The influence of linoleic acid content and tocopherol isomeric composition on the frying performance of
high oleic sunflower oil was evaluated during a 14-day restaurant style frying operation. At equal linoleic
acid content, no significant difference was observed between high oleic sunflower oil containing only atocopherol
and the sample containing a mixture of a-, c-, and d-isomers as measured by the amount of
total polar components, oligomers, anisidine value, and free fatty acids. On the contrary, at similar
tocopherol isomeric composition, high oleic sunflower oil containing lower amount of linoleic acid
showed superior frying stability compared to the sample with a higher content of linoleic acid, suggesting
that the frying performance of high oleic sunflower oil is dictated primarily by the level of linoleic acid,
with the tocopherol isomeric composition of the oil having no significant influence. In all oil samples, the
loss of c-tocopherol was higher than the corresponding loss of a-tocopherol.