Sugarcane-derived Bio‐Amine‐Responsive Colorimetric Films for real-time visual monitoring of the seafood freshness

A new type of bio-amine-response colorimetric film with excellent flexibility and biodegradability was fabricated by the main components of sugarcane, including sugarcane skin anthocyanin (SSA), bagasse cellulose fibers (CF), and cellulose nanofibers (CNF). Benefiting from the rich hydroxyl groups and large specific surface area of CNF, the sample of adding 10 wt% CNF in CF (CF/CNF10/SSA) presented good mechanical properties (33 Mpa), reusability (10 cycles), excellent color change (ΔE>5), and excellent antioxidant properties (the free radical scavenging rate of ABTS: 86%). Furthermore, the film had good water resistance (water contact angle only decreases about 20° after 60 s), color stability up to 28 days, and rapid response to ammonia (1–2 s). Thus, CF/CNF10/SSA was successfully used as a low-cost, inoxidizable, and pH/NH3 responsive smart tag to monitor the freshness of seafood in real-time, achieving the high-value utilization of sugarcane waste components.