Page 128 - EER-2-2

Explora: Environment
and Resource Microemulsion-based canola oil extraction

larger oil phase in formulation #13 compared to #14 (which still be improved by optimizing the premix formulation.
contained more lecithin – 1.80 g vs. 0.72 g) when de-oiled Using a “one factor at a time” approach and a constant
CSM was used can be explained. Overall, formulations #13, CPC: premix ratio (1:3), no free oil phase was observed
14, 17, and 18 recovered nearly 55%, 34%, 16%, and 19% when other premixes (#5, 6, 7, and 8) were tested (Table 3).
of the initial oil, respectively. However, when considering On the other hand, in formulations # 1, 2, and 3, a free oil
part of the recovered oil as coming from lecithin itself, it phase was clearly visible and transparent, but the size of
can be concluded that the actual oil extraction capacity the oil phase in formulation #3 was visually larger than in
of the Epikuron 135F-based ME was lower than 55 and formulations #1 and #2. Formulation #4 turned into a thick
34%. Despite the differences in terms of CSM type and gel and, therefore, was not used during the optimization
the lecithin utilized in the present study, the oil recovery process.
rate (55%) was quite comparable to the ~62% reported in
previous studies. 13,14 The high extraction yield reported in According to these formulation tests, it can be concluded
those studies 13,14 can likely be attributed to the oil content of that the optimized premix formulations should have
the lecithin, which was partially purified by the researchers. high water content (~77%) and co-surfactant: surfactant
Based on their chromatographic analysis, the oil content ratios of 4:1 or 5:1 to perform optimally. The fibrous
13
of lecithin was ~19%, which could contribute significantly and collapsed structure of the CPC requires high water
to the overall oil recovery, especially considering the high content to facilitate the mobility of surfactant molecules
concentration of lecithin utilized in the extraction process. and the diffusion of the ME premix, which is necessary
to release the entrapped oils. The highest estimated oil
Based on the findings from the CSM experiments, the extraction rate was ~50%; however, only a small portion
next set of experiments was conducted on CPC using pure of that oil was in the free oil phase, while the remainder
lecithin (Epikuron 170) and various premix formulations was emulsified and would require demulsification to
(Table 3). Using a constant CPC: premix ratio (1:3), 5 g of release the oil. Despite the potential capability of pure
CPC was mixed with 15 g of premix #1 (Table 3), heated lecithin (surfactant) in combination with 1-propanol
(60°C, 30 min), and centrifuged (10,000 g, 10 min). (co-surfactant), the high costs of lecithin and 1-propanol,
Interestingly, pure lecithin showed its ability to recover the need for demulsification, the partial dissolution of
part of the oil from CPC. Therefore, the pellets from this CPC’s soluble proteins, lipoproteins, and polysaccharides,
extraction cycle were mixed with 10 g of fresh premix (#1, as well as the potential residual lecithin in the de-oiled
Table 3), then heated and centrifuged again. Surprisingly, pellets (Figure 4), make this approach unsuitable as a
there was almost no visible oil phase after centrifugation. recommended technique for industrial applications. It is
The pellets from this second extraction cycle were mixed worth noting that the extraction efficacy could potentially
with another 10 g of fresh premix and treated as described
above, but no oil was recovered at this stage either. be slightly improved by optimizing heating conditions,
These observations suggest that, at least under the stated utilizing a smaller size range of CPC particles, and/or
conditions, only part of the oil can be recovered as free oil, adjusting CPC: premix ratio, if necessary.
and multiple extractions did not significantly improve the Based on numerous trials, it was revealed that ethanol
recovery. However, it was assumed that the efficacy could could also be used instead of 1-propanol; however, the
Table 3. Formulation of lecithin (Epikuron 170)‑based microemulsion premix for oil extraction from canola press cake (CPC)

c
# Premix CPC (g) CPC: premix d Total Heated
1‑PrO (g) Lecithin (g) 1‑PrOH: lec Water (g) (1‑PrOH: Total ratio (w/w) weight (g) (60°C, 30 min)
b
a
Ratio (w/w) lec): water weight (g)
ratio (w/w)
1 17.78 2.22 8:1 80.00 1.00:4.00 100.00 5.00 1:3 20.00 Yes
2 17.78 4.44 4:1 77.78 1.00:3.50 100.00 5.00 1:3 20.00 Yes
3 18.00 4.50 4:1 77.50 1.00:3.44 100.00 5.00 1:3 20.00 Yes
4 12.00 8.00 3:2 80.00 1.00:4.00 100.00 5.00 1:3 20.00 Yes
5 18.50 7.50 5:2 74.00 1.00:2.85 100.00 5.00 1:3 20.00 Yes
6 33.33 16.66 2:1 50.00 1.00:1.00 100.00 5.00 1:3 20.00 Yes
7 30.00 20.00 3:2 50.00 1.00:1.00 100.00 5.00 1:3 20.00 Yes
8 48.00 32.00 3:2 20.00 4.00:1.00 100.00 5.00 1:3 20.00 Yes
Notes: 1-PrOH: 1-propanol; Lec: Lecithin; CPC: Canola press cake; dpremix: Mixture of 1-propanol, lecithin, and water.
b
c
a
Volume 2 Issue 2 (2025) 7 doi: 10.36922/eer.6562