Barriers to the release of flaxseed oil bodies and ways of overcoming them

Abstract

-The outermost mucilaginous layer of the seed is a major, valuable component of flaxseed, but it induces a rapid thickening of the medium when the seeds are immersed in water, reducing the efficiency of oil body extraction. Ultrasound can be used to extract this mucilage rapidly before the seeds are ground in water. This makes it possible to extract the oil bodies as an emulsion, with the proteins present acting as dispersing and stabilizing agents. This emulsion is a thick fluid displaying shear-thinning and predominantly elastic behavior. This phase can be valorized directly due to its high concentration in polyunsaturated fatty acids, high content of valuable sterols, and high arginine content of its proteins.

Low‐Field Nuclear Magnetic Resonance Time Domain Characterization of Polyunsaturated Fatty Acid–Rich Linseed and Fish Oil Emulsions during Thermal Air Oxidation

“…This structural organization contains polar head groups on the surface of the OB in contact with water, while the hydrophobic tails are inside and away from the aqueous matrix. The OB's interfacial surface coating layer contains the linseed (LS) phospholipids and amphiphilic proteins such as oleosins and residual linseed mucilage components that together stabilize the OB (Fabre et al, 2015; Goyal et al, 2015). Thus, LSE chemical and morphological structures are OB vesicles with a multicomponent amphiphilic surface and lipophilic core of encapsulated PUFA‐rich oil.…”

Low field NMR Time Domain (TD) Characterization of PUFA-rich Linseed and Fish Oil Emulsions During Thermal Air Oxidation

“…This structural organization contains polar head groups forming the outside as the surface of the oil bodies in contact with water, while the hydrophobic tails are inside and away from the aqueous matrix. The OB's interfacial surface coating layer contains the LS's phospholipids and amphiphilic proteins such as oleosins and residual linseed mucilage components, that together stabilize the OB (Goyal et al, 2015;Fabre et al, 2015). Thus LSE chemical and morphological structures are oil body vesicles with a multicomponent amphiphilic surface and lipophilic core of encapsulated PUFA-rich oil…”

“…An alternative relatively novel approach to PUFA encapsulation is based on natural seed oil bodies (OB), that can spontaneously, under external force, organize in a water matrix to form emulsions (Goyal et al, 2015). Linseed is an excellent source of such oil body emulsion products (Fabre et al 2015).…”

Oil body extraction from oleo-proteaginous seeds and conservation of valuable native compounds

“…For flaxseed, values are generally found between 4 and 5 (Dev and Quensel, 1988;Hellebois et al, 2021;Lan et al, 2020;Malik and Saini, 2018;Sosulski and Bakal, 1969;Tirgar et al, 2017;Vassel and Nesbitt, 1945) even if some authors found lower (3-3.5) (Wanasundara and Shahidi, 1994) or higher (4.7-5.6) values (Chung et al, 2005). Concerning membranous proteins, an isoelectric point around 4.0 (Fabre et al, 2015a) was found.…”

“…However, with denaturation of membranous proteins at high pH and the solubilization of extraneous proteins, a thinning of the interfacial zones occurs and possibly a decrease of the interactions oleosins/phospholipids. The steric hindrance is lowered and coalescence phenomenon can be enhanced (Fabre et al, 2015a;Nikiforidis and Kiosseoglou, 2009). The conservation of valuable compounds of the seeds as triglycerides, phospholipids, tocopherols and sterols in the extracted oil bodies and the conservation of their structure is therefore a challenge that involves the choice of mechanical and chemical solutions adapted to the studied matrixes.…”