From food-waste to compost and feed: Life Cycle Assessment of a pilot plant of insect mass-rearing

Food waste is a problem that urgently requires strategies for facing it. In this context, the potential environmental impacts of food-waste bioconversion by the action of Hermetia illucens into compost and dried larvae, are assessed, through the application of Life Cycle Assessment. Two different functional units, used for carrying out the analysis, are selected: 1) the input of production process (1 tonne of food-waste); 2) the output composed by dried larvae, considering the protein content (1 kg). Results, in terms of Global Warming Potential (GWP), show a value of 30.2 kg CO2 eq, mainly due to the electricity consumption and direct GHG emissions. Instead, comparing the utilisation of H. illucens for protein production, instead of soy meal (considering 1 kg of protein) caused an increase in GWP and Energy Use (EU) of 0.4 kg CO2 eq and 15.1 MJ, respectively, and a decrease in Land Use (LU) of 8.65 m2.