One US gallon of soybean oil weighs approximately 7.7 lb (3.5 kg). Soybeans typically hold 18–20% oil by weight (industry range) — the lowest of the major oilseeds. Even at full theoretical recovery, you would need about 40 lb of soybeans per gallon; with realistic screw-press recovery, working mills plan on roughly 45–55 lb (20–25 kg) per gallon.
Solvent-extraction plants recover more oil per bean, but at small and mid scale, mechanical pressing — ideally with extrusion beforehand — is the practical route.
The cake left after pressing is high-protein soybean meal, one of the world's most traded feed ingredients. For most press operations, meal revenue equals or exceeds oil revenue — pressing soybeans is effectively a two-product business. Dehulling before pressing raises meal protein and meal price; see the soybean pretreatment guide for the full line.
Three levers: crack the beans properly before conditioning, condition hot right before the press, and consider an extruder ahead of the press — extrusion ruptures cells mechanically and is the single biggest press-yield upgrade available for soybeans. Equipment for each stage is covered under seed preparation equipment.
A 60 lb bushel at 18–20% oil content carries roughly 11–12 lb of oil in theory; mechanical pressing recovers part of that, solvent extraction nearly all. That is about 1.4 gallons theoretical, less in practice on a press.
Composition: soybeans are roughly 35-40% protein and only 18–20% oil, while shelled peanuts are 40–50% oil. Soybean is fundamentally a protein crop with oil as the co-product.
Depends on local supply and what sells: peanuts give far more oil per ton, soybeans give valuable high-protein meal. Many mills run both seasonally on the same press line with different pretreatment settings.
SinoOil engineers size the right pretreatment equipment for your capacity — free plant design included.
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