Assessment of thermo‐oxidative rancidity in sunflower oil and fried potato chips stabilised with oleoresin sage ( Salvia officinalis L.) and ascorbyl palmitate by altered triglycerides and electronic nose

Summary Oleoresin sage ( Salvia officinalis ) ( SAG ) (200–1500 mg kg −1 ), ascorbyl palmitate ( AP ) (100–300 mg kg −1 ) and TBHQ (200 mg kg −1 ) were assessed for delaying the thermo‐oxidation in sunflower oil ( SO ) during 18 h of frying (180 °C). Electronic nose compared the global aroma fingerprints of potato chips fried in oils. The chemical rancidity indices viz., fatty acids, total polar compounds ( TPC ), altered triglycerides (dimers, polymers, oxidised monomers, diglycerides), free fatty acids, conjugated dienes and induction periods were monitored along with physical indices viz., viscosity and colour. SO SAG + AP (1309.62 + 270.71 mg kg −1 ) outperformed SO TBHQ by preserving polyunsaturated fatty acids (60.48% vs. 56.23%), retarding TPC s (28.16% vs. 29.91%), triglyceride dimers (90.24 vs. 95.82 mg g −1 ) and polymers (25.40 vs. 26.98 mg g −1 ) concomitantly extending the oil disposal time (basis 25% TPC ) (15.9 vs. 14.7 h). The postfrying viscosity, colour values and global aroma fingerprints of fried chips indicate a close match between SO SAG + AP and SO TBHQ .