Amphiphilic starch/cinnamaldehyde inclusion compound and its fresh-keeping application in polyvinyl alcohol/gelatin antibacterial composite film

Abstract Plant essential oils have good antibacterial properties. However, due to their instability, there is still a particular gap with traditional antibacterial agents. Herein, polyvinyl alcohol/gelatin composite films were prepared by encapsulating the natural active antibacterial substance cinnamaldehyde with starch stearate (CMS-SA-CO) as an antibacterial agent. The structure, mechanical properties, degradability, antioxidant, antibacterial, and preservation properties of PGCC films were investigated. The results showed that the addition of CMS-SA-CO improved the film's tensile properties, hydrophobicity, and antioxidant activity. At the same time, the inhibition rates of E. coli and S. aureus were 98.54% and 95.31%, respectively. The prepared polyvinyl alcohol/gelatin composite films have good mechanical properties and excellent UV-blocking properties. The water degradation of the film showed that the degradation rate of PGCC reached 70%. Preservation experiments on cherry tomatoes showed that the PGCC film exhibited a certain freshness effect, maintaining a high acidity and soluble solid mass and a low weight loss rate. Therefore, composite films based on polyvinyl alcohol/gelatin and CMS-SA-CO have excellent application value. Graphical abstract