Studies on production and physical properties of neo-FOS produced by co-immobilized Penicillium citrinum and neo-fructosyltransferase

摘要

In this study, a co-immobilization process was developed to improve the production of neo-fructooligosaccharides (neo-FOS) by the neo-fructosyltransferase of Penicillium citrinum and to investigate its physicochemical properties. The optimal concentration of CaCl2 for the co-immobilization process was determined to be 0.25 M. In batch production, co-immobilization of whole cells together with neo-fructosyltransferase produced more neo-FOS (108.4 g/L) than did whole cell immobilization (49.4 g/L). In a study on water activity of neo-FOS, we found that the minimal concentration capable of inhibiting bacterial growth was about 42%, and that the minimal inhibitory concentration for fungal growth was about 68%. In terms of pH, neo-FOS was stable in the pH range of 7–10, but was degraded to an increasing extent with decreasing pH, and it was found to be thermally stable at food processing temperatures.