The enzymatic production of lactulose via transglycosylation in conventional and non-conventional media

In this study, lactulose production with β-galactosidase from Kluyveromyces lactis in aqueous and non-conventional media was studied. The optimisation of the rate of enzymatic lactulose production in aqueous media was carried out using factorial design methodology. The results showed a statistically significant effect of both lactose and fructose levels – as well as their interaction – on the rate of lactulose production. Maximum lactulose production rate was obtained at fructose and lactose concentrations of 25–30% (w/w) and 9–12% (w/w), respectively. The addition of acetone had a negative effect on lactulose production, whereas the incorporation of triethyl phosphate up to a concentration of 30% (w/w) caused an increase of up to 20% in the lactulose production.