Immobilizing laccase on electrospun chitosan fiber to prepare time-temperature indicator for food quality monitoring

• Published in: Innovative food science & emerging technologies 2020-07, Vol.63, p.102370, Article 102370
• Main Authors: Jhuang, Jhao-Rong, Lou, Shyi-Neng, Lin, Shih-Bin, Chen, Shih Hsin, Chen, Li-Chen, Chen, Hui-Huang
• Format: Article
• Language: English
• Subjects: Chitosan; Electrospin; Intelligent packaging; Laccase; Time-temperature indicator
• ISSN: 1466-8564; 1878-5522
• DOI: 10.1016/j.ifset.2020.102370

Laccase was immobilized on the electrospun chitosan/poly(vinyl alcohol) fiber (ceCPL) with specific area of 17.05 m2/g to reinforce the stability of enzymatic time–temperature indicator (TTI). The ceCPL exhibited a high relative activity within 4 °C–40 °C and the activation energy (Ea) of coloration with guaiacol approached 40.9 ± 2.8 kJ/mol for 80 μg/cm2 of ceCPL-immobilized laccase. In dynamic temperature response experiments of ceCPL using intermittent temperature changes between 4 °C and 25 °C, irreversible inactivation did not occur, indicating the desirable tolerance and sensitivity of ceCPL to temperature alterations. Approximately 1 or 38 days was required to reach the endpoint of coloration at 4 °C when 80 or 8 μg/cm2 of laccase were immobilized on ceCPL, respectively. The regression equation derived from kinetic model analysis was conducted and could be further utilized to design a suitable time–temperature indicator (TTI) to monitor food quality according to the color change of ceCPL coloration. •Laccase was immobilized on electrospun chitosan fiber with high surface area.•Immobilized laccase exhibited a high relative activity within 4 °C–40 °C.•Adjusting the laccase amount on chitosan fiber expands active energy range of TTI.•Desirable coloration of TTI was observed in the dynamic temperature response test.•Laccase TTI provides quality information based on time-temperature history.