[CH] Capsaicin & Salmonella
Rob Solarion (solarion@1starnet.com)
Tue, 21 Aug 2001 09:37:59 -0600
Source: Virginia Tech < http://www.technews.vt.edu/ >
Date: Posted 8/20/2001
Hot Pepper Oil May Prevent Salmonella In Poultry
BLACKSBURG, Va., Aug. 17, 2001 -- Adding capsaicin, the spicy
component of peppers, to the diet of neonatal broiler chicks appears to
increase their resistance to Salmonella, according to Audrey McElroy,
assistant professor of poultry science at Virginia Tech.
As an undergraduate student, McElroy and her graduate advisor got the idea
of feeding hot pepper oil to chickens while they and a graduate student from
Mexico were eating hamburgers filled with hot sauce and covered with layers
of jalapeno peppers. When they wondered aloud why people like spicy foods
even though they often cause a runny nose, watery eyes, and other ill effects,
the Mexican student said that people in his country believe that hot foods and
spices provide protection from disease.
Their laboratory quickly made the jump from humans to poultry, and
hypothesized that a diet that included some form of hot peppers might
protect broilers and other commercial poultry from intestinal disease.
The research began with purchasing 1,530 commercial meat chicks, dividing
them into three groups, and feeding each group a standard corn and
soybean meal-based diet for 42 days. McElroy fed the plain feed to the first
group, but added five parts per million of pure capsaicin to the feed of the
second group, and 20 parts per million to the third group's feed.
She then administered Salmonella enteritidis to the chicks at 21, 28, and 42
days of age. She found that both the low and the high level of capsaicin
increased resistance to the Salmonella without adversely affecting feed
consumption, weight gain, or the taste of the chicken when cooked.
"What we saw from our initial microscopic evaluation is that the capsaicin
appears to cause a very mild inflammation in the intestines," McElroy says.
One theory she's investigating is the possibility that the presence of the
capsaicin-induced inflammation might make it more difficult for the
Salmonella to bind to the intestinal cells and, from there, to branch out to
invade the blood, liver, and spleen.
"Or," she says, "it may be that the capsaicin acts on the intestine to recruit
immune cells, which then fight off the Salmonella."
Her current research is designed to evaluate any observable effects of
capsaicin directly on Salmonella in laboratory conditions, the effects of
capsaicin on the intestinal environment, and the most economical scheme of
feeding capsaicin to commercial poultry.
McElroy says that Salmonella typically results in little to no observable
illness in chickens, but it is a disease of concern to the industry due to
its ability to cause human illness. In a poultry house, it's spread from
bird to bird or through the feeders and water. From there, it may move into
the processing plant, where it can cross contaminate other birds, however
the industry implements procedures both on the farm and in the processing
plant to
minimize this risk.
"I think there's probably less Salmonella in our poultry today than there
was in
the past, because the industry has taken preventative measures," she says.
"But it would be a real breakthrough if we could find a way to reduce levels
even further, without the use of antibiotics."
The poultry that McElroy has worked with seem to have no objections to the
taste or sting of the capsaicin. She theorizes that chickens and other birds
may have evolved so that their taste receptors adapted to allow them to eat
the colorful pods. "Birds in the wild are very attracted to bright colors, and
they spread the seeds by breaking up the pods," she said.
Rodents, on the other hand, have an aversion to the hot seeds. "Feeding
poultry feed to which capsaicin has been added could be very beneficial in
poultry houses," she says. "Rodents love to get into poultry house, where they
eat the feed, destroy buildings, and spread Salmonella and other diseases. If
the food is unappetizing to them, it might keep them away."
Snyder Seed, a New York-based company, developed a line of wild
birdseed coated with chili pepper oil, which they call Hot Pepper Treat.
"Squirrels and other rodents won't eat the food," McElroy says.
"If we can prove that feeding capsaicin to birds does reduce Salmonella in a
commercial poultry-production situation, it would provide a non-antibiotic way
of reducing food-borne pathogens," she says. "Consumers want an antibiotic-
free product, and this may provide the answer."
McElroy's research is partially funded with a grant from the Virginia
Agricultural Council.