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E. G. HAMMOND, Department of Food Science and Human Nutrition, Iowa State University, Food Sciences Building, Ames, IA 50011

Vegetable oils with altered fatty acid compositions have been sought for improved stability to oxidation, crystal properties, and nutritional values. We have produced soybean mutants with altered seed oil fatty acid compositions by treatment with mutagenic agents. Initially the goal was to reduce the linolenate concentration, normally about 8%, to improve flavor stability. This was achieved with mutants that give <2% linolenate. Soybean oil normally contains about 10% palmitate, and lines with 3 to 32% palmitate have been produced. Low palmitate soybean oil is being sold commercially. Elevated palmitate is associated with lower seed oil content. Lines with up to 30% stearate in the seed oil have been produced. High-stearate lines are associated with lower yields and inconsistent germination. Changing the fatty acid composition of soybean oil affects the fatty acid composition of phospholipids and triglyceride distribution. Phospholipids play a physiological role, but relatively great changes in their composition have relatively little effect, on seed germination, membrane integrity or seedling growth rate. The triglyceride composition is affected in complex ways by changes in fatty acid composition, and these changes may affect the stability of the oil and throw light on triglyceride biosynthesis. The marketing of oilseed with altered fatty acid compositions entails a number of added costs for seed production and segregation and analytical verification. Marketing channels currently are designed to treat and process an oilseed as a single commodity. Consumer concern about genetically modified oils and the confusion caused by multiple kinds of an oil raise questions of labeling. These questions are currently being sorted out in the market place.