It is known from European Patent No. 421,882, of which the Applicant is proprietor, to obtain xylitol syrups having a xylitol content of 80% to 90%, the remainder being essentially composed of D-arabitol, pentitol of the natural D series of sugars. These syrups, which are not very viscous and which are particularly well adapted to the crystallization of xylitol, are obtained by microbiological conversion of glucose to D-arabitol, microbiological oxidation of D-arabitol, to D-xylulose, enzymatic isomerization of D-xylulose to D-xylose and then catalytic hydrogenation of the mixture of D-xylulose and D-xylose to xylitol and D-arabitol. These xylitol syrups, which do not contain L-arabitol or galactitol but only D-arabitol as accompanying polyol, permit easy extraction of three crops of pure xylitol crystals.
