Influence of postharvest storage temperature, time, and invertase enzyme activity on sucrose and weight loss in sugarcane

Abstract

Sugarcane cultivars of two maturity groups, early and late were harvested in the months of March, April, May, and June 2007. The harvested sugarcanes were stored for 24, 48, 72, 96 and 120h. The average maximum and minimum atmospheric temperatures in these months were 35.5, 37.8, 39.8 and 40.9°C and 16.9, 18.4, 19.4, 20.8°C, respectively. Metabolic changes in the content of sucrose in sugarcane juice in relation to the activities of acid invertase (AI), neutral invertase (NI) enzymes, acidity, and loss in sugarcane weight were studied. Extractable sucrose percent in juice declined significantly with increasing storage periods and temperature. Activities of enzymes AI and NI showed a sharp increase during 0–120h of storage. Activities of both enzymes were significantly negatively correlated with the sucrose percent in juice. There was a rapid increase in acidity and loss in sugarcane weight during storage, and the rate was higher at higher temperatures. Significant differences in the reduction of sucrose percent in different cultivars during storage were found. These results might be helpful to minimize sucrose losses during storage of sugarcane from late harvests and for developing hybrids with improved storage properties.