Edible Film Based on Rambutan Seed (Nephelium lappaceum) Starch: An Alternative Biodegradable Food Packaging

This study evaluated the quality and characteristics of edible films derived from rambutan seed (Nephelium lappaceum) starch (3% and 4%) using glycerol and sorbitol as plasticizers at concentrations of 1.0%, 1.5%, and 2.0% (w/v). The optimal formulation was produced using 4% starch combined with 1% (w/v) glycerol and 1% (w/v) sorbitol, exhibiting favorable properties, including thicknesses of 0.24 and 0.22 mm, tensile strengths of 6.90×10^-3 and 12.06×10^-3 N/mm², elongations of 38.97% and 4.44%, elasticities of 1.770×10^-3 and 6.98×10^-3 kgf/mm², and water absorption rates of 33.3% and 50.0%. Fourier transform infrared spectroscopy analysis confirmed that the film formation involved physical blending without the formation of new functional groups. Scanning electron microscopy revealed that sorbitol provided better compatibility with rambutan seed starch than glycerol. The results of biodegradability tests demonstrated complete degradation of the edible films within seven days, underscoring their environmental sustainability. Rambutan seed starch can be a promising precursor for the development of low-cost and eco-friendly film for packaging applications.