Physical, mechanical, and optical properties of <i>enset</i> starch from bulla films influenced by different glycerol concentrations and temperatures

Abstract

Enset starch films were produced using glycerol as a plasticizer. The experiment was conducted using a factorial design with two factors: glycerol and temperature, to provide nine treatments. Glycerol concentrations were 15%, 20%, and 25%, while temperatures were 35°C, 45°C, and 55°C. Moisture content (9.18%–11.50%), water solubility (61.33%–65.60%), water absorption (26.53%–33.11%), water vapor permeability (3.65 × 10–10–5.92 × 10–10 g m−1 s−1 Pa−1), elongation at break (33.34%–39.56%), and transparency (78.46%–85.08%) showed significant (p < .05) differences due to the treatment with glycerol concentrations and temperatures. However, density (0.94–1.02 g/cm3), thickness (0.37–0.42 mm), tensile strength (4.03–4.84 MPa), L* (80.77–84.22), a* (4.04–4.94), b* (1.81–2.07), total color difference (11.13–14.07), whiteness index (80.82–83.76) were found to be significantly (p < .05) affected due to glycerol only. Generally, this work may substitute synthetic packaging material for low moisture content foods with minor modifications. Practical applications To date, the research focus of food packaging materials is targeting to replace the plastic polymer-based packaging materials by biodegradable and environmentally friendly kinds. This research has a practical application in the process of searching a sustainable biodegradable food packaging material input. The outcome of this research can be used as a base for further process in the development of food packaging materials from enset starch-based biopolymer. Hence, it can contribute to science and knowledge for academic and research aspects.