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Explora: Environment
and Resource Microemulsion-based canola oil extraction

was observed except for very small droplets, but three recover only a small fraction of the CPC oil. In the presence
distinct phases were identified (Figure 1). It was expected of organic solvents (1-propanol or ethanol), approximately
that under alkaline conditions, the oil, which was already 27% of the CPC oil was extracted. Surprisingly, by
entrapped or covered by proteins or phospholipids, could increasing the pH of the dispersions (~10.0), Tween 80
be more easily released, likely due to the denaturation of was able to release nearly 40 – 50% of the oil, using a
the existing proteins. By checking the oil content of the very low concentration and mild thermal treatment. It is
pellets, it was found that nearly 40% of the oil content of expected that under optimized conditions, the extraction
CPC was extracted using the Tween 80 premix (Tween 80 rate can be further improved. Due to the insolubility of
= 0.15%, CPC: premix ratio = 1:4, pH = 10.0). Previous Spans, particularly Span 80, it is not recommended for use
reports have indicated that with increasing alkaline either individually or in combination with Tweens for oil
concentration (0.02 – 0.08 M), temperature (20 – 55°C), extraction purposes.
and decreasing particle size of defatted CPC, the protein
yield and separation rate increased. Therefore, it can be Acknowledgments
28
speculated that under alkaline conditions, the proteins The authors gratefully acknowledge the financial support
or phospholipid layers, which previously covered the oil of the sponsors of the Canola Cluster Project.
droplets, could be solubilized, denatured, and displaced by
the Tween molecules. Such displacement is theoretically Funding
likely, as the molecular size of Tweens is much smaller Financial support was provided by Canola Council of
29
than that of proteins, giving them a very low surface load. Canada, Alberta Canola, SaskCanola and Manitoba
Recent studies 23,24 have investigated the demulsifying Canola Growers Association through the AgriScience
functions of Tweens (20 and 80) on recovering peanut and Program (Canola Research Cluster) under the Canadian
rapeseed oil. They claimed that Tweens were capable of Agricultural Partnership.
de-emulsification and that Tween 20 at 1.2% and alkaline
pH recovered 72% and 51% of the oil content of peanut Conflict of interest
paste and crushed rapeseeds, respectively.
The authors declare that there are no conflicts of interest
Based on our observations, Tweens 20 and 80, under regarding the publication of this article. They further
the above-mentioned conditions, potentially released declare that they have no known competing financial
about 40% of CPC’s remaining oil in an emulsified form. interests or personal relationships that could have appeared
Compared to other conditions discussed in the present to influence the work reported in this paper.
study, it seems that alkalization is, by far, the most feasible
approach to extracting the majority of the remaining Author contributions
oil from CPC. It is likely that optimizing pH, Tween Conceptualization: All authors
concentration, the thermal process, CPC: Tween solution Funding acquisition: Martin G. Scanlon
ratio, and CPC particle size could further improve the Investigation: Soleiman Abbasi
oil extraction rate. However, the de-emulsification of the
separated liquid phase to release the oil phase remains a Methodology: Soleiman Abbasi
major challenge that needs to be addressed. Moreover, Project administration: Martin G. Scanlon
due to the increased protein solubility under alkaline Supervision: Martin G. Scanlon
pH, the quantity and quality of the protein in the pellet Validation: Soleiman Abbasi
should also be investigated. These concerns, along with the Writing – original draft: Soleiman Abbasi
applicability of Tweens for the extraction of canola seed oil Writing – review & editing: All authors
(both cooked and uncooked) under alkaline pH, have been Ethics approval and consent to participate
discussed in another report. 24
Not applicable.
4. Conclusion Consent for publication
The capabilities of different lecithin types (partially purified
and pure), Tween 80 and Span 80, on recovering the Not applicable.
remaining oil from CPC were investigated. Based on the Availability of data
observations, lecithin alone was unable to recover any oil.
However, when mixed in an optimal ratio with 1-propanol The datasets generated and/or analyzed during the
or ethanol, part of the CPC oil was released as free oil. current study are available from the corresponding author
Regarding Tween 80, under natural pH, it was able to (Soleiman Abbasi) upon request.

Volume 2 Issue 2 (2025) 9 doi: 10.36922/eer.6562