Author(s)

Kebing Wang

Corresponding Author

Kebing Wang

Abstract

In this study, the formation laws of harmful chemicals such as benzopyrene, diisobutyl phthalate (DIBP) and nonaldehyde in different edible vegetable oils under high temperature cooking conditions were discussed. Five common edible vegetable oils, soybean oil, rapeseed oil, peanut oil, sunflower oil and corn oil, were heated to different time points (0, 10, 20 and 30 minutes) at three temperature gradients of 160℃, 180℃ and 200℃ respectively, and the samples were analyzed by high performance liquid chromatography and gas chromatography-mass spectrometry. The results showed that the content of benzopyrene was positively correlated with cooking temperature (R²=0.92, P < 0.01), and the content of benzopyrene in peanut oil (18.6μg/kg) exceeded the national standard limit (10μg/kg) at 200℃. The initial content of DIBP may be related to the migration of packaging materials, but high temperature treatment did not significantly increase its content (p>0.05). The production of nonanal increased linearly with temperature and time (R²=0.87). At 200℃, the content of nonanal in peanut oil reached 18.6mg/kg, exceeding the olfactory threshold (5mg/kg), and its production rate was significantly accelerated when the temperature exceeded 195℃. The stability of oil products is related to the content of antioxidant substances and fatty acid unsaturation. Oils with high linoleic acid, such as corn oil and peanut oil, are more likely to generate harmful substances. It is suggested to optimize the oil refining process to reduce the residue of DIBP, and to remind consumers to control the frying temperature and time to reduce the risk of harmful chemicals.

Keywords

benzopyrene; diisobutyl phthalate; nonaldehyde; high temperature cooking; harmful chemicals; edible vegetable oils