This study was executed to investigate the potential of agar-agar, a nontoxic and non-degradable
gelling agent, as a promising coating agent to improve and protect banana fruit
against fungal postharvest diseases i.e., crown, finger, neck and flower end rots which are
caused by fungal isolates of Colletotrichum musae and Fusarium moniliforme. Coated-ba-nana
fruit samples with different concentrations of agar-agar suspension particularly at
2.0 g · l−1 exhibited a significant reduction in incidence and severity of postharvest diseases
compared to untreated fruit. Banana fruits dipped in agar suspension at 2.0 g · l−1 for 5, 10
and 15 min showed significant reduction in disease incidence and severity. Moreover,
application of agar suspension as a coating agent at 2.0 g · l−1 significantly decreased
weight loss (%), firmness loss (%), and soluble solid concentration of banana fruit for
15 days at 25 ± 2°C. Scanning electron microscopy observation confirmed that the fruit
coated with agar colloid at 2.0 g · l−1 had significantly fewer cracks and showed smoother
surfaces than untreated fruit. This explains the quality improvement in agar-coated fruit
compared to uncoated fruit. Overall, agar colloid, a safe coating agent, could be used to
protect banana fruit against postharvest rot diseases and extend fruit storage life during
ripening and storage.