Preparation of plant-derived compounds/chitosan/gelatin antifungal film and investigation of its control effect on Zygosaccharomyces rouxii contamination in concentrated apple juice

The purpose of this work is to develop a plant-derived compounds (PDCs)/chitosan (CS)/gelatin (GL) packaging lining film with high inhibitory activity against the contamination of Zygosaccharomyces rouxii in concentrated apple juice. The PDCs with high anti - Z. rouxii activity were selected from 19 PDCs for pairwise combining, and the combination with synergistic anti - Z. rouxii effect was selected to prepare nanoemulsion. Then, the effect of PDCs emulsion on mechanical and anti - Z. rouxii properties of CS/GL film was investigated. Finally, the prepared PDCs/CS/GL film was used as packaging lining to explore the preservation effect on concentrated apple juice. The results showed that the combination of trans -cinnamaldehyde and geraniol (4:6, v/v) presented the highest synergistic anti - Z. rouxii effect (the value of fractional inhibitory concentration index equaling 0.25). Addition of trans -cinnamaldehyde-geraniol nanoemulsion reduced mechanical properties of CS/GL film, but improved anti - Z. rouxii activity. The CS/GL film containing 1.5 % (v/v) trans -cinnamaldehyde-geraniol nanoemulsion showed high anti - Z. rouxii activity and did not affect the quality of concentrated apple juice, which could be used as a packaging lining for preservation of concentrated apple juice. The PDCs/CS/GL packaging lining film prepared in this work not only presented an enduring and effective inhibitory effect on Z. rouxii contamination in concentrated apple juice, but also avoided the influences of trans -cinnamaldehyde and geraniol on the quality of concentrated apple juice, which provided a new idea for the development of food preservation packaging film.