AbstractAcid Hydrolysis of β‐D‐Fructofuranosyl Bonds. Generally, glycofuranosides are hydrolyzed at a higher rate than the glycopyranosides under identical conditions. The present paper is dedicated to the hydrolysis of β‐D‐fructofuranosides which are containing different aglycone moieties: methyl group, substituted methyl group (in inulin), glucosyl group (in sucrose) and substituted glucosyl group (in raffinose). The energies of activation were between 25.1 and 25.6 kcal/mole and the entropies of activation between 8 and 9.5 entropy units. The values of the reduced rate constants (values extrapolated to pH 0 and 100°C) depend on the size of the aglycone.The mechanism of splitting of ketofuranosides differs from that of the aldofuranosides and of aldopyranosides. According to the reported data these compounds are hydrolyzed by formation of a tertiary carbeniumcation, i. e. by plitting of the O‐fu