Kinetics of furan formation during pasteurization of soy sauce

• The kinetic parameters of soy sauce are reported, including the apparent activation energy (Ea  ), enthalpy (ΔH≠θ) and entropy (ΔS≠θ).
• Furan formation in soy sauce is a zero-order reaction.
• The Arrhenius equation for furan formation during pasteurization for two brands of sauce are reported.
• Furan formation in soy sauce during pasteurization can be predicted based on these results.
• A simple, fast and accurate method for determination of furan in food is presented.

To investigate the kinetics of furan formation during pasteurization in soy sauce, the furan concentration in five samples was determined with Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) after hot water bath heating at 30, 50, 70, or 80 °C for 10 min to 7.25 h, respectively. The furan concentrations in soy sauce were 12–215 ng/mL. Furan formation in soy sauce is a zero-order reaction and the reaction rate constants were 3.71 × 10−9 mol/L.h for Pearl River Bridge brand (PRBB) soy sauce and 6.99 × 10−9 mol/Lh for Koon Chun brand (KCSB) at 80 °C respectively. In addition, by the Arrhenius equation and active complex theory, the apparent activation energy (Ea  ), enthalpy (ΔH≠θ) and entropy (ΔS≠θ) were summarized as the equations, lnk = −77237/RT + 6.61 and lnk/T = −74522/RT − 0.18 for PRBB, and lnk = −72018/RT+5.35 and lnk/T = −63301/RT + 0.08 for KCSB, where k is the rate constant, T is the absolute temperature and R is the universal gas constant. Ea  , ΔH≠θ and ΔS≠θ for PRBB are 77.237 kJ/mol, 74.522 kJ/mol, and −199.01 J/K·mol. Ea  , ΔH≠θ and ΔS≠θ for KCSB are 72.018 kJ/mol, 63.301 kJ/mol, and −209.72 J/K·mol. These results can be used to calculate or predict furan formation in soy sauce during pasteurization.