Stability of pumpkin seed oil

In Austria pumpkins are grown primarily for the production of pumpkin seeds that can be used for eating or the production of salad oil. Pumpkin seed o il is dark green and its fatty acid composition consists typically of linol eic acid and oleic acid as the dominant fatty acids. The saturated fatty ac ids palmitic and stearic acid occur at lower levels. The samples for this s tudy were taken from a breeding program that intends to increase the seed a nd oil productivity. 15 samples with different contents of linoleic acid (4 0-57%) and vitamin E (100-600 mug/g) were selected. The stability of the oi l was measured in a Rancimat that oxidizes the oil at 120 degreesC and meas ures the induction time that is needed for the oxidation. The correlation a nalysis showed that only the ratio of linoleic acid to oleic acid had a sig nificant influence on the oxidative stability of the oil. Vitamin E did not show any correlation. When alpha -tocopherol was added to the oil a strong pro-oxidative effect was observed.