Environmental Sustainability Assessment of a Filtration-Diafiltration Strategy for Recovering Savory Compounds from Mussel Cooking Water

Abstract

Global seafood production and consumption have increased in recent years, leading to a significant rise in side streams. Process waters are often disposed as wastewater, causing difficulties for industries in meeting the discharge standards. This is particularly relevant to the mussel processing industry, where one-third of the raw material ends up as high-organic content effluent. This study aims to optimize a nanofiltration-diafiltration (NF-DF) strategy to recover valuable savory compounds from mussel cooking water, to reduce the effluent organic pollution, and to evaluate its environmental sustainability using Life Cycle Assessment. Pilot trials lead to a configuration, combining a volumetric concentration factor of 10 in NF and 20 in DF, which achieved enhanced protein concentration (1.5-fold), amino acid concentration (5.2-fold), and COD removal (98.2\%). The environmental assessment highlighted electricity consumption during NF and DF as the primary environmental hotspot, resulting in a carbon footprint of 0.12 kg CO2 eq. kg-1 of savory compounds and water use of 0.65 m3 deprived kg-1. Prospective scenarios projected that ongoing energy system transitions could significantly reduce climate change and acidification impacts by over 75\% by 2050. The proposed NF-DF strategy enhances resource efficiency and sustainability in seafood processing by recovering high-value compounds and facilitating water reuse.