Refrigerated Trucks and Railway Cars
Refrigerated trucks and railroad cars have had a great impact on the economy and eating habits of Americans. As the United States became more urbanized, the demand for fresh food shipped over long distances increased. Meat products were especially in demand.
In the mid-1800s, cattle raised in Texas were shipped by rail to Chicago, Illinois. Although it was more efficient to slaughter the cattle in Chicago and ship the carcasses to the East, rather than send live cattle east by rail, carcasses could only be shipped during the cold winter months. The first refrigerator car patent was issued in 1867 for a crude design developed by William Davis for meat-packer George Hammond. While Hammond was able to ship meat to Boston by 1872, the cars had to be reloaded with ice once a day, and the meat arrived discolored from contact with the ice.
The first successful refrigerator car was patented in 1877 by Joel Tiffany of Chicago. A similar design was developed the same year by meat packer Gustavus Franklin Swift (1839-1903) and his engineer, Andrew Chase. Ice stored on the car's roof dropped cold air down through the car; warm air was ventilated out through the floor. Once meat could be reliably shipped east, the Chicago slaughterhouse industry boomed, and such meat-packing companies as Swift and Armour made fortunes. Refrigeration with ice is still used in railroad cars as well as in trucks and ships, with powerful fans circulating the cooled air.
An obvious problem with iced refrigeration of transported perishable foods is that the food may spoil if the ice melts before the shipment reaches the market. In the late 1930s, at the request of the Werner Transportation Company, Minneapolis engineer Frederick McKinley Jones (1892-1961) sought ways to build an automatic, ice-free air-cooling unit for long-distance trucking. He designed a compact, shock-proof air conditioner that could withstand the vibrations and jolting of overland travel. Jones's first air conditioning device, which was installed under the truck, failed when it was clogged with mud. A unit mounted in front of the truck, above the cab, was a success.
Jones patented his truck air conditioner in 1940. The system was later adapted for use on railroad cars and ships. Jones's invention changed the food industry. For the first time, perishable foods could be reliably transported over long distances at any time of the year. In turn, food production facilities could be located anywhere; foods could be marketed anywhere. A much greater variety of fresh and frozen foods was now available to millions of people.
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