alongside the grade as separate descriptors: a lot is bought as a class plus a grade plus, often, a variety, not as a grade alone.

Almost all milled rice is food, cooked as whole grains. The stream separated out during grading — broken rice — has its own established outlets in flour and starch, brewing and distilling, feed, and food use where grain integrity does not matter, and it is modelled here as a co-product of this commodity because it is produced deliberately, graded, and sold. Parboiled rice, in which paddy is soaked, steamed, and dried before milling, is a distinct processing route with different milling behaviour and is not covered on this page.

• Food — the principal traded and consumed form of rice worldwide
• Food and industrial — broken rice into flour, starch, brewing, and distilling
• Feed — brokens and off-specification lots

With the bran and germ gone, milled rice carries little oil and stores well: kept dry, cool, and protected from insects, it holds for extended periods without the rancidity that constrains brown rice. Storage insects remain the real threat, since the grain has no hull and a smooth, edible surface, and infestation in bagged stock is a persistent problem in warm climates. Sealed and hermetic systems are widely used for exactly this reason.

Milled rice moves internationally in bags and in bulk over long distances, and because it is bought partly on appearance, it is handled to avoid the abrasion, breakage, and moisture pickup that would degrade a lot after it has already been graded. Packaging is part of the commodity, not an afterthought.