2018 ASHS Annual Conference

Banana (Musa spp.) is one of the most popular fruits worldwide, because of good taste, nutrition, and health aspects. The major postharvest concern of banana fruit is browning which reduces the marketing value and the attractiveness of fruits. The current study was designed to determine the influence of cultivar, and stage of maturity on degree of browning, polyphenol oxidase (PPO), and peroxidase (POD) in banana peel and pulp tissue. Banana cultivars varying in genome, including ‘FHIA 1’ (AAAB), ‘Hua Moa’ (AAB), ‘Kandarian’ (ABB), ‘Pisang Raja’ (AAB), ‘Saba’ (ABB) and ‘Williams’ (AAA) were harvested at full three-quarter stage of maturity and room ripened at 20^oC and 95% relative humidity. Samples were separated into four ripening stages (mature green, transition, ripe, and overripe) and total phenolics, degree of browning, PPO and POD enzyme activity of fruits were analyzed. Measured total phenolics in peel was higher than pulp in all cultivars except ‘Williams’. ‘Hua Moa’, ‘Kandarian’, ‘Pisang Raja’, and ‘Williams’ showed the highest total phenolic content at ripe and over ripe stages in peel and pulp tissues. Degree of browning increased in all cultivars with advancing of maturity in peel and pulp tissues. ‘Hua Moa, and ‘Pisang Raja’ had the highest values of degree of browning. Whereas, ‘FHIA 1’, and ‘Saba’ showed the lowest values. The results also indicate that PPO activity of pulp was higher than peel in all cultivars. In addition, activity of PPO varied in cultivars with different genomes. ‘Hua Moa’, ‘FHIA 1’, ‘Pisang Raja’, ‘Williams’, ‘Kandarian’, and ‘Saba’ had the highest to lowest PPO activity in banana fruits peel. In pulp tissue, ‘Hua Moa’, had the highest and ‘Kandarian’, ‘Saba’, and ‘Williams’ had the lowest PPO activity. The highest activity of POD was observed in ‘Hua Moa’ for both peel and pulp tissue. However, POD did not show any significant activity in peel tissue of ‘Kandarin’, ‘Pisang Raja’, ‘Saba’, and ‘William’s. This study helps to understand the role of polyphenol oxidase (PPO) and peroxidase (POD) as two of the major enzymes involving in enzymatic browning in banana peel and pulp tissue.