Using soy protein SiOx nanocomposite film coating to extend the shelf life of apple fruit

Abstract

AbstractPreservation properties of soy protein isolate (SPI)/nano‐SiOx composite coatings to apple fruits were investigated. The sodium dodecyl sulfonate‐modified nano‐SiOx (SNS) particles were prepared by the ultrasonic method and the counter‐ion activation method, which products were designated as USNS and CSNS, respectively. The incorporation of CSNS particles was better than USNS to improve the preservation quality of the SPI film. The best conditions for the synthesis of the composite film were as follows: 10% SPI concentration, 0.3% nano‐SiOx dosage and coating time of 60 s. Under these conditions, the climacteric peak of apples was delayed to the fifth week. The apples also had better physiological indices than the control group. Nano‐SiOx particles were inlaid and evenly dispersed into the SPI film coatings. This work provides a simple CaCl2 pre‐activation method to produce SPI film coatings with good dispersion of nano‐SiOx particles for further preservation application of fresh fruits.