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Rice straw is not highly prized as food for domestic animals on account of its lack of palatability, nor for bedding because of its coarseness. It is valued as manure for rice and other lands; the straw, together with roots and stubble, containing much the larger proportion of the ash ingredients of the plant. The so-called “rice straw” used for making hats and other articles is not rice straw but that of other cereals grown for that purpose. (490) The so-called “rice paper” of the Chinese
is made from the pith of a tree native to the island of Formosa."
526. Preparation for Use. - The paddy or rough rice is prepared for use first by the removal of the husk or hull, and next by the re
moval of the cuticle or bran; Rice, variety Honduras, showing steps in the mill. the bran in this case being
ing process: 1, rough rice, as it comes from analogous to the bran, mid: the threshing machine, known as paddy; 2, same rice after it has been through the sheller. which removes husks or flowering glume and palea; 3, clean rice after it has been through either mortar and pounder or huller to remove have been removed the kercuticle and embryo, and through polisher to give nels are polished in order it a highly finished surface. (After Bond.)
to enhance their glossy appearance. This is believed in no way to improve the nutritive value but rather to decrease it; however, it greatly improves its commercial value. The following is a detailed account of the milling process:
“The processes of milling rice are quite complicated. The paddy is first screened to remove trash and foreign particles. The hulls, or chaff, are removed by rapidly revolving milling stones' set about two-thirds of the length of a rice grain apart. The produce goes over horizontal screens and blowers, which separate the light
1 U. S. Dept. of Agr., Div. of Stat. Misc. Ser. 6, p. 15.
2 The Present Status of Rice Culture in the United States. By S. A. Knapp U. S. Dept. of Agr., Div. of Bot. Bul. 32, pp. 34-35.
chaff and the whole and broken kernels. The grain is now of a mixed yellow and white color. To remove the outer skin the grain is put in huge mortars holding from 4 to 6 bushels each and pounded with pestles weighing 350 to 400 pounds. Strange to say, the heavy weight of the pestle breaks very little grain.
“When sufficiently decorticated, the contents of the mortars, consisting now of flour, fine chaff, and clean rice of a dull, filmy creamy color, are removed to the flour screens, where the flour is sifted out. From thence the rice and fine chaff go to the fine-chaff fan, where the fine chaff is blown outand mixed with the other flour. The rice flour, as we call it, or more properly “rice meal,' as our English neighbors call it, is very valuable as stock feed, being rich in carbohydrates as well as albuminoids.
“ From the fine-chaff fan the rice goes to the cooling bins, rendered necessary by the heavy frictional process through which it has just passed. It is allowed to remain here for eight or nine hours, and then passes to the brush screens, whence the smallest rice and what little flour is left pass down one side and the larger rice down the other.
“ The grain is now clean and ready for the last process-polishing. This is necessary to give the rice its pearly luster, and it makes all the difference imaginable in its appearance. The polishing is effected by friction against the rice of pieces of moose hide or sheepskin tanned and worked to a wonderful degree of softness, loosely tacked around a double cylinder of wood and wire gauze. From the polishers the rice goes to the separating screens, composed of different sizes of gauze, where it is divided into its appropriate grades. It is then barreled and is ready for market.
“In mills more recently erected the foregoing process has been modified by substituting the 'huller' for the mortar and pounder. The huller is a short, cast iron, horizontal tube with interior ribs and a funnel at one end to admit the rice. Within this tube revolves a shaft with ribs. These ribs are so adjusted that the revolution of the shaft creates the friction necessary to remove the cuticle. The rice passes out of the huller at the end opposite the funnel. It resembles externally a large sausage machine. It requires six hullers for each set of burs. The automatic sacker and weigher is used instead of barreling, sacks being preferred for shipping the cleaned rice. Sheepskins are used for polishing.
“ With the above modifications of the milling processes considerable reduction has been made in the cost of the mill. Mills of a daily capacity of 60,000 pounds of cleaned rice can now be constructed at a total cost of $10,000 to $15,000."
Mills are now constructed suited to plantation use which combine all the operations in one machine, receiving the rough rice or paddy as it comes from the thresher and turning out clean rice ready for use. While the polish is not so high as in the more complicated processes, the product answers the requirement of rice eating.
In the preparation of rice for market it is important to have
the grain remain whole, since if broken its commercial value is reduced about one-half. These unbroken kernels are known as head rice. Great variations exist in different varieties and different grades of rice in the proportion of head rice to broken rice, as well as in the total amount of milled rice produced from a given amount of paddy. No accurate figures can be given of the proportion of head rice to broken rice, but the following illustrates what may be obtained from 100 pounds cf a good sample of rough rice: head rice, thirty-seven; slightly broken, nineteen; very broken, six; polish, three; bran, fifteen; bulls and waste, twenty pounds. While as high as fifty per cent or more of head rice may be obtained in some cases, in others none is obtained. The product of American mills is about as follows: clean rice, sixty; polish, four; bran, seventeen; and hulls and waste, nineteen per cent.
527. By-Products.—The by-products of rice consist of hulls, bran and polish. The bran is properly composed of the cuticle (503) and the embryo, with a small mixture of hulls which it is not possible to prevent in the milling process. In practice, a
considerable quantity of hulls is
mixed with the bran. This mixWUN M UUW ture, sometimes containing as high
as seventy per cent of hulls, is usually referred to in commerce
as rice bran, while when the bran Characteristic ribbon-like rows of cells in rice hulls, highly magnified, which is comparatively free from hull it serve to identify the ground hulls when is called rice meal. Both the bran used as an adulterant. (After Street.)
and the polish are also more or less mixed with small particles of broken rice, called grits. Rice hulls are not only of no value as food for domestic animals, but apparently are injurious. They are consumed at the mills as fuel and sold for packing breakable articles and for similar uses. They are also ground and sold as husk meal or star bran. The
i Twelfth Census of the United States, Bul. 201, p. 4.
Louisiana Station recommends a standard for rice bran of not more than ten per cent of hulls to prevent its adulteration with rice hulls. Assuming pure rice bran to contain ten per cent of crude fiber and pure hulls to contain forty per cent, the percentage of adulteration of bran with hulls may be calculated by subtracting ten from the per cent of crude fiber found upon analysis and multiplying by three and one-third. The New Jersey Station calls attention to the characteristic cells of the hull arranged in several convoluted ribbon-like rows as an easy means of identifying ground hulls when mixed with other feed.
The following table gives recent analyses by the Louisiana Station :
Rice bran, which is the chief by-product, is characterized by its high percentage of fat, which through fermentation frequently breaks up into fatty acids and glycerine, thus causing a rancid taste which makes the bran unpalatable to domestic animals. When fresh, however, the bran makes an acceptable food for all classes of domestic animals and it is especially useful for mixing with the more nitrogenous cottonseed meal. Polish has been successfully fed to cattle and pigs, but is more largely used for
I La. Bul. 77, p. 440.
other purposes, as the manufacture of buttons and as a stuffing material in the manufacture of sausage. The Louisiana Station has found the digestibility of commercial rice bran to be similar to that of wheat bran and polish to that of maize meal when fed to steers.
II. PRODUCTION AND MARKETING,
528. Production of Rice in the World.—While it is estimated that rice enters more or less into the dietary of 800 millions of people, or half the people of the world, the production of rice is not known accurately. It is estimated that Asia produces 72,387 million pounds, Europe 1,507 million pounds, and North America 284 million pounds. According to this estimate, which includes the principal rice producing countries, the production of rice is about one-half that of maize or wheat, somewhat less than that of oats, and somewhat more than that of barley. While rice has been estimated to constitute the principal food of at least onethird the human race, it is probable that other foods, such as sorghum seed and the seeds of legumes, enter largely into their dietary.
The countries of Central America produce rice somewhat extensively, Honduras being especially favored, while the countries of northern South America produce rice sparingly. Italy and Spain are the chief rice producing countries of Europe and Egypt of Africa. Rice is produced throughout the warmer parts of Asia, China, Japan and India being especially noted for its production and the high state of its cultivation.
529. Production of Rice in the United States.—Rice is a secondary crop in the United States, occupying, in 1899, about one-five-hundredth of the area in cereals. The production, however, has increased somewhat rapidly during the past decade on account of the development of the prairie regions
1 La. Bul. 77, p. 436.