High-value products from food waste: An environmental and socio-economic assessment

The use of food waste as feedstock in the manufacture of high-value products is considered a promising avenue for achieving (bio)circular economy goals. The use of residual biomass helps decrease fossil fuel dependency whilst simultaneously reducing the demand for additional biomass resource. Despite the interest in exploiting food waste in high-value product manufacturing, few studies assess the sustainability of such applications. In this study a life cycle assessment, a conventional and a societal life cycle costing were performed to evaluate the impacts of five standalone case studies based on wet animal feed, protein-concentrated animal feed, lactic, polylactic and succinic acid production from food waste. The results showed that animal feed production decreased global warming and socio-economic potential impacts relative to conventional feed products. Biochemical manufacturing incurred higher impacts from both the environmental and the socio-economic perspectives. These technologies are characterised by a low technology readiness level that should be taken into account when interpreting and using the results. Precisely for this reason, extensive uncertainty and sensitivity analyses were performed for each biochemical production technology to establish the hotspots, which were identified in steam and ancillary materials consumption, and feedstock-to-product yield. This suggests where to centre future optimisation and research efforts to achieve sustainable competitive technologies. Through this exercise, the study aims to shed light on the relevance of applying life cycle assessment and costing in the design and early (bio)technology development phases.