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Let's get the bad news over with. Although scientists have spent years studying how to
kill E.coli O157:H7 before it reaches consumers, there's no magic bullet.
"I can't tell a farmer a single thing he can do to reduce the occurrence of this agent
in his animals," Tom Besser of the Washington State University College of Veterinary
Medicine told us.
Some seemingly obvious fixes don't work. Regular cleaning of feed bunks and water troughs
achieves only a momentary improvement, and if you wash a cow's hide before removing it,
the wash water spreads contamination. What does help are repeated antibacterial treatments
after hide removal and during later processing, including steam-vacuuming, hot-water
washing, pasteurization, and rinsing with organic acids.
There are several other reasons to hope beef will eventually be cleaner:
*Last summer, the USDA issued new procedures designed to use what powers it has to respond
more effectively when establishments fail Salmonella standards. However, it also postponed
a plan to seek comments about how to deal with suppliers whose beef is contaminated with
E.coli O157:H7.
*Last spring, the USDA approved the use of activated lactoferrin on beef carcasses.
This natural substance not only inhibits the growth of bacteria, it also latches onto them,
making it easier to clean them off a carcass.
*Scientists have had promising results with probiotics, bacteria that displace O157:H7 by taking
its ecological niche. No probiotics have entirely eliminated the germ, but some have
reduced the percentage of infected animals in a herd.
*Several studies have suggested that switching cattle from corn to grass for their final weeks
reduces the presence of bacteria, though scientists are debating the practical significance
of this finding.
Irradiation has been discussed---and argued over---for years as a way of reducing
microbiological contamination in produce and meat. Irradiation kills bacteria within at
least an inch of the meat's surface, but the food never becomes radioactive. Although the CDC
considers the technology safe, it's not a panacea for keeping ground beef germfree. Careful
handling during and after processing is still needed to avoid recontamination.
Irradiated beef has had an uneven ride in the marketplace, having been introduced at
supermarkets, then withdrawn for lack of consumer acceptance. Last summer, the
technology's fortunes took an uptick as a major supermarket chain, Wegmans, and
Dairy Queen restaurants in Minnesota started selling irradiated ground beef.
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