The present trend in human diets is to decrease the consumption of the saturated palmitic and stearic fatty acids. Sunflower oil, which is fourth in production among edible vegetable oils in the world, typically contains 65 g/kg saturated palmitic and 45 g/kg saturated stearic fatty acids. A reduction of saturated fatty acids in traditional sunflower oil to 60 to 70 g/kg would lead to a healthier edible oil. The objective of this preliminary study was to search the vast genetic diversity available from the wild ancestors of the cultivated sunflower for a potential source of reduced saturated fatty acids. A survey of wild annual Helianthus annuus, the closest relative of the cultivated crop, was undertaken to identify potentially useful populations with low (less than 70 g/kg combined) palmitic and stearic fatty acids. Achenes of eighty-six populations of H. annuus were collected from the central Great Plains of the USA. The average palmitic acid concentration ranged from 39 to 65 g/kg for the populations. Average stearic acid concentrations ranged from 19 to 37 g/kg. Achene oil of one population of wild H. annuus from Holmquist, SD had a palmitic acid level that averaged 39 g/kg while stearic acid averaged 19 g/kg. The combined 58 g/kg palmitic and stearic acids is almost 50% lower than the present level of these fatty acids in sunflower oil. The level of saturated fatty acids observed in the population remained low when plants were grown in the greenhouse under uniform conditions. In the greenhouse, palmitic acid of this population averaged 40 g/kg, while stearic acid averaged 19 g/kg. This would indicate that palmitic and stearic fatty acids have a genetic base with the potential for selection and incorporation into cultivated sunflower to lower the present level of saturated fats in sunflower oil.

Key words: C16:0, C18:0, oil quality, sunflower, triacylglycerols, triglycerides