Abstract
Upcycling side- and waste streams can expand nutrient availability, reduce waste, and improve value retention. However, changes of product utilisation can also cause changes to environmental burdens, nutrient flows and market dynamics. Using life cycle assessments (LCA) gives insights into environmental footprints, however, results are sensitive to goal and scope choices like intended context, audience, functional unit, system boundaries and substitution or allocation approaches.
An attributional LCA of two upcycled products - herring oil and collagen from filleting cut-offs, was assessed for their life cycle inventory. Using three goal-statement paradigms (consumer, producer and governmental), the implications of functional units, allocations, and substitution modeling was assessed. Evaluating the benefits and challenges that upcycling can cause dependent on methodological choices. Using these findings, a material flow analysis (MFA) of herring landed in Norway was integrated with the LCA results to create a scenario analysis to assess the implications of reallocating herring cut-offs from salmon feed to upcycled food alternatives. Tracking nutrient provision, environmental footprints, product quantities, and purchase-cost proxies.