Abstract:
Nowadays, the increasing trend in health & wellness accelerate the demand in healthy ingredients including low-calories sweeteners. Thailand, which has abundant of sugar supply, can add values to sugar by converting it to fructooligosaccharide (FOSs). In this research, the production of FOSs using levansucrase and inulosucrase in free enzyme stirred reactors and immobilized enzyme packed bed reactors were investigated. The FOSs productions with 500 U of enzymes were perform in 50 ml of 50% (w/v) sucrose solution. The sucrose conversions and FOSs yields were in the range of 60.16 to 95.52 % and 9.37 to 47.22 % respectively. It was found that enzyme immobilized on core-shell chitosan beads (CSB) had higher sucrose conversions and higher FOSs yields than those on hydrogel chitosan beads (HGB).The five cycles stability test showed that enzymes immobilized on CSB had greater stability than those on HGB. Moreover, the FOSs production using mixed levansucrase and inulosucrase immobilized on CSB was tested and showed higher FOSs yield than the case of using only levansucrase. The kinetic models were also determined using EQUATRAN with regression analysis. The transfructosylation reaction dominated the overall reactions but levansucrase had higher rate of hydrolysis reaction than inulosucrase.