Cold-pressed camelina oil deacidification using short path molecular distillation: An optimization study and comparison with conventional techniques

In this research, the impact of short-path molecular distillation (SPMD), as a green and solventless method, in the deacidification of cold-pressed camelina oil (CPCO) was investigated. Physical refining of crude vegetable oils with high free fatty acids (FFA) content leads to healthier oils, preventing excessive oil loss and minimizing waste production. Using central composite design approach-based response surface methodology (RSM-CCD) analysis, optimized SPMD process parameters were determined and verified. The investigated factors were evaporation temperature (ET: 160–200 °C), feed flow rate (Q: 0.50–3.00 mL/min), and feed temperature (FT: 80–120 °C). Deacidification efficiency (DE) and distillate-to-feed mass ratio (D/F) were selected as the separation performance responses. In addition, to monitor the qualitative effect of the SPMD, peroxide value (PV) and total polar compounds (PC) were designated as the complementary responses. The optimized values for ET, Q, and FT could be considered to be 200 °C, 0.50 mL/min, and 100 °C, respectively. At the optimum operating conditions, DE, D/F, PV, and PC were determined as 63.27 %, 5.78 %, 24.5 meq/kg, and 11.4 wt%, respectively. The SPMD were compared with conventional fractional distillation (FD), steam stripping distillation (SSD), and alkali neutralization (AN). It was validated that SPMD could efficiently and sustainably deacidify the CPCO. Additionally, the effect of two successive SPMD treatments at the optimum conditions was also examined. By double deacidification, the DE, D/F, PV, and PC values were 74.34 %, 6.88 %, 27.6 meq/kg, and 16.0 wt%, respectively.