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Quick answer
FSG (First Special Grade) is the fully refined, palest, lowest-acid-value castor oil — the premium base grade for uses where the oil's colour and consistency show in the finished product. FPD (First Pressed Degummed) is pressed and degummed only: clean and stable with the same castor chemistry, but a slightly deeper colour, sold as a cost-effective industrial feedstock. Choose FSG when appearance or a broadly accepted premium grade matters; choose FPD when you are feeding a downstream process where ultra-pale colour is not essential and price is.
Both grades come from the same castor seed and share the same underlying chemistry — the difference is how far each is refined. FSG goes all the way through refining and bleaching to reach the palest, cleanest result. FPD stops after degumming. That single choice drives their colour, acid value, price and best-fit uses. If you only remember one thing: FSG is bought for its appearance and broad acceptance, FPD for its value as a feedstock.
First Special Grade is the flagship base grade of castor oil. It is fully refined to a pale colour with a low acid value and tight, consistent quality. Because it looks clean and behaves predictably, it is the default choice for buyers whose end product would reveal any colour in the raw oil, and it is widely specified across cosmetics, pharmaceuticals and premium industrial uses. For a premium-vs-economy comparison against the lowest grade, see FSG vs Commercial Grade castor oil.
First Pressed Degummed is a mid-tier grade: pressed, then degummed to remove gums and phospholipids for stability and clarity — but not taken through full bleaching. The result keeps the complete castor chemistry with a slightly deeper natural colour, at a lower price than FSG. It is the practical choice as an industrial feedstock — for derivatives, lubricants and coatings — where reliable chemistry matters more than an ultra-pale appearance. Full detail is in our FPD castor oil guide.
| Factor | FSG (First Special Grade) | FPD (First Pressed Degummed) |
|---|---|---|
| Refining | Fully refined & bleached | Pressed + degummed only |
| Colour (Gardner) | ~1–3 (palest) | ~3–5 (deeper) |
| Acid value | ~1.5–2.0 mg KOH/g | ~2.0–3.0 mg KOH/g |
| Hydroxyl value | ~160–168 | ~160–168 |
| Iodine value | ~82–90 | ~82–90 |
| Relative cost | Higher | More economical |
| Best for | Colour-sensitive, premium, broad use | Industrial feedstock & formulations |
Notice the hydroxyl and iodine values are the same — the reactive chemistry does not change between the two. What differs is colour, acid value and price.
If you are weighing the whole range rather than just these two, our grade selection guide lines up FSG, FPD, PPG, commercial and cold-pressed side by side.
FSG (First Special Grade) is fully refined and bleached to the palest colour with the lowest acid value. FPD (First Pressed Degummed) is pressed and degummed only, giving a slightly deeper colour at a lower price. The underlying chemistry is the same.
Not universally — it is better where colour and broad acceptance matter, such as cosmetics and premium uses. For industrial feedstock use, FPD delivers the same chemistry more economically.
No. Both share the same ricinoleic-acid chemistry, with similar hydroxyl and iodine values. They differ mainly in colour, acid value and degree of refining.
FPD is generally more economical because it involves less refining. FSG commands a premium for its paler colour and broader acceptance.
