Optimisation on the production of biodegradable plastic from starch and cassava peel flour using response surface methodology

Biodegradable plastic is starch-based plastic that can be naturally decomposed by microorganisms. Cassava is one of the primary starch-producing plants. The increasing amount of cassava production increases cassava peel waste. Cassava peel has 50% of the starch content in the tuber. The factors that are affecting the production of biodegradable plastics are temperature and drying duration. This study aimed to obtain the optimum temperature and drying time to produce biodegradable plastics from starch and flour of cassava peel waste. Response Surface Methodology (RSM) with a Central Composite Design (CCD) method was employed. The experimental design included two factors and three responses. The first factor was the drying temperature (40 °C, 50 °C, and 60 °C) and the second factor was the drying duration (5 hours, 6 hours, and 7 hours). The responses measured were tensile strength, elongation, swelling and biodegradability. The study found that the optimum condition of the process was at the drying temperature of 57.79 °C and drying duration of 5 hours. At this optimum condition, the biodegradable plastic produced has the tensile strength of 2554.65 N/m2; elongation of 16.67%; and swelling of 124.17%. Biodegradation testing for 12 days resulted in a mass reduction of 58.30%.