BACKGROUND: The work describes the synthesis of isoamyl butyrate, a fruity banana flavour using immobilised lipase [EC 3.1.1.3] as a biocatalyst in a solvent-free system, under mild optimised reaction conditions. Kinetic modelling with Ping Pong Bi Bi models, and thermodynamic parameters were evaluated at different temperatures. RESULT: The optimised parameters of temperature, mole ratio and enzyme loading attained 96% maximum conversion of ester in 10 h. Novozym 435 was successively recycled nine times with 33% loss of initial enzyme activity. The kinetic parameters were found as: maximum rate constant (V-max)= 28.027 mmol min(-1) g(-1) (of catalyst), rate constant for acid (K-a)= 0.636 mol L-1, rate constant for alcohol (K-b)= 0.657 mol L-1, rate constant for alcohol inhibition (K-ib)= 0.022 mol L-1 at optimum conditions by varying initial concentration of acid from 1.5 to 8.3 mol L-1 and concentration of alcohol from 2.12 to 7.9 mol L-1. The possibility of mass transfer resistance was investigated using an effectiveness factor which was determined as 1. CONCLUSION: From kinetic modelling, the esterification reaction was found to obey the Ping Pong Bi Bi mechanism with substrate inhibition. From thermodynamic evaluation the activation energy (E-a) for reaction, Gibbs free energy change (Delta G), and the enthalpy change (Delta H) was obtained as 16 kJ mol(-1), 71 kJ mol(-1) and 13 kJmol(-1), respectively. (C) 2016 Society of Chemical Industry