Many heat-treated commercial food products contain furan, a heterocyclic compound formed by thermal degradation of carbohydrates, amino acids, and polyunsaturated fatty acids. As furan is a potential carcinogen, its presence in food might be harmful.

Pérez-Palacios and colleagues, Universidade do Porto, Portugal, investigated how cooking conditions affect the accumulation of furan and its derivatives, 2-furfural, furfuryl alcohol, 2-pentylfuran, and 5-hydroxymethylfurfural, in breaded fish products. The analysis revealed that furanic compounds are formed in the highest amounts when breaded fish products are deep-fried in olive oil. Conversely, the lowest concentration of furan and its derivatives was observed in products reheated in the microwave after being deep-fried in sunflower oil. The researchers demonstrated also that, when deep-frying in sunflower oil, the generation of furanic compounds can be significantly decreased by choosing a temperature of 160 °C and a frying time of 2 minutes.

The accumulation of furan in deep-fried fish can, thus, be minimized by adjusting the cooking conditions.

• Impact of cooking and handling conditions on furanic compounds in breaded fish products,
  T. Pérez-Palacios, C. Petisca, R. Henriques, I.M.P.L.V.O. Ferreira,
  Food Chem. Toxicol. 2013, 55, 222–228
  DOI: 10.1016/j.fct.2012.12.058.