Effects of harvest age and postharvest nano-calcium application on the physicochemical characteristics of MD2 clone pineapple (<i>Ananas comosus</i> L.) in a room temperature storage

Abstract Pineapple ( Ananas comosus L.) is a popular tropical fruit with high economic value. The quality of pineapple fruit is influenced by various factors, one of which is harvest age. Nano-calcium is expected to strengthen the fruit’s cell walls, thereby extending shelf life and reducing damage caused by postharvest physiological processes. This study aimed at determining the effects of harvest ages and postharvest dipping in nano-calcium solutions on the physicochemical characteristics of MD2 clone pineapple in room temperature storage. The research was conducted from June to August 2023, arranged in a 2 x 4 factorial of a completely randomized design with 4 replications. The first factor was fruit age (137 and 146 days after flowering) and the second one was nano-calcium treatment (control/without nano-calcium, 20, 40 and 60 mL/L). The results showed that harvesting at 137 DAF significantly resulted in lower changes in skin color, total soluble solids, TSS/TA ratio and beta-carotene, but increased fruit acidity, vitamin C and water contents. Early harvest at 137 DAF did not significantly affect weight loss or firmness. Post-harvest application of 20 mL/L nano-calcium significantly reduced weight loss but increased skin color changes. No significant differences were observed in fruit firmness, sugar content, acidity, vitamin C and beta-carotene content with nano-calcium application. The combination of early harvest and nano-calcium treatment generally does not significantly affect fruit quality, except the combination of 137 DAF and 20 mL/L nano-calcium that significantly reduced fruit weight loss.