Environmental impact of peanut skin-reinforced native starch foams modified by acetylation

Abstract

Starch foams are natural and biodegradable alternatives proposed as sustainable replacements to expanded polystyrene. Despite being recognized as eco-friendly materials, environmental impacts associated with their production process remain poorly studied. Here, the cradle-to-gate life-cycle assessment of four types of starch-based foams (potato, cassava, corn, and sweet potato) reinforced with peanut skin was assessed and analyzed. Chemically modifying starch by acetylation may accelerate the degradation ratio and decrease its hydrophilicity, which is a common issue in packaging applications. Hence, two starch scenarios were evaluated, considering as-prepared and acetylated starches. The environmental burden of starch foam production varied depending on the starch source due to the different agricultural and irrigation practices. By incorporating 10 wt% of acetylated starch, the environmental impact drastically increased in most categories. Additionally, the sensitivity analysis carried out with different peanut skin contents showed a limited effect under 0–30 wt% of peanut skin, suggesting that peanut production exhibits a similar environmental burden to most starches.