A Kinetic Study of Furan Formation in Wheat Flour-Based Model Systems during Frying.

Abstract

Furan is a possible human carcinogen, which is formed in worldwide highly consumed fried starchy foods. In order to elucidate the mechanisms responsible for its occurrence in this food category and propose techniques for its mitigation, the kinetics of furan formation, oil absorption, lipid oxidation, and color change were studied in wheat flour-based model systems during frying at 160, 170, 180, and 190 °C up to 13min and data were fitted to mathematical models. Additionally, an Arrhenius-type dependency with temperature was evaluated for all studied responses. More drastic frying conditions increased significantly (P ≤ 0.05) the furan content of fried samples. Furan formation followed a sigmoid trend with frying time only for frying temperature of 190 °C (RMS190°C : 7.6%). At lower temperatures, furan generation did not reach the asymptotic concentration level. Color change, lipid oxidation, and oil absorption increased with frying temperature and followed asymptotic relationships with frying time. For all evaluated temperatures, color change (RMS: 4.4% to 12.5%) and polar compound generation (RMS: 2.6% to 7.4%) presented good fit to a first-order kinetic model. Oil absorption was successfully fit to a mass balance-based model (RMS: 10.0% to 19.8%). Under the experimental conditions studied, only color change (EA : 15.47kJ/mol), lipid oxidation (EA : 6.67kJ/mol), and oil absorption (EA : 76.98kJ/mol) presented good fit (RMS: 0.7% to 6.3%) to an Arrhenius-type equation. Based on our results, the keeping of frying temperature below 180 °C and the reduction of the frying time would contribute to reduce not only the final furan occurrence in fried foods but also their oil content.