Larry
Beuchat rarely eats
raw sprouts. And nothing he has seen in his lab encourages
him to eat more.

“There’s certainly a risk,” said Beuchat, a food
microbiologist with the University
of Georgia College
of Agricultural and Environmental Sciences.

Raw sprouts are popular in salads, sandwiches and other
foods. They’re also cooked as
an ingredient in a number of foods, particularly stir-fried
and sauteed dishes.

The cooked sprouts don’t worry Beuchat. But eating them
raw, he says, poses a risk of
food-borne illness. His research at the UGA Center for Food
Safety and Quality
Enhancement in Griffin, Ga., is at the heart of his
concerns.

“We’ve done quite a lot of work with both the alfalfa
seeds and mature
sprouts,” he said.

The U.S. Food and Drug
Administration has concerns
about raw sprouts as a source of food-borne illness. Several
outbreaks of Salmonella and
E. coli have been connected to raw sprouts.

Beuchat and his graduate students have scrutinized
sprouts throughout conditions
normally used to grow and market them.

They’ve looked for ways to control pathogens, such as
Salmonella and E. coli 0157:H7,
that cause food-borne illness. They’ve tried all kinds of
sanitizers — chlorine, chlorine
dioxide, hydrogen peroxide, diluted ethanol and commercial
products — to ensure
raw-sprout safety.

“We haven’t been successful in killing the organisms to
the degree we’d
like,” Beuchat said. “All of the sanitizers have some effect
on the pathogens,
but none eliminates them.”

The problem with anything short of complete success in
eliminating pathogens from seeds
is the potential for a bacterial explosion as the sprouts
grow.

“If you miss only one or two pathogenic bacteria on the
seeds, they can multiply
to very high numbers,” Beuchat said. “You can have pathogen
numbers of 1 million
to 10 million per gram of sprouts during the three to four
days of production.”

Beuchat has mainly studied alfalfa sprouts, the kind most
commonly used in salads and
sandwiches. Mung bean and soybean sprouts are mostly used
for cooked dishes. The many
other kinds of sprouts include broccoli, clover, onion,
radish and sunflower.

To grow sprouts, seeds are kept constantly wet and at
room temperature (65 to 75
degrees) for three to four days. Those same conditions are
ideal for bacterial growth.

Beuchat said the seeds can become contaminated with a
pathogen anywhere in a long
trail.

“We can’t completely control the environment in the
field,” he said.
“Birds can carry Salmonella. Animals, including deer, can
carry E. coli. Manure that


hasn’t been properly composted can be contaminated.”

Harmful organisms can get onto the seeds after they leave
the field, too.
“Anywhere along the way — in the handling, transportation,
contact with human hands
— the seeds can become contaminated,” he said.

The real problem starts then.

“A pathogen on a dry seed is just there. It’s not
growing,” Beuchat said.
“But once you hydrate it and put it in the sprout production
process, the organism is
going to reproduce during that entire time. It has all it
needs — plenty of moisture,
adequate temperature and nutrients from the sprouts.”

Once the sprouts are mature, they’re washed, packaged and
distributed to stores and
restaurants. They’re often refrigerated during that time,
which limits further bacterial
growth.

But if pathogens were there to start with, the sprouts
will already be unsafe.
“Without heat, we have no effective intervention step to
kill the pathogens,”
Beuchat said.

“Sprouts are nutritious,” said Judy Harrison,
an Extension Service
foods specialist with the UGA College of Family and Consumer
Sciences. “But given
the safety concerns, eating them raw is something to be very
cautious of.”

Children, older people and those with compromised immune
systems are especially at risk
for food-borne illnesses with serious and even life-
threatening complications. “Those
people should probably avoid eating raw sprouts,” Harrison
said.