This study aimed to investigate lipid derived formations of decadien-1-amine, 2-pentylpyridine, and acrylamide in potato chips during frying. 2,4-Decadienal, a lipid derived carbonyl, was monitored in repeatedly used sunflower oil at different thermoxidation levels (0, 6, 12, 18, 24 h at 180 degrees C), and in potato chips prepared in. Formations of decadien-1-amine and 2-pentylpyridine were shown for the first time in potato chips. Frying oil had the highest concentration of 2,4-decadienal after thermal oxidation at 180 degrees C for 6 h. Expectedly, potato chips fried in this oil contained the highest concentration of 2,4-decadienal (29 mg/kg). There was a positive correlation (r(2) = 0.73) between the concentrations of 2,4-decadienal and decadien-1-amine (relative concentration as peak area) formed in potato chips fried in repeatedly used sunflower oil. No 2-pentylpyridine was detected in potato chips fried in unoxidized oil, whereas its concentration ranged between 91 and 154 mu g/kg in potato chips fried in oxidized oil. Acrylamide concentration of potato chips ranged between 525 mu g/kg (fried in oxidized oil, 12 h) and 722 mu g/kg (fried in unoxidized oil). A negative correlation (r(2) = 0.70) was observed between the concentrations of 2,4-decadienal and acrylamide in potato chips. The results suggest that reactions of lipid derived carbonyls should be taken into account to understand better the modifcations of amino acids in fried products.