Seed oils energy content

Specific bound chemical energy in J per g dry mass of seeds (bars) and content of assimilates in sunflower seeds (sugars-1, total amino-acids-2, proteins-3 and oil-4) in the course of formation and seed filling. 

Fadhlullah, M., Widiyanto, N.B., et al., 2015. The potential of nyamplung Calophyllum ino-phyllum L.) seed oil as biodiesel feedstock effect of seed moisture content and particle size on oil yield. In Bakar, R.B.A., Froome, C. (Eds.), 2nd International Conference on Sustainable Energy Engineering and Application, 68. Elsevier Science B.V., Amsterdam, pp. 177-185. 

Flaking ruptures the cell walls, which allows some of the oil to be separated from the seed residue by simple pressing. Further, the oil retained in the seed residue can now be more efficiently leached out in subsequent solvent extraction of the press cake with hexane. Properly flaked material is more easily treated in the subsequent cooking operation and requires less mechanical energy in pressing. It is essential that the residual oil content in the meal be low for this operation to be economical. 

In plants, triacylglycerols constitute an important energy reserve in fruits and seeds. Because these molecules contain relatively large amounts of unsaturated fatty acids (e.g., oleic and linoleic), they are referred to as plant oils. Seeds rich in oil include peanut, com, palm, safflower, and soybean. Avocados and olives are fruits with a high oil content. 

It is desirable to remove the hull (seed coat) that covers the soybean cotyledon or meat. Soybean hulls contain much less oil and protein than do the meats. Soybean hulls account for about 8% of the bean dry matter but contain less than 1% lipid. Removing the hull reduces the amount of material that must be further processed, thus increasing downstream plant capacity and reducing energy consumption per unit processed. However, removing the hull is usually done to raise the protein level of the meal. The protein content of soybean meal increases by about 4 percentage points... 

The principal mechanism by which fatty acids are broken down in plants is P-oxidation (Fig. 2.11) (Kindi, 1987). On germination, seeds with high oil content form glyoxysomes that contain the enzymes of P-oxidation. In this process, much of the energy stored in the lipids is converted to acetyl-CoA and is trapped in the thioester bond. Acetyl-CoA then enters the tricarboxylic acid cycle (TCA). P-Oxidation in plants appears to be identical to that of animals. 

---