Abstract

Sugar cane accumulates in its stalks sucrose and, later, polysaccharides including fructans. These polysaccharides are hydrolyzed by a fructanase which requires Mn2+ to act. Since these fructans are heteropolymers containing both fructose and galactitol, the enzyme must contain at least two different hydrolase activities. During the first 2 days of post-collection impairment, fructanase activity rapidly develops and, then, it decreases and stabilizes. The decrease in the amount of mid-molecular weight carbohydrates after the fourth day of post-collection impairment can be seen as a consequence of the stabilization of fructanase activity. This hydrolase is inhibited by an excess of Mn2+ as well as by reducing sugars accumulated in the juices.