Super protective effect, ultra-high juice absorption and long-term antibacterial of Ag-2MI@Chitosan biodegradable sponge for fruit preservation and transportation

Plastic foam packaging is often used for the transportation to avoid mechanical damage to the fruit, but it lacks antibacterial properties, water absorption and is non-degradable, leading to fruit decay and safety risks as well as serious environmental pollution. Herein, Ag-2-Methylimidazole@Chitosan (Ag-2MI@CS) was successfully synthesized by in situ synthesis at normal temperature and pressure, and improved the antibacterial performance of Ag-2MI@CS by using green solvent ethanol to adjust the solvent polarity. The results showed that the long-lasting inhibitory performance of Ag-2MI@CS was significantly improved, the long-lasting antibacterial time has been extended from 24 h to 96 h. Furthermore, Ag-2MI@CS can significantly protect fruits and reduce the damage of fruits, even when falling from a height of 60 cm or under extreme transportation conditions. Besides, Ag-2MI@CS had extremely high absorption rates of water and fruit juice, 1447.69 % and 1356.59 %, respectively, which was conducive to absorbing water generated by respiration and juice generated by damage during transportation, so as to avoid the growth of bacteria caused by water and fruit juice. Ag-2MI@CS can achieve fruit preservation in both indoor static and transportation dynamic conditions. This study offers novel insights into new biodegradable packaging material in fruit transportation.