Microwave-assisted cellulose grafting for food packaging. Techno-economic comparative with other curing technologies

Abstract

Microwave-assisted cellulose grafting of eugenol was performed in order to incorporate bioactive capabilities to paper for food active packaging. The reaction was optimized using a Doehlert experimental design with three variables: power (200–300 W), time (120–240 s), and eugenol content (2–8 wt%) at constant molar ratio of BTCA:eugenol and SPHI:eugenol (2:1 and 1:1, respectively). The best bioactive paper properties (72.1% DPPH inhibition) were obtained at 230 W, 240 s, and 2 wt% eugenol. However, a high color difference was determined (ΔE* = 12.76) and poor mechanical properties are expected due to the high degradation obtained. A techno-economic study was performed between microwave curing and other as convection and infrared technologies. Despite paper final properties are slightly better in infrared technology; microwave-assisted allows reducing costs compared to convective or infrared technology (12.521 g of reagent/m2 and 0.015 kWh/m2 of paper respectively, i.e. 6.101 USD of total cost per m2 of paper produced).