Abstract: An improvement in a process for the production of xylose or xylitol wherein a vegetable material is contacted with a basic substance and the solid residue is thereafter treated with an acid, the improvement resides in the use of stone nut shells, in employing a two-stage digestion initially with a 1.5-6 molar alkali metal hydroxide solution at 10.degree.-50.degree. C. and thereafter diluting the digestion mass to 0.75 molar or less and digesting at a temperature of at least 60.degree. C.

Abstract: Process for the two-stage decomposition of hemi-celluloses of xylan-containing natural products for the purpose of obtaining xylose and xylitol where the starting material is treated in the first stage with a basic medium and the obtained solid residue is subjected in a subsequent stage to an acid treatment wherein the alkaline and acid stages are carried out in a single reaction vessel.

Abstract: A method for the preparation of xylose solutions from oat husks which comprises:A. hydrolyzing oat husks with a solution of alkali metal hydroxide to provide oat husks from which the chemically bound acetic acid originally present therein has been substantially completely removed, and a solution of acetic acid, provided, that a quantity of not less than one mole, and not more than two moles, of said solution of alkali metal hydroxide is used per mole of acetic acid originally present in the oat husks;B. recovering the oat husks from which the chemically bound acetic acid has been substantially removed; andC. hydrolyzing the oat husks of step (b) with a mineral acid to provide a solid residue containing lignin and an acidic solution of D-(+)-xylose.