Conversion of starch in to sugar during ripening of Tongka langit banana (Musa troglodytarum), a local Mollucan banana comodity, at different harvesting time

Tongka langit banana (Musa troglodytarum) is a native banana cultivar known for its high carotenoid content, particularly β-carotene, making it a promising functional food resource. Reliable assessment of ripening and shelf life is essential for preserving its nutritional value and optimizing postharvest utilization. This study evaluated postharvest physiological changes in Tongka langit bananas harvested at different maturity stages by examining the dynamics of starch content, total sugar content, and peel mechanical properties during storage. Fruits were harvested at 67 and 74 days after flowering (DAF) and stored for 0, 2, 4, 6, 8, and 10 days. Starch content, total sugar content, and peel hardness and elasticity were measured, and the data were analyzed using analysis of variance followed by Tukey’s test. The results showed that starch content declined markedly after six days of storage, accompanied by a corresponding increase in total sugar content. Bananas harvested at 74 DAF reached maximum sugar levels more rapidly than those harvested at 67 DAF. With prolonged storage up to ten days, starch content continued to decrease, while total sugar content initially increased and subsequently declined. Peel hardness and elasticity decreased progressively throughout storage. These findings provide new insight into the biochemical and physical ripening behavior of Tongka langit bananas and offer practical indicators for determining optimal harvest timing and postharvest handling strategies. Keywords: Tongka langit banana; harvesting time; ripening; starch and sugar content; peel properties.