HombreOilsRare perfumery, preserved

A rose, from four molecules · the worked cases

Worked out when the page was built

The HTML equivalents of the accord’s two tools, for reading without JavaScript. Back to A rose, from four molecules.

What happens if… every single change, worked out

The same model, run when this page was built. Figures are modeled: parts, and shares per 100 parts; odour space is the share of the accord whose components carry each word; the dry-down uses the half-lives top 1.5 h, heart 6 h, base 12 h (the simulator’s site constants, not measurements); odour activity is share ÷ measured threshold, compared within one medium and unit, never across (a teaching ratio, not a measurement of this accord). This teaching accord is not a finished product and is not assessed. Nothing is for sale.

Double 2-phenylethyl alcohol (×2)
1 · Composition
2-phenylethyl alcohol 45 → 90 parts (45.0 → 62.1 per 100); the others ×0.69.
2 · Molecules
2-phenylethyl alcohol itself rises.
3 · Odour space
“floral” 45.0 → 62.1, “honey” 45.0 → 62.1, “rose” 55.0 → 37.9, “soapy” 30.0 → 20.7.
4 · Perceived character
A modeled reading, not a prediction: more “floral” and “honey” and less “rose” and “soapy”.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
2-phenylethyl alcohol (140 µg/kg in water, measured): ×1.38; lead in water (µg/kg): geraniol; 2-phenylethyl alcohol 0.01 → 0.03 of the leader.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. Components carrying “floral” go from 45.0 to 62.1 per 100 parts, because 2-phenylethyl alcohol carries it (its descriptors field).
Remove 2-phenylethyl alcohol
1 · Composition
2-phenylethyl alcohol 45 → 0 parts (45.0 → 0.0 per 100); the others ×1.82.
2 · Molecules
2-phenylethyl alcohol itself leaves.
3 · Odour space
“floral” 45.0 → 0.0, “honey” 45.0 → 0.0, “rose” 55.0 → 100.0, “soapy” 30.0 → 54.5.
4 · Perceived character
A modeled reading, not a prediction: more “rose” and “soapy” and no “floral” and “honey” left.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.8 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
2-phenylethyl alcohol (140 µg/kg in water, measured): ×0; lead in water (µg/kg): geraniol.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. 2-phenylethyl alcohol carried “floral” and no other component does on record, so the word leaves the modeled profile.
  2. 2-phenylethyl alcohol carried “honey” and no other component does on record, so the word leaves the modeled profile.
  3. Components carrying “rose” go from 55.0 to 100.0 per 100 parts, because 2-phenylethyl alcohol, which does not carry it, now takes less of the accord.
Double citronellol (×2)
1 · Composition
citronellol 30 → 60 parts (30.0 → 46.2 per 100); the others ×0.77.
2 · Molecules
citronellol itself rises.
3 · Odour space
“soapy” 30.0 → 46.2, “rose” 55.0 → 65.4, “floral” 45.0 → 34.6, “honey” 45.0 → 34.6.
4 · Perceived character
A modeled reading, not a prediction: more “soapy” and “rose” and less “floral” and “honey”.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
citronellol: no threshold on record.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. Components carrying “soapy” go from 30.0 to 46.2 per 100 parts, because citronellol carries it (its descriptors field).
Remove citronellol
1 · Composition
citronellol 30 → 0 parts (30.0 → 0.0 per 100); the others ×1.43.
2 · Molecules
citronellol itself leaves.
3 · Odour space
“soapy” 30.0 → 0.0, “floral” 45.0 → 64.3, “honey” 45.0 → 64.3, “rose” 55.0 → 35.7.
4 · Perceived character
A modeled reading, not a prediction: more “floral” and “honey”, less “rose” and no “soapy” left.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
citronellol: no threshold on record.
7 · Regulation flags
Flags leaving the accord: Regulation (EU) 2023/1545 (labelling of fragrance allergens).
Why did this change matter?
  1. It takes the “Regulation (EU) 2023/1545 (labelling of fragrance allergens)” flag (a labelling condition, extended to more fragrance allergens) off the accord: it names citronellol and no other component.
  2. citronellol carried “soapy” and no other component does on record, so the word leaves the modeled profile.
  3. Components carrying “floral” go from 45.0 to 64.3 per 100 parts, because citronellol, which does not carry it, now takes less of the accord.
Double geraniol (×2)
1 · Composition
geraniol 24.9 → 49.8 parts (24.9 → 39.9 per 100); the others ×0.80.
2 · Molecules
geraniol itself rises.
3 · Odour space
“citrus” 24.9 → 39.9, “rose” 55.0 → 64.0, “floral” 45.0 → 36.0, “honey” 45.0 → 36.0.
4 · Perceived character
A modeled reading, not a prediction: more “citrus” and “rose” and less “floral” and “honey”.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
geraniol (1.1 µg/kg in water, measured): ×1.60; lead in water (µg/kg): geraniol.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. Components carrying “citrus” go from 24.9 to 39.9 per 100 parts, because geraniol carries it (its descriptors field).
Remove geraniol
1 · Composition
geraniol 24.9 → 0 parts (24.9 → 0.0 per 100); the others ×1.33.
2 · Molecules
geraniol itself leaves.
3 · Odour space
“citrus” 24.9 → 0.0, “floral” 45.0 → 59.9, “honey” 45.0 → 59.9, “rose” 55.0 → 40.1.
4 · Perceived character
A modeled reading, not a prediction: more “floral” and “honey”, less “rose” and no “citrus” left.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
geraniol (1.1 µg/kg in water, measured): ×0; lead in water (µg/kg): geraniol → β-damascenone.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. In odour activity (share ÷ measured threshold, compared in water, µg/kg), the lead passes from geraniol to β-damascenone: a trace with a low threshold counts far beyond its share.
  2. geraniol carried “citrus” and no other component does on record, so the word leaves the modeled profile.
  3. Components carrying “floral” go from 45.0 to 59.9 per 100 parts, because geraniol, which does not carry it, now takes less of the accord.
Double β-damascenone (×2)
1 · Composition
β-damascenone 0.1 → 0.2 parts (0.1 → 0.2 per 100); the others ×1.00.
2 · Molecules
β-damascenone itself rises.
3 · Odour space
“fruity” 0.1 → 0.2, “jammy” 0.1 → 0.2.
4 · Perceived character
A modeled reading: the words on record barely move, and neither does the dry-down.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.8 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
β-damascenone (0.006 µg/kg in water, measured): ×2.00; lead in water (µg/kg): geraniol → β-damascenone.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. In odour activity (share ÷ measured threshold, compared in water, µg/kg), the lead passes from geraniol to β-damascenone, although β-damascenone is just 0.2 parts: a trace with a low threshold counts far beyond its share.
Remove β-damascenone
1 · Composition
β-damascenone 0.1 → 0 parts (0.1 → 0.0 per 100); the others ×1.00.
2 · Molecules
β-damascenone itself leaves.
3 · Odour space
“fruity” 0.1 → 0.0, “jammy” 0.1 → 0.0.
4 · Perceived character
A modeled reading, not a prediction: no “fruity” and “jammy” left.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 100.0 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
β-damascenone (0.006 µg/kg in water, measured): ×0; lead in water (µg/kg): geraniol.
7 · Regulation flags
Flags leaving the accord: IFRA Standard: Rose ketones.
Why did this change matter?
  1. It takes the “IFRA Standard: Rose ketones” flag (restriction) off the accord: it names β-damascenone and no other component.
  2. β-damascenone carried “fruity” and no other component does on record, so the word leaves the modeled profile.
  3. β-damascenone carried “jammy” and no other component does on record, so the word leaves the modeled profile.
Replace 2-phenylethyl alcohol with rose absolute
1 · Composition
2-phenylethyl alcohol 45 → 0 parts (45.0 → 0.0 per 100); rose absolute 0 → 45 parts (0.0 → 45.0 per 100); the others ×1.00.
2 · Molecules
2-phenylethyl alcohol itself leaves; with rose absolute arrive 2-phenylethyl alcohol, citronellol, geraniol and β-damascenone (no shares on record).
3 · Odour space
“spicy” 0.0 → 45.0.
4 · Perceived character
A modeled reading, not a prediction: “spicy” arriving.
5 · Dry-down
top / heart / base 0.0 / 99.9 / 0.0 → 0.0 / 99.9 / 0.0; half gone at 6.0 h (unchanged); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.
6 · Odour activity
2-phenylethyl alcohol (140 µg/kg in water, measured): ×0; rose absolute: no threshold on record; lead in water (µg/kg): geraniol.
7 · Regulation flags
The accord’s flags do not change.
Why did this change matter?
  1. rose absolute brings “spicy”, which no other component carries on record.

Version 1 against version 2

Modeled · A → B

A · Version 1 · The rose as written → B · Version 2 · Citronellol-forward

1 · What changedmodeled

  • 2-phenylethyl alcohol: 45 → 35 parts (45.0 → 35.0 per 100)
  • citronellol: 30 → 45 parts (30.0 → 45.0 per 100)
  • geraniol: 24.9 → 19.95 parts (24.9 → 20.0 per 100)
  • β-damascenone: 0.1 → 0.05 parts (0.10 → 0.05 per 100)
teaching parts · modeled

a modeled value: a stated assumption, not a measurement

teaching proportions of a teaching variant, a house interpretation for learning: modeled, not measured, not a formula, not for making

field: this accord’s record · teaching variants · version 2 · teaching parts

confidence C

2 · Molecules

2-phenylethyl alcohol itself falls; citronellol itself rises; geraniol itself falls; β-damascenone itself falls.

phenylethyl alcohol · citronellol · geraniol · β-damascenone

3 · Odour spacemodeled

“soapy” 30.0 → 45.0, “floral” 45.0 → 35.0, “honey” 45.0 → 35.0, “rose” 55.0 → 65.0, “citrus” 24.9 → 20.0 per 100 parts (the share of the accord whose components carry the word).

2-phenylethyl alcohol: descriptors · documented

2-phenylethanol | CAS 60-12-8 | Odor quality: floral, honey-like

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

field: the 2-phenylethyl alcohol record · descriptors

confidence A

citronellol: descriptors · documented

β-citronellol | CAS 106-22-9, 1117-61-9, 7540-51-4 | Odor quality: soapy, rose-like

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

field: the citronellol record · descriptors

confidence A

geraniol: descriptors · documented

geraniol | CAS 106-24-1 | Odor quality: rose-like, citrus-like

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

field: the geraniol record · descriptors

confidence A

β-damascenone: descriptors · house interpretation

the house’s own reading, labelled as such

the house’s own odour words on the page’s MOLS entry; no descriptor source is filed

field: the β-damascenone record · descriptors

confidence C

“soapy” · “floral” · “honey” · “rose” · “citrus”

4 · A modeled readingmodeled

B against A. A modeled reading, not a prediction: more “soapy” and “rose” and less “floral” and “honey”.

Generated from the movements above: a modeled reading, not a prediction and not a smell.

5 · Dry-downmodeled

Top / heart / base: 0.0 / 99.9 / 0.0 in A → 0.0 / 100.0 / 0.0 in B, per 100 parts; half the accord gone at 6.0 h → 6.0 h (modeled half-lives: top 1.5 h, heart 6 h, base 12 h); no class on record, left out: β-damascenone. The curve cannot move: every component with a class is heart.

half-lives · modeled

a modeled value: a stated assumption, not a measurement

the site constants of the evaporation simulator on /science for limonene (its Top note), Hedione (Heart) and Ambroxan (Base); “chosen for the simulator and are not measurements”

2-phenylethyl alcohol: role · documented

Floral notes, such as rose, jasmine, orange blossom, or lavender, are typically middle notes defining the “heart” of many perfumes

Kleoff et al. (2022). Synthesis of odorants in flow and their applications in perfumery · listed on the record

the review names rose among the floral heart notes

field: this accord’s record · role

confidence A

6 · Odour activitymodeled

compared in water (µg/kg): geraniol leads in both; no measured threshold on record for citronellol. Thresholds from different media or units are never compared; a teaching ratio, not a measurement of this accord.

2-phenylethyl alcohol: 140 µg/kg in water · measured

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

the retronasal threshold in the same study is 390 µg/kg (OT-1)

field: the 2-phenylethyl alcohol record · threshold

confidence A

geraniol: 1.1 µg/kg in water · measured

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

the retronasal threshold in the same study is 2.5 µg/kg (OT-1)

field: the geraniol record · threshold

confidence A

β-damascenone: 0.006 µg/kg in water · measured

Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

about six parts per trillion by mass. The Leibniz-LSB@TUM database lists the (E)-isomer (CAS 23726-93-4; this record’s PubChem CID is the (E)-isomer). The figures the site once gave (in water and in air) came from a proprietary compilation (OT-4, a source the house does not use), withdrawn as a source on 2026-09-30, and are not repeated; the database’s air values for β-damascenone are 0.002–0.004 ng/L, Blank et al. 1992 (OT-1)..

field: the β-damascenone record · threshold

confidence A

7 · Regulation flags

A flag follows presence, not dose: a smaller dose keeps the flag (several IFRA Standards on record restrict by concentration in finished products), and a teaching accord is neither a finished product nor assessed. US law: not on record. Not legal advice.

8 · Provenance

The same materials in both, so the provenance does not change. No price: nothing on this site is for sale.

Why could it smell different?
  1. Components carrying “soapy” go from 30.0 to 45.0 per 100 parts, because citronellol carries it and moves.
    documented

    β-citronellol | CAS 106-22-9, 1117-61-9, 7540-51-4 | Odor quality: soapy, rose-like

    Kreissl et al. (2022). Leibniz-LSB@TUM Odorant Database, Version 1.2 · listed on the record

    field: the citronellol record · descriptors

    confidence A

The top causes in the model, each with the record field it rests on. Modeled, not measured; not a prediction of how anything smells.

teaching accord only: not a commercial perfume formula, not for skin · the record