PORTLAND STAT EUNIVERSITY Frying Beef: Food for Thought Cancer Research at PSU by CliEJohns,~ C urrent research in PSU's Chemistry Department in- dicates that suspected cancer- causing compounds can be formed to some degree by the way we cook many of the foods we eat. Further, this research ~ndicates that, for as yet unexplained reasons. these compounds may be much more prevalent whenever high- temperature cooking methods are used to quickly brown, sear or char beef. In order to investigate this problem, one might expect that researcher Antony J. Vithayathil and Margaret Alic, his assistant, would be wearing chef's hats and using spatulas to cook hamburgers on a smoky restaurant fry-grille. Instead. their third-floor PSU chemistry lab looks quite ordinary to the casual observer. But in the laboratory set- ting of beakers, slides and Bunsen burners, the two researchers find themselves challenging many of the basic assumptions most of us have about food preparation. "Cooking is not really a natural process," says Vithayathil. "I'm not saying that animals don't eat burned food. But as a routine thing, people are the only ones who cook. Whether you do it in the kitchen or in the lab, you're causing some chemical changes (in the food). I'm sure many of them are beneficial. But at the same time, there may be some changes which may have un- necessary side effects." The side effects which the PSU researchers are now studying in- volve the formation in cooking of what are called "mutagenic com- pounds," which are defined as any agents which can cause biological mutation. Mutagenic compounds are strongly suspected of having some of the cancer-causing potential of known carcinogens. Verifying this suspicion forms a cornerstone of the current PSU inquiry. The remainder of the investigation focuses on isolating (a) the molecular structure of the mutagens formed during the cooking process: Antony J. Vithayathil, adjunct research associate in chemistry at PSU, observes as research assistant Margaret Alic makes precise count of mutagenic colonies formed as result of earlier test to see whether such compounds would grow in . solution containing beef extract. (b) their carcinogenic potential in laboratory animals: and (c) the chemical mechanism of their forma- tion. If all that can be discovered, the researchers hope to find easy ways for people to modify cooking procedures, so they eliminate or reduce the formation of these poten- tially hazardous agents in food. The current research at PSU began in late September, 1980, and is being supported for an initial three-year period by the Chiles Foundation of Portland. But Vithayathil's interest in the subject dates back some eight years to Washington University in St. Louis, Mo., where he was co-principal in- vestigator with Dr. Barry Commoner on several research projects in- volving not only food, but en- vironmental samples as well. Com- moner's recent immersion in presidential politics, his appointment to the faculty of Queens College. New York, and Vithayathil's desire to relocate his family to the Northwest. all caused him to resume the research at PSU as an adjunct research associate. What Vithayathil has uncovered so far, while perhaps discouraging enough to consumers, is tantalizing from a researcher's point of view. By using the same preliminary test system (the Ames test) which recent- ly revealed cancer-causing com- pounds in substances formerly used to make children's sleep-wear flame-resistant, Vithayathil's tests of cooked ground beef lead him to declare that, at some dose, "there is a 90 percent probability those com- pounds are going to be carcinogenic in some animal species." At what dose, and in what animals, remain to be seen. But some things already are known. Some compounds similar to these mutagens are formed in browning bread and in vegetarian cooking. But the amounts "are very, very small, compared to what you find in meat," he says. Further, how one cooks meat seems to make a big difference. "In raw hamburger, none of these com- pounds are present. If you cook it 'rare,' it forms a certain amount. If you cook it 'medium,' you get more. And when you cook it 'well-done,' it's a lot more," says Vithayathil. But if the same meat is cooked in a microwave oven. "you practically don't get any mutagens at all." all." The trouble has been pinpointed to the browned or charred surface of the meat, when skillets, cookers, grilles and barbeques are used. Some as yet unknown chemical processes happen during the browning process as the meat begins to sizzle. But in the neafby center of the meat, away from the sizzling, many fewer mutagenic com- pounds are formed. Vlthayathil has discovered. The PSU researchers are now try- ing to prepare these compounds us- ing laboratory methods, so they can be conveniently made in doses large enough to administer to laboratory rats for an extended test period. But for the present, Vithayathil and Alic are content to use a readily-available preparation they have found to be extraordinarily rich in mutagenic compounds - beef extract. Made when ground beef is cooked and boiled down into a dark brown paste with the fat removed, a one-pound container (about the size of two orL dinary cold-cream jars) has the mutagenic compounds present in about 1,000 to 2.000 well-done beef hamburgers, according to Vithayathil. This also is the extract commonly found in certain beefy sauces, frozen dinners and in beef bouillon, he says. Based on what he already has learned. Vithayathil won't touch anything on the supermarket shelf that has the words "beef extract" in the list of ingredients. Further, although he has included beef in his own diet even before he came to the U.S. from India in 1958, he and his contrnued on page 14 Psu's budget ~~ "......page 2 olnl care mrng qrognun page 4 Spring gerdenlq Up6 ...- 5 Alumni Fund I bps gaal pa@ 6 Alumni PuMlc Affdnc CofmMBe
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