Refined grains, in contrast to whole grains, refers to grain products consisting of grains or grain flours that have been significantly modified from their natural composition. The modification process generally involves the mechanical removal of bran and germ, either through grinding or selective sifting. Further refining includes mixing, bleaching, and brominating; additionally, thiamin, riboflavin, niacin, and iron are often added back in to nutritionally enrich the product. Because the added nutrients represent a fraction of the nutrients removed, refined grains are considered nutritionally inferior to whole grains. However, for some grains the removal of fiber coupled with fine grinding results in a slightly higher availability of grain energy for use by the body. Furthermore, in the special case of maize, the process of nixtamalization (a chemical form of refinement) yields a considerable improvement in the bioavailability of niacin, thereby preventing pellagra in diets consisting largely of maize products.
| Wheat | Rice | |||||
|---|---|---|---|---|---|---|
| Whole | Refined | Enriched | Whole | Refined | Enriched | |
| Food energy | 100% | 107% | 107% | 100% | 99% | 99% |
| Carbohydrates | 100% | 105% | 105% | 100% | 104% | 104% |
| Fiber | 100% | 22% | 22% | 100% | 37% | 37% |
| Protein | 100% | 75% | 75% | 100% | 90% | 90% |
| Thiamin (B1) | 100% | 27% | 176% | 100% | 17% | 144% |
| Riboflavin (B2) | 100% | 19% | 230% | 100% | 53% | 53% |
| Niacin (B3) | 100% | 20% | 93% | 100% | 31% | 82% |
| Pantothenic Acid (B5) | 100% | 43% | 43% | 100% | 68% | 68% |
| Pyridoxine (B6) | 100% | 13% | 13% | 100% | 32% | 32% |
| Folate (B9) | 100% | 59% | 350% | 100% | 40% | 1155% |
| Vitamin E | 100% | 5% | 5% | 100% | 18% | 18% |
| Calcium | 100% | 44% | 44% | 100% | 100% | 100% |
| Iron | 100% | 30% | 120% | 100% | 54% | 293% |
| Magnesium | 100% | 16% | 16% | 100% | 17% | 17% |
| Phosphorus | 100% | 31% | 31% | 100% | 35% | 35% |
| Potassium | 100% | 26% | 26% | 100% | 52% | 52% |
| Sodium | 100% | 40% | 40% | 100% | 71% | 71% |
| Zinc | 100% | 24% | 24% | 100% | 29% | 29% |
| Copper | 100% | 38% | 38% | 100% | 79% | 79% |
| Manganese | 100% | 18% | 18% | 100% | 29% | 29% |
| Selenium | 100% | 48% | 48% | 100% | 65% | 65% |
Read more about Refined Grains: See Also
Famous quotes containing the words refined and/or grains:
“We are ashamed to seem evasive in the presence of a straightforward man, cowardly in the presence of a brave one, gross in the eyes of a refined one, and so on. We always imagine, and in imagining share, the judgments of the other mind.”
—Charles Horton Cooley (1864–1929)
“Deep with the first dead lies London’s daughter,
Robed in the long friends,
The grains beyond age, the dark veins of her mother,
Secret by the unmourning water
Of the riding Thames.
After the first death, there is no other.”
—Dylan Thomas (1914–1953)