Characterization of vinasses from five certified brands of origin (CBO) and use as economic nutrient for the xylitol production by Debaryomyces hansenii

Vinasses coming from the five CBOs of Galicia, north-western Spain, were characterized, and successfully employed as economic nutritional supplements for xylitol production by Debaryomyces hansenii. All fermentations can be modelled showing kinetic patterns fairly described by the mathematical models. No negative effect of the phenolic compounds in the liquid phase on the initial volumetric rate of product formation (rP0) was observed. Multiple linear regression analysis was used to describe the effect of metals and initial xylose acting on Pmax and YP/S. Zn was the most influential variable. Besides, partial least-squares regression models show a clear separation, based on the first two principal components, between the whole vinasses and the liquid fractions, which provided the higher Pmax, with the exception of CBO 4, where Pmax = 40.4 g/L, was achieved using the solid and liquid fraction.