After the corn is cleaned, it is soaked or steeped in warm water for a couple of days. In order to prevent its spoiling, a little sulphurous acid is added. When the corn is suffi- ciently swollen, it is ground coarsely so as to break up the kernel without breaking the germ. The germ is so rich in both protein and fat that it is most easily taken care of by itself. All that is necessary to separate it after the grinding is to run the ground mass into separators, when at a certain density of the liquid the germ, light on account of its oil content, floats on top of the water, while the ground hulls and starch settle and are drawn off from the bottom. The next problem is the separation of the starch from the hulls. It is necessary to grind the mass up much more finely than before, then the semi-liquid is passed over sieves of bolting cloth with a 200 mesh, which is shaken mechanically so that the particles of the hull are sifted out, the starch itself passing through. The hulls are separated, re-ground, and re-sifted, and sprayed with water during the process, in order to get out all the starch possible. The starch and CORNSTARCH 137 water that goes through the sieve, however, is still mixed with protein. This liquor, at just the right density, is passed over long tanks with slightly inclined bottoms. As it flows, the starch settles and rolls along the inclined surface, thus washing itself. The water containing the protein is usually mixed with the hulls and the dried product is used for feed for cattle. The separated germ is pressed to extract some of the oil. Corn oil is used as food only to a small extent, but it is used for making soap and in other industrial processes. The germ with the oil partly expressed is mostly exported to Europe as oil-cake, and is used for feeding stock. After all the processes the starch has gone through, it is still crude. It may, at this stage, be used to make corn syrup and glucose, but otherwise it must be still further refined. Too much protein remains in it, so that it is further washed, sometimes with water alone, sometimes with dilute alkali. Often the plant which separates all the direct products of corn also manufactures dextrine as well as corn syrup and glucose. Cornstarch is less difficult to mix with liquids than is flour, because it does not contain the gluten which flour does. When hot water is poured over starch, it gelatinizes the starch with which it comes into contact. The starchy grains form a mass which is impervious to water and so prevents the water reaching all of the starch grains. This can be prevented by mixing some other substance with the starch before pouring on the water, because the other substance separates the grains and gives them room to swell without sticking together. As raw starch is both less digestible and much less palatable than cooked, prevention of lumping is important. In spite of all the purifications cornstarch has undergone in its manufacture it has a characteristic flavor which 138 FOOD STUDY everyone readily recognizes and which must be due to some other substance mixed with the starch. Only after long cooking does this flavor disappear. QUESTIONS 1. Give two reasons why, in making the pudding, the cornstarch is covered during the long cooking ? 2. Why does cornstarch require so much longer cooking than flour?

AI-modernized reading of the original text

After the corn is cleaned, it is soaked or steeped in warm water for a couple of days. In order to prevent its spoiling, a little sulphurous acid is added. When the corn is sufficiently swollen, it is ground coarsely so as to break up the kernel without breaking the germ. The germ is so rich in both protein and fat that it is most easily taken care of by itself. All that is necessary to separate it after the grinding is to run the ground mass into separators, when at a certain density of the liquid the germ, light on account of its oil content, floats on top of the water, while the ground hulls and starch settle and are drawn off from the bottom. The next problem is the separation of the starch from the hulls. It is necessary to grind the mass up much more finely than before, then the semi-liquid is passed over sieves of bolting cloth with a 200 mesh, which is shaken mechanically so that the particles of the hull are sifted out, the starch itself passing through. The hulls are separated, re-ground, and re-sifted, and sprayed with water during the process, in order to get out all the starch possible. The starch and CORNSTARCH 137 water that goes through the sieve, however, is still mixed with protein. This liquor, at just the right density, is passed over long tanks with slightly inclined bottoms. As it flows, the starch settles and rolls along the inclined surface, thus washing itself. The water containing the protein is usually mixed with the hulls and the dried product is used for feed for cattle. The separated germ is pressed to extract some of the oil. Corn oil is used as food only to a small extent, but it is used for making soap and in other industrial processes. The germ with the oil partly expressed is mostly exported to Europe as oil-cake, and is used for feeding stock. After all the processes the starch has gone through, it is still crude. It may, at this stage, be used to make corn syrup and glucose, but otherwise it must be still further refined. Too much protein remains in it, so that it is further washed, sometimes with water alone, sometimes with dilute alkali. Often the plant which separates all the direct products of corn also manufactures dextrine as well as corn syrup and glucose. Cornstarch is less difficult to mix with liquids than is flour, because it does not contain the gluten which flour does. When hot water is poured over starch, it gelatinizes the starch with which it comes into contact. The starchy grains form a mass which is impervious to water and so prevents the water reaching all of the starch grains. This can be prevented by mixing some other substance with the starch before pouring on the water, because the other substance separates the grains and gives them room to swell without sticking together. As raw starch is both less digestible and much less palatable than cooked, prevention of lumping is important. In spite of all the purifications cornstarch has undergone in its manufacture it has a characteristic flavor which everyone readily recognizes and which must be due to some other substance mixed with the starch. Only after long cooking does this flavor disappear. 1. Give two reasons why, in making the pudding, the cornstarch is covered during the long cooking ? 2. Why does cornstarch require so much longer cooking than flour?

Food study