DEVELOPMENT OF TURMERIC LEAF ESSENTIAL OIL INCORPORATED ACTIVE PACKAGING FILM FOR FOOD APPLICATIONS

Abstract

The present study aimed to develop and evaluate a biodegradable active packaging film by incorporating turmeric leaf essential oil (TLEO) into a starch-chitosan matrix for food packaging applications. Turmeric leaves, an underutilized agricultural by-product, were utilized as a sustainable source of bioactive essential oil. TLEO was extracted by hydrodistillation using a Clevenger apparatus and incorporated into starch-chitosan films at concentrations of 0, 1, 2, 3, and 4% (v/v) using the solvent-casting method. The developed films were characterized for mechanical and physical properties, including thickness, force at break, elongation at break, bursting strength, and colour. Their preservation efficacy was evaluated by determining the total plate count (TPC) of refrigerated sardine samples wrapped with the films, while insect-repellent activity against Sitophilus oryzae was also assessed. The incorporation of TLEO significantly improved the mechanical performance of the films. Film thickness increased from 0.084 to 0.208 mm, bursting strength from 23.67 to 30.33 psi, force at break from 1.37 to 5.83 N, and elongation at break from 0.90 to 9.00 mm as TLEO concentration increased to 4%. Colour analysis showed a gradual decrease in lightness and an increase in yellowness with increasing essential oil concentration, confirming the successful incorporation of TLEO into the polymer matrix. Antimicrobial evaluation revealed a concentration-dependent reduction in microbial growth during refrigerated storage of sardine. The film containing 4% TLEO exhibited the best preservation performance, maintaining the total plate count at 6.73 log CFU g⁻¹ after seven days of storage compared with 7.51 log CFU g⁻¹ for the control film. Repellency studies also demonstrated enhanced insect-repellent activity with increasing TLEO concentration. Based on the combined evaluation of mechanical properties, antimicrobial efficacy, and insectrepellent activity, the starch-chitosan film containing 4% TLEO was identified as the optimum formulation. The study demonstrates that turmeric leaf essential oil, obtained from agricultural waste, can be effectively utilized to produce environmentally friendly active packaging films with improved mechanical strength, antimicrobial activity, and insect-repellent properties, highlighting their potential as sustainable alternatives to conventional petroleum-based food packaging materials.