Solvent Solutions: Comparing Extraction Methods for Edible Oils and Proteins in a Changing Regulatory Landscape. Part 7: Overall comparison between solvent solutions

Oilseeds extraction of oils requires the use of a processing aid : a solvent. This seventh article on the comparison of solvents potentially capable of replacing hexane presents a multi-criteria analysis, systematically revisiting aspects from previous investigations. The methodology addresses the problem’s complexity by aggregating different dimensions representative of each criterion, resulting in a nuanced ranking approach. The comprehensive study examined critical dimensions including solvent extractive efficacy, operational safety, explosion risk, toxicity to workers, environmental impact, process modifications, energy consumption, effects on products quality, residual toxicity, technology readiness level, and economic feasibility. From a technical standpoint, hexane today remains the most efficient solvent for oilseed crushers. Dichloromethane may be a viable alternative due to its non-explosive nature, though its toxicity concerns are significant. 2-methyloxolane is the subject of ongoing research and development investments, which may ultimately establish it as a credible alternative solution. Different stakeholders present varied perspectives on solvent replacement. For worker safety, isopropanol and ethanol are preferable options. Environmental advocates may favor ethyl acetate because of its lower energy requirements during processing. Regarding food safety, both ethanol and ethyl acetate are generally regarded as acceptable solvents. Public authorities, for their part, must balance what is desirable with what is feasible, in a multi-criteria framework of balancing safety, toxicity, environmental impact, availability, and cost on a global scale.