Frying performance of genetically modified canola oils

The frying performance of low linolenic and high oleic canola oils was comp ared to regular and hydrogenated canola oils. The antifoaming agent dimethy lpolysiloxane (2 ppm) was added to all frying oils. Potato chips were fried in the four oils over a 5-d period for a total of 40 h of frying. Oil samp les were collected each day and analyzed for conjugated dienoic acids, free fatty acids, polymers, oxidation products, and polar components. Polar com ponents were determined by the gravimetric method and by thin-layer chromat ography with flame-ionization detection. The initial quality of the four oi ls was similar except in the amount of tocopherols present. All oils deteri orated after 5 d of frying but differences were not as anticipated, possibl y as a result of observed differences in tocopherol levels.