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MEATS AND MEAT PRODUCTS
As rated by the Bureau of the Census according to money value of annual product, the industry of slaughtering and meat packing is the largest manufacturing industry of the United States. Many animals are also slaughtered for food on farms and in local butcher shops not classed as manufacturing establishments. The United States Department estimates the farm value of cattle slaughtered yearly at about one billion dollars, and that of swine at somewhat more than a billion dollars; and since it is also estimated that the farm value averages about fifty-three per cent of what the consumer pays, it follows that the retail meat bill of the United States must be between $3,500,000,000 and $4,000,000,000 per year. This is about one third of the total expenditure for food and a larger amount than is spent for food of any other one type.
The meat-packing industry as we now understand it began about fifty years ago, with establishments for the curing and packing of pork at Cincinnati, which was then the center of the corn belt. The close connection between corn growing and swine raising is illustrated by a comparison of Figs. 12 and 13.
With the development of railroad transportation, and the westward extension of the corn belt, the center of the porkpacking industry moved to Chicago; and with the introduction of refrigerator cars, slaughter of beef for transportation in cold storage has grown to a business of great magnitude.
Slaughterhouse methods. The animals are driven up an incline to the upper stories of the packing houses so that after slaughter the carcasses may be run from place to place by gravity. A few beeves at a time are let into the slaughter pen, where each is killed by a blow with a sledge-hammer. The floor of the pen then drops like an elevator, the beeves are rolled out upon the cement floor of the slaughterhouse, and the slaughter pen is raised into position again. The dead animal is at once strung up by the hind feet and, hanging head downward from a wheel on a track which runs from room to room, is bled, dressed, skinned, and the carcass divided in half without the necessity of any lifting or the use of power to transport it.
The animal is bled by cutting the carotid artery, the blood being collected by itself and for the most part dried for fertilizer, though a part of it may find its way into food products. In Europe blood sausage is a common article of food; here it is not generally popular, but a small amount of blood is sold at a large profit in dried or condensed form in patent foods. Commercial albumen may also be made from this blood.
Next the stomach and intestines are removed, the fat which adheres to them serving for the preparation of oleo oil or tallow, their contents going into the cheaper grades of tankage, their muscular walls after thorough cleaning being available for food as " tripe." The lining of the stomach, particularly of calves, may be used as a source of rennet.
Then the hide, horns, and hoofs are removed and worked for oil, gelatin, glue, leather, hair, and horn, the trimmings going into the tankage for fertilizer.
Finally the carcass is split down the backbone and the halves sent to the refrigerating room to be thoroughly chilled.
Although not more than twenty minutes may elapse between the felling of the animal and the arrival of the dressed sides at
the refrigerator, the carcass has been through the hands of a dozen or more men, each one performing some particular operation in a place arranged with special reference to the work to be done, and the convenience of handling the by-product obtained, the carcass being carried from place to place by the slight incline of the track on which its overhead trolley travels.
In beef slaughtering, the " dressed weight " usually approximates 60 per cent of the " live weight."
That part of the beef which is to be sold in a fresh state is cut into quarters which, when properly trimmed and chilled, are loaded into refrigerator cars in which the quarters are hung from the ceiling as in an ordinary cold-storage room; the properly refrigerated car is shipped under seal to the market where the meat is to be retailed. Here it may remain in cold storage for some time longer before being actually sold to the consumer.
There is as yet no general consensus of opinion as to whether a limit should be set to the length of time which meat may be kept in cold storage. That some states set limits to the time of storage of all food was explained in the preceding chapter.
Naturally meat which is frozen will keep with less change than that which is merely cold, and when it is to be kept for a considerable length of time, it should be not simply chilled to the freezing point of water, but actually frozen and kept in a hard-frozen condition.
Cold storage. Richardson and Scherubel, chemists of one of the large packing houses in Chicago, have published1 an extended chemical, histological, and bacteriological investigation of beef kept frozen for over eighteen months.
These investigators find, as had previously been found to be the case in plant tissues, that when the moist protoplasm freezes, the ice forms outside rather than inside the cell so that the microscopic examination of frozen beef shows the muscle fibers shrunken and distorted and separated by layers of ice. Richard
1 Journal of the American Chemical Society, Vol. 30, pages 1515-1564.