The scale-up of inulinase production in aerated cultures of Candida kefyr DSM 70106 was studied, taking into account the criterion of maintaining K(L)a constant. The culture was carried out batchwise, in a 15-L fermenter, with K(L)a varying from 25 to 199 h(-1). The highest inulinase production was attained with an initial K(L)a value of 46 h(-1). A large scale fermentation (300-L fermenter) was performed using identical culture medium conditions. The responses obtained for the bench and scaled-up experiments showed similar behaviors, and the results were, respectively, 0.60 and 0.58 U . mL(-1). h(-1) for productivity and 43.0 and 41.5 U . mL(-1) for activities.