Effects of multifunctional films made of Luffa cylindrica L. Peel pectin on food freshness indicators, shelf-life extension of blueberries, and soil microorganisms

Abstract

As awareness of environmental protection becomes increasingly pronounced, functional sustainable packaging becomes more important in food applications. In this study, a multifunctional intelligent/active package was developed using pectin extracted from sponge gourd (Luffa cylindrica L.) peel as a film matrix combined with sponge gourd peel-derived ZnO-doped carbon dots (Zn–CD) and purple potato extract (PE). PE and Zn–CD synergistically altered the microstructure of the pectin film (PC), increasing its barrier properties, mechanical performance, antioxidant activity, antibacterial properties, UV resistance, pH color responsiveness, anticounterfeiting capabilities, and biodegradability. PC containing 5 wt% PE and 3 wt% Zn–CD (PC-5 %PE-CD) has strong pH sensitivity and can be used to determine milk and beef freshness based on changes in film color. PC-5 %PE-CD packaging is effective in prolonging blueberry freshness. In addition, compared with polyethylene film, PC-5 %PE-CD was not only easily degradable in soil but also capable of regulating soil microbial communities, providing nutrients for Brassica rapa L., promoting its growth, and enhancing the sustainability of resources. Therefore, the PC-5 %PE-CD composite can serve as a potential multifunctional and environmentally friendly sustainable food packaging material.