Life cycle of bioethanol production from blends of different food waste

Food waste offers a potential source for bioethanol production, but productivity depends on the chemical composition of the raw materials and the processes involved. However, assessment of the environmental sustainability of these processes is often absent and can be carried out using the Life Cycle Assessment (LCA) methodology. This study aimed to perform an LCA on bioethanol production from mixtures of different wastes, including tubers, fruits, and processed foods, focusing on the gate-to-gate phase. The inventory included a standard scenario and an optimized scenario, which eliminated drying and replaced the phosphate buffer with citric acid. To assess impacts and damages, the Ecoinvent 3.4 database and the ReCiPe 2016 method were used, while uncertainty analysis was carried out using Monte Carlo simulation with the aid of SimaPro software version 8.5.0.0. Results indicate that processed food blends generate the greatest environmental impacts in all scenarios evaluated. The fermentation stage is the largest contributor to environmental impacts and damage when energy consumption is considered. Without energy consumption, pretreatment and enzymatic hydrolysis become more significant. The most notable categories of environmental impacts and damages are Global Warming Potential (GWP) and Resources. The optimized scenario showed a lower environmental impact compared to the standard scenario, highlighting its potential for more sustainable bioethanol production.