Seeds containing high amount of oil (like sunflower or rapeseed) are generally first mechanically pressed to extract a portion of crude oil (pre-pressing); the press cake is then subjected to solvent extraction. In some cases (rapeseed), the full pressing is an option.
How is crude oil produced in a soybean crushing plant?
The crude oil is usually water degummed in the crushing plant which generates an additional flow, consisting of gums (or lecithin). Table 1 presents the main quality parameters (optimal contents) of the major products from soybean crushing.
What are the benefits of soybean hulls?
On top of the better quality of final product for some seed qualities, it brought savings of about 20 to 25?kg steam/t of seed. As lateral benefit, the residual oil in hulls is also improved, bringing down the oil in hull from almost 2% to 1% (for soybean).
What is the residual oil content of soybean meal?
It is critical to avoid the presence of cracks in order to get reasonable residual oil content in the meal. In a modern and efficient extraction plant (Fig. 9), a residual oil content ¡Ü?0.5% for soybean meal is expected.