Influence of camelina seed Oil-Bodies release parameters in the development of a low environmental impact integrated oilseed biorefinery scheme

Camelina is a seed under-exploited despite its clear agronomic advantages (resistance to pests, low input requirements, plant cover, etc.). Its most valuable fraction is its oil, rich in polyunsaturated fatty acids. It is stored in the form of oil-bodies (OB) that naturally protect it against oxidation and could effectively vectorize it for functional food, cosmetic or pharmaceutical applications. The work presented here concerns the study and the lifting of scientific and technological barriers for the release of these (OBs) in a circular economy context. The process developed starts by removing mucilage, representing 6% of the seed weight. The synergistic use of ultrasound and hydrodynamic forces shortens the duration of this stage and limits protein diffusion. The following steps are a high-shear grinding followed by a high-pressure homogenization to destructurate the seeds and release (OBs) in water. The recovery of the different fractions is carried out by centrifugation at low temperature giving rise to three valorizable products: i) an emulsion rich in (OBs), ii) a mineralized aqueous concentrate rich in water-soluble proteins, iii) a mucilage-free sedimentary pellet rich in fibers and proteins. pH could be adjusted in order to control (OB)-(OB) and (OB)-Protein interactions. A basic pH and four homogenization cycles carried out with increasing pressures allowed to increase the release and recovery of (OBs) from the seed with a lipid yield of more than 63%. A gate-to-gate life cycle assessment indicated that pH adjustments and pressure have a low contribution to environmental impacts. These results show key parameters for the release and valorisation of native OBs from camelina seeds that can still be exploited to further improve OB yield.