Abstract: Objective: To obtain the optimum process conditions for the synthesis of lactosucrose under the catalysis of β-fructofuranoside. Methods: Lactosucrose was prepared from lactose as an acceptor and sucrose as a fructosyl donor by a fructose-transferring enzyme, β-fructofuranoside derived from Arthrobacter sp.10138. The process was optimized by Box-Behnken experimental design followed by response surface analysis. Results: Adding the same volume of β-fructofuranoside solution to a mixture of lactose and sucrose in equal proportion by weight in aqueous solution to catalyze the reaction between the two sugars for 22.77 h at 35.0 ℃ provided optimum synthesis of lactosucrose, and the content of lactosucrose in reaction product was 22.70%. Conclusion: Combined use of Box-Behnken experimental design and response surface methodology has the feasibility to be used as a mathematical approach to optimize the synthesis process for lactosucrose, and the established model is reliable in predicting the content of lactosucrose in reaction product.

Key words: lactosucrose, β-fructofuranoside, Box-Behnken experimental design, response surface methodology