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Growing Antibodies in Tobacco Plants
The oft-maligned tobacco industry may find new life if Canadian scientists are successful. A team of researchers headed by environmental biology professor Chris Hall from the University of Guelph in Guelph, Ontario is exploring the tobacco plant’s potential for producing inexpensive antibodies for use in the detection of foodborne and waterborne diseases. Previously such antibodies—used to detect every bug from E. coli O157:H7, to Listeria and Crystosporidium parvum—cost a minimum of $1,000 per gram. Hall hopes to be able to mass-produce them in tobacco crops and lower the price to $10 per gram within the next five-to-10 years. According to Hall, there are numerous advantages to growing “plantibodies:” Plants can produce more antibodies than animals can, the infrastructure for harvesting and handling plants already exists, and no contaminating viruses or organisms occur in plants that could be transmitted to humans. “We hope to be able to extract 10 to 50 kilograms of antibodies from 100 acres of tobacco,” says Hall.

Chickens, Salmonella and Spicy Foods
According to Audrey McElroy, assistant professor of poultry science at Virginia Tech University, adding capsaicin, the spicy component of peppers, to the diet of neonatal broiler chicks appears to increase their resistance to Salmonella. Based upon the Mexican belief that hot foods and spices provide protection from foodborne disease, McElroy added varying amounts of capsaicin to the diets of 1,530 commercial meat chickens, administering Salmonella enteritidis to the chicks at 21, 28, and 42 days of age. McElroy found that chicks who’d had five parts per million of pure capsaicin added to their feed, like those who’d been eating 20 parts per million pure capsaicin, exhibited increased resistance to the Salmonella (without side effects). Neither the feed consumption, weight gain, nor the taste of the chicken when cooked was adversely affected. McElroy theorizes that the presence of the capsaicin-induced inflammation might make it more difficult for the Salmonella to bind to the intestinal cells.

Impovements in Food Packaging
According to research presented at the 222nd national meeting of the American Chemical Society, packaging food with argon instead of nitrogen gas extends shelf life, maintains freshness, and improves overall food quality. The report was presented by Kevin C. Spencer, Ph.D., senior scientific and technical advisor for the British grocery chain Safeway, who maintains taste tests have shown a 25 percent improvement in shelf life and quality of argon-packaged foods such as potato chips, processed meats and lettuce, and that some fresh pizzas have been improved as much as 50 percent. Traditionally, when foods such as potato chips are packaged, the bag’s empty space is filled with nitrogen. Trace amounts of oxygen remain, however, which causes food to oxidize and become stale. Spencer and his team found that replacing nitrogen with argon removed oxygen more efficiently, because argon is denser than nitrogen and fills spaces more completely.

How Clean is Too Clean?
Science writer Stephen Strauss, author of an upcoming book on the problems and implications of living in a food-rich world, was recently cited as telling the annual meeting of the Crop Protection Institute of Canada there is growing evidence that North American hygiene standards are so strict, children are not being exposed to enough germs to create internal immune systems. Strauss cited a study of children in East and West Germany before unification—a time when West Germany had lower levels of pollution and higher hygenic conditions than its Eastern neighbor, yet whose children were more likely to have asthma, allergies and other diseases. Strauss’ conclusion: “It is possible we are making our world and our food too clean.”

In a related story, researchers at the Paediatric Pulmonology and Allergology Department of Children's Hospital in Salzburg, Austria found children who grew up in a farming environment exhibited a significantly reduced risk of developing asthma, hay fever, and atopic sensitisation. In a survey of children in rural areas of Austria, Germany, and Switzerland, researchers found that exposure of children younger than 1 year (compared with those aged 1 to 5 years) to stables and consumption of farm milk was associated with lower frequencies of asthma (1 percent vs 11 percent , hay fever (3 percent vs 13 percent), and atopic sensitisation (12 percent vs 29 percent). Continual long-term exposure to stables until age 5 years was associated with the lowest frequencies of asthma (0.8 percent), hay fever (0.8 percent), and atopic sensitisation (8.2 percent).