Monitoring deep frying performance of Monola and Monosun oils

Five canola oils with different fatty acid profiles and one high oleic sunf lower oil were chemically and physically monitored and chips fried in these oils were sensory evaluated over two 80-hour deep frying trials at 190 deg rees C. High oleic canola oil with low linolenic acid content (2.6%) had hi gh flavour stability and oxidative stability and was the best of the six oi ls; high oleic canola oils with 5.2% and 5.3% linolenic acid gave similar b ut slightly inferior performance. These three oils were better than the hig h oleic sunflower oil and much better than RBD standard canola oil and part ially hydrogenated canola oil. Changes in fatty acid content, total polar c ompounds, dielectric constant, colour index and iodine value were significa ntly correlated with hours of deep frying and could be used to monitor oil. The TPM VERI-FRY(R) PRO Quick Test for total polar compounds and measureme nt of dielectric constant by the Foodoil Sensor were the most convenient an d reliable ways to monitor individual oil quality during deep frying.