
Using Steam Without Cooking, New Device Kills
Bacteria on MeatBy
Doris Stanley October 17, 1997Scientists with USDA's Agricultural Research Service have
designed, built, tested and patented a device that kills bacteria on the
surface of raw meat. Using steam, this simple, inexpensive method quickly kills
Salmonella and other harmful microorganisms on poultry, fresh beef and pork
without cooking the meat. Patented in the United States and Canada (Patent No. 5,281,428),
the new machine could be used easily in meat processing plant lines. In just 25 milliseconds, the new machine kills 99.99 percent of
bacteria by heating the meat surface with steam and cooling it in a vacuum.
Harmful microorganisms usually dwell only on the surface of intact meat. One
problem with using heat to kill the microbes has been that this cooks the
meat's surface, giving it an appearance unacceptable to consumers. ARS engineers Arthur Morgan (retired) and Neil Goldberg at the
Eastern Regional Research Centerin Wyndmoor, PA, developed the new machine. It surrounds a meat carcass with
vacuum to withdraw all air, then flushes it with steam, treats it with a quick
burst of 290 degree F steam, and vacuum cools it. The meat retains its raw
appearance. It has been difficult for industry to remove surface contaminants
from meat because microorganisms escape hot-water washes or bactericide sprays
and surfactants. Liquids can't reach all contaminated surfaces. Feather, hair
or scale follicles are large enough to hide bacteria, but too small to admit a
liquid wash or spray. A commercial version of the machine could treat 4,000 birds an
hour. One machine can serve an entire broiler processing line. Adding the
equipment at the slaughterhouse is expected to add no more than 1 cent per
pound to processing costs. The full story appears in the October Agricultural Research, the
monthly magazine of the Agricultural Research Service. The story is available
on the World Wide Web at: http://www.ars.usda.gov/is/AR/archive/oct97/steam1097.htm Scientific contact: Michael Kozempel, USDA-ARS,
Engineering Science
Unit, Eastern Regional Research
Center, Wyndmoor, Pa., phone (215) 233-6588, fax 233-6795,
[email protected]. U.S. Department of Agriculture | |