Material guide · 157
Material guide: folded sweet orange oil — 122 suppliers, more than the whole oil, and one record covering 5-fold to 50-fold
· 18 min read
CAS 8008-57-9, 122 suppliers, more than sweet orange whole oil's 99 and the most-supplied citrus record in this database. Its solubility field opens the market up by accident: Orange Oil 5 X, 10 X, 20 X, Italian 5 Fold and 10 Fold, Folded 5 fold to 20 fold, and Orange Essential Oil 50 Fold. One record covers every product from 5-fold to 50-fold. And the fold factor has an arithmetic ceiling: if terpenes are a fraction f of the crude oil, removing only terpenes cannot exceed 1/(1-f). At 90% terpenes that is 10-fold, at 95% it is 20-fold, and a 50-fold oil requires a crude oil that was 98% terpenes. Its registered optical rotation is +91 to +78, while fully deterpenated sweet orange reads +11 to +24, so that interval plainly cannot cover a 50-fold product. Its substantivity field is empty, where the whole oil reads 140 hours and the terpeneless one 212.
About a 4 minute read.
The short version
- Name: sweet orange peel oil folded, CAS 8008-57-9, 122 suppliers
- More than sweet orange whole oil's 99. The most-supplied citrus record here is a folded oil, not a crude one
- Odour type citrus; odour: sweet, fresh, juicy, tart, orange peel
- Optical rotation +91.00 to +78.00, specific gravity 0.854–0.865, shelf life 12 months
- Its substantivity field is empty, where the whole oil reads 140 hours and terpeneless reads 212
- 146 formulas in the corpus (sweet orange merged) at a median dose of 3.11%
- Its solubility field lists market products from 5-fold to 50-fold
The best-supplied sweet orange oil is not the crude one
| Record | Suppliers | Optical rotation | Substantivity | Appearance |
|---|---|---|---|---|
| sweet orange peel oil folded | 122 | +91 ~ +78 | (empty) | dark brownish orange |
| sweet orange peel oil | 99 | +94 ~ +99 | 140 h | yellow orange to deep orange |
| sweet orange peel oil terpeneless | 31 | +11 ~ +24 | 212 h | colourless to yellow |
The folded oil has more suppliers than the crude. That is worth noticing on its own: orange oil is among the highest-volume essential oils in the world, and the market's main form is concentrated rather than as-pressed.
The reason is in that paragraph of notes from last round: citrus oils
are over 90% terpenes, and those terpenes contribute almost no odour, do not dissolve in alcohol,
and oxidise. Shipping and storing them is pure waste.
The solubility field opens the market up
The solubility field is supposed to list solvents, but it also collects suppliers' sample
information, which turns it accidentally into a market listing:
Orange Oil 10 X; Orange Oil 20 X; Orange Oil 5 X; Orange Oil Italian 5 Fold, 10 Fold; Orange Oil Folded 5 fold to 20 fold; Orange Essential Oil 50 Fold
One database record covering every product from 5-fold to 50-fold.
"5-fold" means the volume was concentrated to a fifth. What you buy is not something added; it is something removed.
The fold factor has an arithmetic ceiling
I have not seen this stated plainly anywhere, and it is only a division.
Let terpenes be a fraction f of the crude oil, and let folding remove only terpenes. Removing all of them leaves 1 − f of the volume, so the fold factor cannot exceed 1/(1 − f):
| Terpene fraction of the crude | Ceiling on terpene-removal folding |
|---|---|
| 90% | 10-fold |
| 95% | 20-fold |
| 98% | 50-fold |
The database says citrus oils are "more than 90% terpenes". So working backwards from the market's "50 Fold", the crude oil must have been 98% terpenes. Sweet orange really is the highest-limonene citrus, so 98% is possible, but it sits against the ceiling.
The practical reading: the fold factor is not a marketing number. It tells you the terpene content of the crude oil it came from. An orange oil sold as 20-fold implies its crude was at least 95% terpenes.
That rotation range cannot cover the product line
optical_rotation reads +91.00 to +78.00.
Against last round's ladder:
| Optical rotation | |
|---|---|
| Sweet orange whole oil | +94 ~ +99 |
| Folded (this record) | +78 ~ +91 |
| Sweet orange terpeneless | +11 ~ +24 |
+78 to +91 sits only slightly below the whole oil. That can describe a 5-fold oil, but a 20-fold or 50-fold oil is close to deterpenated and should read down in the twenties.
A thirteen-degree interval cannot cover a product line running from 5-fold to 50-fold.
This is not the database getting something wrong. It is one record being asked to describe a whole spectrum, the same problem I hit with ylang's four grades. The granularity is short. The difference is that ylang at least splits into four records; folded orange oil is one.
In practice: ask for the fold factor and measure the rotation. If a seller says 20-fold and you read +85, it is not 20-fold.
The colour goes both ways
The three records' appearance fields:
| Appearance | |
|---|---|
| Whole oil | yellow orange to deep orange |
| Folded | dark brownish orange |
| Terpeneless | colourless to yellow |
The folded oil is darker than the crude and the terpeneless one is lighter.
One reading that works: the processes run in different directions. Folding distils the terpenes off overhead, leaving the coloured constituents to concentrate in the pot, so it darkens. If deterpenation distils the oxygenated fraction over instead, the pigments stay in the residue and the product comes out colourless.
That is my inference; the database says nothing. But the two colour fields do move in opposite directions, and this account is consistent with them.
The substantivity field is empty
The whole oil reads 140 hours, the terpeneless one 212, and the record between them has no value.
By the relationship I computed it should fall between the two, approaching 212 as the fold factor rises. But that is interpolation, not measurement.
That is this record's second granularity problem: what it needs is not one number but a curve against fold factor.
In formulas
Sweet orange merged gives 146 formulas at a median dose of 3.11%, quartiles 2.00–6.00%, maximum 73.2%.
Most frequent company: dipg (68), linalool (63), benzyl acetate (53), coumarin (40), alpha-hexyl cinnamaldehyde (38), hedione (36), lilial (36).
But the corpus almost always writes the unqualified orange oil (52), orange oil florida (20) or
orange oil brazil (17). Only orange peel oil 5 fold, 7 fold and 10 fold, one formula each,
name a fold factor.
Same as with lemon: people writing formulas do not write specifications.
Safety and regulatory
- FEMA GRAS, FEMA 2825
- Oral LD50 > 5,000 mg/kg (rat)
- Shelf life 12 months, as short as lemon oil's, because limonene autoxidises
- The
notesfield mentions it is used in pharmaceuticals for fragrance and flavour
Oyedeji and colleagues measured sweet orange peel oil and its individual constituents against two stored-product pests in 2020 (PMID 32711776), and Hong and colleagues measured the enantiomeric composition of several citrus species by MDGC-MS in 2017 (PMID 28444796).
What this doesn't establish
- The ceiling arithmetic assumes folding removes only terpenes. Real processes lose some oxygenated material too, which would push the real ceiling lower. What I computed is an upper bound.
- "50-fold implies a 98% terpene crude" is that arithmetic run backwards, not a measurement. That product's definition of "50-fold" may also differ from volume concentration.
- The colour section is my inference. The database gave three
appearancevalues and said nothing about process direction. - I did not measure any rotation. The claim that +78 to +91 cannot cover 50-fold is inferred from the terpeneless record's +11 to +24.
- I did not interpolate the substantivity, and would not recommend it. I have written that this field should be read as a ranking.
- The 146-formula merge excludes neroli and bitter orange, which are different materials.