Green extract surface-coated electrospun cellulose nanofibers as an efficient, reversible, and reusable smart colorimetric sensor for real-time monitoring of chicken freshness

Abstract

Smart colorimetric sensor for the naked-eye detection of food freshness is considered as the most attractive tool in food safety. Herein, we prepared curcumin (CUR) coated electrospun regenerated cellulose nanofiber (RCA) composites (CUR-Cot), to monitor the real-time spoilage of raw chicken. The physicochemical properties of the CUR-Cot sensor were completely studied. The surface modification, morphology, crystalline nature, and thermal stability of CUR-Cot were investigated by using various spectral, analytical, and microscopic techniques. Based on the results, the successful coating of CUR on the surface of RCA was confirmed. Interestingly, the CUR-Cot showed a significant change in total color difference value (ΔE, 0 days − 0.0–14.93, after 1 day – 14.93–23.64, after 2 days – 23.64–44.78, after 3 days- 44.78–55.22, and after 4 days – 55.22–60.96, detectable by the naked eye) in the real-time monitoring for chicken freshness. In addition, the present CUR-Cot smart colorimetric sensor is reversible with change in pH, and the reversed sensor can be reused. Furthermore, the hydrophobic nature of the CUR-Cot was confirmed by water contact angle analysis (WCA, contact angle of 90 ± 3.00), which increases its application and adaptability. Good antibacterial, barrier, and optical properties of the present CUR-Cot were also found. Overall, the results confirm that the usage of CUR-Cot sensor can be highly efficient, user-friendly, and non-destructive for the real-time monitoring of chicken freshness.

Keywords

• Nanofibers
• Curcumin
• Cellulose
• Biosensor
• Naked-eye detection
• Food safety