A method for suppressing post-harvest biological infestation in fruits, such as bananas, plantains, and pineapples, is provided. The method involves treating the cut or separated areas of the fruit by applying a composition containing: (a) a synthetic film-forming thermoplastic polymer in an amount effective to suppress biological infestation and disease of the fruit when applied; and (b) an oil or aqueous emulsion carrier. Application of these coating compositions may be performed by dipping, extrusion, spraying, or brushing at ambient or elevated temperature, depending on the nature of the coating. The resulting coatings reduce the exposure of the fruit to fungal spores, oxygen, moisture and microorganisms, diminish the occurrence of fungal growth, limit infection, and inhibit microbial growth.