Enzymatic Synthesis of the Fructosyl Derivative of Sorbitol

The aim of the study was to determine the effect of selected reaction parameters-temperature (37-57 degrees C), pH (5.8-7.9), substrates ratio (sucrose/sorbitol 0.5/1.5 to 1.5:0.5 (m/m)), and the presence of NaCl-on the course of fructosyl-sorbitol synthesis with an enzyme preparation (11 760 U/100 g of sucrose) containing fructosyltransferase and beta-D-fructofuranosidase from Aspergillus niger. A mixture of at least three fructosyl sorbitol derivatives was obtained: two mono-fructosyl and one di-fructosyl. The highest content of all sorbitol derivatives combined was 2.7 g/100 mL for pH 6.8-6.9, and the sucrose/sorbitol ratio was 1:1. Increasing the reaction temperature from 37 to 57 degrees C reduced the time required to reach the maximum product content from 5 to 2 h, while the concentration did not increase. The addition of NaCl (0.63 M) extended the reaction time from 2 to 5 h and slightly lowered the maximum concentration of sorbitol derivatives (from 2.74 to 2.6 g/100 mL).