Each mango was carefully washed with water to remove debris and possible preservatives on the surface and then dried in the ambient air before coating. Coating experiments were carried out on the same day as the date of purchase. The mangos were divided into three groups. There were at least 10 fruits in each group. These included an untreated group (CK), a group coated with a bentonite suspension only (A: Deionized water:bentonite = 1:15), and another group coated with a suspension of bentonite loaded with potassium sorbate (B: Deionized water:bentonite = 1:15:0.07). The bentonite suspension was prepared by continuous stirring of deionized water and bentonite for 1 h immediately before application.
Bentonite/potassium sorbate suspensions were similarly produced but with an additional mass of potassium sorbate added to the mixture before stirring. The appropriate coating was applied to each mango three times using a brush.