Arrowroot Starch–Based Edible Coatings Containing Lemongrass Essential Oil Emulsion for the Postharvest Preservation of Giant Umbu

Giant umbu is a highly perishable tropical fruit whose rapid ripening limits its distribution and availability, yet postharvest studies for this species remain scarce. To address this gap, the present study evaluated the effectiveness of arrowroot starch–based edible coatings incorporating emulsions containing different concentrations of lemongrass ( Cymbopogon citratus ) essential oil (EO) in extending postharvest shelf life. A completely randomized design was adopted, considering time and EO concentration as experimental factors, with seven treatments: uncoated fruit (WC), starch‐only coating without emulsion (CWE), and coatings formulated with EO emulsions at 0%, 0.4%, 0.6%, 0.8%, and 1.0% (C0, C0.4, C0.6, C0.8, and C1.0, respectively). All coatings contained 4% ( w / w ) arrowroot starch as the matrix. Fruits coated with emulsions containing EO showed reduced softening during storage, particularly treatments C0.8 (firmness decreased from 27.88 ± 2.77 to 39.05 ± 1.25 N from Day 0 to Day 9) and C0.6 (34.69 ± 5.96 to 36.63 ± 4.59 N), as well as the CWE treatment (32.94 ± 3.77 to 31.52 ± 2.31), indicating modulation of gas exchange and attenuation of ethylene‐related tissue degradation. Dark spot incidence was effectively controlled in all EO‐containing coatings, whereas uncoated fruits exhibited visible epidermal lesions by Day 9. These results suggest that citral‐rich EO emulsions can inhibit the onset of postharvest disorders and delay quality loss. Overall, the findings provide new insights and practical contributions for developing postharvest preservation strategies for giant umbu, a crop for which technological information remains limited.