Effect of Manihot esculenta Edible Coating Blended with African Basil (Ocimum gratissimum) Essential Oil on the Shelf-Life of Mango Fruits

Abstract
Aims: To establish the shelf -life of mango fruits coated with unmodified and modified M. esculenta edible coating at low (4 ± 2°C) and room temperature (23 ± 2°C) conditions. Place and Duration of Study: The study was done at Moi University, School of Sciences and Aerospace studies, Department of Chemistry and Biochemistry between January 2021 and June 2021. Methodology: Ocimum gratissimum leaves essential oils was obtained by hydro-distillation method using Clevenger apparatus. Preparation and modification of the coating were homogenized at 70 ± 2 °C. Physico-chemical parameters including weight loss, titratable acidity (TA), Vitamin C concentration, total soluble solids (TSS), and pH were used to establish the fruits’ shelf-life. Results: The modified M. esculenta (cassava) starch coating (1.5%) treatment, their interactions and storage duration significantly affected the physico-chemical parameters of mango fruits. The modified coating-maintained TA 0.66%, 0.87%, reduced weight loss by 27.81%,14.62%, delayed the increase of TSS 7.50%, and pH 5.20, 4.93 while retaining the vitamins C 8.13 mg/100g, 15.09mg/100g concentration up to eighteen days and twenty-seven day of storage at 23 ± 2°C and 4 ± 2°C respectively. The distilled water treatment (control) reduced TA to 0.11%, 0.23%, increased weight loss to 47.12%, 24.21%, TSS 20.22%, 17.41%, and pH 8.21, 5.20 while retaining the vitamin C 3.74 mg/100 g, 8.13 mg/100 g concentration at 23 ± 2°C and 4 ± 2°C respectively. Conclusion: Results of the present study showed that M. esculenta edible coating incorporated with O. gratissimum essential oil extended the shelf life of mangoes up to eighteen and twenty-seven days of storage at room temperature (25 ± 2°C) and low temperature (4 ± 2°C), respectively. This treatment might be an effective farm-based post-harvest treatment in prolonging the shelf life of fresh produce while maintaining their physico-chemical parameters.