Rice ( Oryza sativa )

Rice is one of the most important food cereals. It furnishes a large part of the food of the inhabitants of China and Japan. It is a food rich in starch and poor in protein, and furnishes, therefore, heat and energy, and is well adapted for the nourishment of those engaged in hard labor or who undergo extreme physical exertion. The cultivation of rice is rapidly extending in the United States, especially in Louisiana and Texas. The statistical data relating to the rice crop for 1906 are as follows:

Acreage, 575,014 acres

Production, 17,854,768 bushels

Yield per acre, 31.1 „

Price per bushel, 90.3 cents

Total value, 16,121,298 dollars

The adulteration of rice is confined to coating it with talc, paraffin, and glucose. The object of this treatment is to give a better appearance to the grain and to protect it from the ravages of insects. The use of indigestible substances such as talc and paraffin is scarcely justifiable. The starch granules of rice have distinctive properties which enable them to be readily recognized under the microscope, as shown in Fig. 30.

The rice starch grains are polygonal in form and have sharp angles. The grains vary in size from 2 to 10 microns, though the latter size is seldom reached, the most of the grains being about 6 microns. The hilum is seldom visible. The grains occur in the rice kernels mostly in groups of a considerable number of the individual grains forming starch masses of ovoid or angular form.