Valorization of Soy Sauce Residue: Analyzing Supercritical CO2 Extraction with Economic and Environmental Perspectives

Abstract The objective of this work was to explore the use of supercritical carbon dioxide (SCCO2) extraction to obtain bioactive compounds from soy sauce residue. The yields obtained by SCCO2 extraction varied between 15.93 and 20.51%. There was a clear effect of pressure on the extract yields, as opposed to temperature variation and the addition of a cosolvent. The extracts showed slightly active antioxidant activity. The economic evaluation showed that SCCO2 extraction of soy sauce residue can be considered profitable in three of the four experimental conditions. Among the ones that had a very good economic return, the condition that minimizes the cumulative global temperature potential was 200 bar and 40 °C. The use of this optimized condition would reduce the amount of waste disposed of or treated and produce high-quality extracts that could be used in the pharmaceutical, food, and cosmetics industries. All these actions would make the shoyu sauce process more sustainable.