Succinylated Soy Protein Film Coating Extended the Shelf Life of Apple Fruit

The present study investigates the properties of acylated protein film and its application to apple preservation. Succinylated protein improves the film‐forming index better than palmitoylated protein. The globular molecules of the acylating modified protein were destroyed, its internal groups were exposed, and its peptide chain was expanded; thus, the tensile strength and elongation of the film were increased. Moreover, the best conditions for the production of the composite film were: 10% acylated soy protein isolate, 0.34% chitosan, 0.2% stearic acid and soaking for 60 s. Under these conditions, the breathing climacteric peak of apples appeared in the third week, which is a week longer than the control group; thus, the apples with the coating had better physiological indices than the controls. Our work provides a novel approach where the protein chains are coupled with covalent agents to produce a good substrate protein for further film application. Practical Applications The edible composite film will be produced in the industry according to the technology provided in our paper, which can be used for the shelf life extension of the fruit products.