Yeast cell immobilization on the P. chrysogenum and suitability
of the immobilized biocatalysts for sweet wine production was
confirmed by satisfactory operational stability during repeated
batch fermentations of must of dried grapes, with no loss of
integrity or activity. The wines obtained by fermenting raisin musts
contained greater amounts of volatile compounds. Successive reuses
of immobilized cells may reveal an adjustment or adaptation
to the fermentation medium and a more uniform behaviour as
regards fermentation kinetics and production of some metabolites.
Also, the immobilization method used allows biocapsules to be
withdrawn from the medium when desired, which expedites the
process, saves costs and shortens the fermentation time.