AbstractModifications have been made to a periodate oxidation procedure originally described by Rappaport et al.1,2 These have resulted in a procedure suited to the routine determination of a wide range of carbohydrates in solution, including soluble sugars, sugar alcohols, oligosaccharides and the hydrolysis products of reserve polysaccharides. A reasonably accurate estimate of fructose in a mixture of sugars is possible by the determination of the periodate consumption of aliquots before and after the destruction of fructose.An improved ferricyanide method is suited to the determination of reducing sugars.Both methods may be applied with equal success to hexose and pentose sugars. When used in conjunction, the two methods enable the estimation of fructose, reducing sugar, sucrose and sugar alcohol in aliquots of the same extract.