Production and Evaluation of a Seaweed-Based Bioplastic Sheet for Food Packaging

In 2020, global plastic waste production reached 367 million metric tons, a figure anticipated to escalate in the future. India, ranking fifth worldwide in plastic waste output, confronts significant challenges due to plastic pollution, a pressing environmental issue. Addressing this problem requires a departure from petroleum-based plastics. Seaweed-based bioplastics have emerged as a sustainable alternative, gaining attention for their versatility, particularly in food packaging applications. Approximately 1 kg of wet Kappaphycus alvarezii, a red seaweed, was boiled in 1L of distilled water for 15 minutes and then filtered, yielding roughly 98% crude jelly polysaccharides. The resulting mixture was air-dried, yielding about 5% (50 g dry weight from 1 kg wet weight) of dry crude polysaccharide. To produce bioplastic, 6 g of dry crude polysaccharide was combined with 3 mL of glycerol and 3 mL of vinegar, then mixed in 100 mL of distilled water. The mixture was heated in a water bath at 100°C for 7 to 10 minutes, cast into a sheet, and left to cool for 2 days. Various mechanical properties were evaluated, including a maximum force of 5.85N, tensile stress of 3.65 MPa, tensile strain at the break of 10.38%, and tensile stress at the break of 2.54 MPa, which are critical for assessing materials in food packaging. These parameters provide insights into strength, flexibility, and ultimate stress under tension. Additionally, the identification of functional groups through frequencies and wavelengths, such as OH stretch, C-C stretch, and C-O stretch, offers valuable information on moisture interactions and structural integrity, enhancing the material's suitability for food packaging. Seaweed-derived bioplastics, especially those containing crude carrageenan, offer a sustainable and eco-friendly alternative to traditional plastics. They are biodegradable and renewable, naturally decomposing through microbial and marine organism activity, thereby reducing their environmental impact. Unlike fossil fuel-based plastics, carrageenan-based bioplastics degrade naturally over time. Seaweed-derived carrageenan is deemed safe and compatible with animal consumption. Unlike conventional plastic packaging, seaweed-based plastic does not pose a risk of clogging in the digestive systems of terrestrial or marine animals. This highlights their potential to significantly diminish the ecological footprint associated with plastic waste.