INFORM April 2026

SOLVENT EXTRACTION INFORM 35

stabilization phase may appear as a limitation, it must be considered in the context of continuous operation, where extraction units typically run for extended periods. Once steady state was reached, 2-MeOx achieved oil concentrations in the miscella higher than those obtained with hexane, confirming its strong extraction capacity under stabilized conditions. These observations highlight the importance of evaluating transient phases in addition to steady-state performance, as laboratory-scale experiments rarely capture start-up effects that can be decisive for industrial process control and operational robustness. From an operational standpoint, 2-MeOx’s affinity for water also makes solvent extraction less sensitive to variability in raw material preparation. Variations in seed or presscake moisture, flake thickness, or matrix structure has less impact on extraction performance. Combined with its higher boiling point compared to hexane, this contributes to more robust industrial operation, shifting part of the process focus from raw material preparation to solvent water management. WATER MANAGEMENT When using Ecomeo, solvent water content is an influential operating parameter. Due to its partial miscibility with water, 2-methyloxolane can carry up to 4.5 percent water, significantly modifying its extraction parameters.

Increasing solvent hydration raises its polarity, enhancing the extraction of polar compounds such as phospholipids, tocopherols, and polyphenols. These conditions reduced the residual oil content (ROC) in the meal. For example, while hexane extracted meal showed a ROC close to two percent, hydrated 2-MeOx achieved values around 0.5 percent. This increased extraction efficiency comes with trade offs. Water introduced with the solvent tends to concentrate in the meal after extraction, increasing solvent retention and drying requirements. The higher water content negatively affected protein quality indicators, such as protein dispersibility index (PDI). Conversely, maintaining a solvent water content of one percent or less improved protein functionality compared to hexane and even to the initial raw material itself, possibly due to water activity effects within the extractor. At the same time, extraction performance remained favourable, with meal ROC close to 1 percent. These results demonstrate that optimizing 2-MeOx extraction relies on precise water management, a parameter absent from conventional hexane-based process design. IMPLICATIONS FOR INDUSTRIAL ECO-EXTRACTION Taken together, the results of this study and other developments at Ecoxtract

indicate that replacing hexane with 2-methyloxolane cannot be considered a simple drop-in substitution. Although 2-MeOx can be retrofitted into existing hexane extraction units—and have already been implemented—the transition requires process adaptation and a learning phase for R&D and engineering teams. Working with a different solvent means accounting for new interactions between solvent, matrix, and products, as well as revised operational strategies. Looking ahead, we foresee possible greenfield extraction processes specifically designed for Ecomeo with dedicated thermal integration and in-line monitoring of solvent water content. In such a configuration, preliminary internal work suggests that operating with hydrated 2-MeOx require lower energy than conventional hexane based processes. These perspectives highlight how solvent-specific process design may open new avenues for process optimization and product development beyond direct substitution. Also, beyond solvent substitution, it illustrates how solvent-specific process design can contribute to the broader transition toward more sustainable and resilient extraction technologies.

For hyperlinks to references visit inform.aocs.org

Julie Ducreux is the Technical Manager of Ecoxtract. She can be contacted at julie.ducreux@ecoxtract.com.