STUDIES ON ASCORBIC AND CITRIC ACID CONCENTRATIONS IN PINEAPPLE FRUIT AT RIPENING STAGES

This study evaluated the changes in ascorbic acid (vitamin C) and citric acid concentrations in pineapple (Ananas comosus L.) at three distinct ripening stages: unripe (Sample C), semi-ripe (Sample B), and fully ripe (Sample A). Fruits were harvested and allowed to ripen naturally for 0, 2, and 4 days respectively, then analyzed using standard titrimetric methods. Results revealed that ascorbic acid content increased progressively with ripening, from 16.43 mg/100 mL in unripe fruit (Sample C) to 20.83 mg/100 mL in semi-ripe (Sample B) and reaching the highest value of 23.48 mg/100 mL in fully ripe fruit (Sample A). Conversely, citric acid concentration decreased significantly as ripening advanced, recording 82.9 mg/100 mL in unripe fruit (Sample C), 64.03 mg/100 mL in semi-ripe (Sample B), and 57.63 mg/100 mL in fully ripe fruit (Sample A). These changes reflect a reduction in acidity and enhancement of sweetness and nutritional value (particularly vitamin C) as the fruit matures. Fully ripe pineapples therefore offer superior nutritional quality and consumer acceptability, whereas unripe and semi-ripe fruits, with higher acidity, are better suited for industrial processing requiring greater citric acid content. The findings underscore the importance of harvesting and utilization timing for optimizing fruit quality, nutritional benefits, and postharvest applications, and recommend further studies on varietal and environmental effects on acid metabolism in pineapple.