Abstract: A process for the production of hemicellulose derived monosaccharides comprising: (a) contacting an aqueous hemicellulosic stream with a C3-8 alkyl alcohol at elevated temperature and acidic pH to produce a reaction mixture comprising at C3-8 alkyl ester and a hemicellulose-derived monosaccharide; and (b) separating the reaction mixture obtained from step (a) into an aqueous phase comprising said hemicellulose-derived monosaccharide and an organic phase comprising said C3-08 alkyl ester. The product of step (b) may be further processed using an optional step: (c) reacting said hemicellulose-derived monosaccharide obtained from step (b) with a metal hydroxide or a quaternary ammonium hydroxide to produce a metal lactate or quaternary ammonium lactate.