In short
gamma-Undecalactone, sold as aldehyde C-14 or peach aldehyde although it is a lactone, has a rich peach note.
What gamma-Undecalactone (Aldehyde C-14) smells like
gamma-Undecalactone, sold as aldehyde C-14 or peach aldehyde although it is a lactone, has a strong peach odour. Symrise describes it as strong and fruity like peach and apricot; Bedoukian as fruity and peachy with a melon-rind undertone; Lanxess as fruity, peach, creamy, fatty and apricot; Pell Wall as fruity-peach, creamy, fatty, lactonic and powerful. ChemicalBook adds ketonic and coconut. Hobbyist reviewers add a milky, slightly waxy body, and one found it more animalic than peachy.
- Leading note
- Peach
- Clear facets
- Apricot, creamy, fatty
- Faint facets
- Melon rind, coconut
- Character
- Creamy, rich, powerful, smooth
What makes gamma-Undecalactone (Aldehyde C-14) distinctive
The classic perfumery peach: powerful, creamy and fatty, with a skin-like, milky body that gives florals and chypres their velvet.
Where the descriptions disagree: One forum reviewer found it only slightly peachy and mostly animalic; supplier descriptions are peach first.
How gamma-Undecalactone (Aldehyde C-14) is used
Used in peach, apricot and fruity floral accords, in heavy florals with aldehyde C-18, and famously in classic chypres; in small amounts it gives roundness and a skin-like warmth.
Typical role: modifier (used in small amounts to change the character of a blend).
How gamma-Undecalactone (Aldehyde C-14) differs from similar materials
- gamma-Decalactone
- gamma-Decalactone is fresher and more like fruit flesh; aldehyde C-14 is fattier, waxier and longer-lasting, though sources find the difference subtle. (compared directly by a cited source)
- gamma-Nonalactone (Aldehyde C-18)
- Aldehyde C-18 is coconut first; aldehyde C-14 is peach first. Arctander notes the two are often used together. (compared directly by a cited source)
- gamma-Dodecalactone
- gamma-Dodecalactone is fattier and more buttery, used for long tenacity; C-14 is the more fruity, classic peach.
- Nectaryl
- Nectaryl is a ketone, not a lactone — a softer, very long-lasting peach-apricot with custard and coconut; C-14 is the stronger, fattier classic.
An asterisk marks a difference that a cited source states directly. The others compare the published descriptions of each material. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Formulation considerations
Strong; the "aldehyde" name is historical.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Fruity / Gourmand
- Note position
- Heart to base note
- Physical form at room temperature
- Liquid
- Also known as
- Aldehyde C-14, Peach aldehyde
- CAS number
- 104-67-6
- Molecular formula
- C11H20O2
- Molecular weight
- 184.27 g/mol
- IUPAC name
- 5-heptyloxolan-2-one
The CAS number, formula and molecular weight are taken from PubChem compound 7714, whose own record lists this CAS number; checked 19 October 2026.
Safety and compliance
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (2,205 reports): H412 harmful to aquatic life with long lasting effects (19.3% of reports); H411 toxic to aquatic life with long lasting effects (10.3% of reports). 1,536 of the reports find it does not meet the hazard criteria. Unless it is harmonised, this is the notifiers' own classification, not a binding one.
This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.
Materials it works with
-
gamma-Decalactone
Aroma chemical · Fruity / Gourmand — peach, fruity, creamy
-
gamma-Nonalactone (Aldehyde C-18)
Aroma chemical · Gourmand / Fruity — coconut, creamy, sweet, fatty
-
Osmanthus Absolute
Absolute · Floral / Fruity — apricot, leathery, floral, tea-like
gamma-Undecalactone (Aldehyde C-14) is also suggested as a partner on the pages for Benzyl Butyrate, delta-Undecalactone, Fruit Sec, gamma-Dodecalactone, Nectaryl and Veloutone.
Used in formulas and accords
Used in 18 published formulas
gamma-Undecalactone (Aldehyde C-14) is an ingredient in 8 perfume formulas, 8 accords and 2 bases in the Formula & Accord Library.
Community formulas
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about gamma-Undecalactone (Aldehyde C-14)
Is gamma-Undecalactone (Aldehyde C-14) natural or synthetic?
The molecule occurs in nature. Commercial gamma-Undecalactone (Aldehyde C-14) may be made by synthesis or obtained from natural sources, so check the supplier's specification if the distinction matters to you.
What is the CAS number of gamma-Undecalactone (Aldehyde C-14)?
104-67-6. It was checked against PubChem on 19 October 2026.
Which published formulas use gamma-Undecalactone (Aldehyde C-14)?
gamma-Undecalactone (Aldehyde C-14) is used in 18 published formulas in the RUŌOD Lab Formula & Accord Library, including Apricot Dust, Champaca Tea Room and Cherry Blossom Accord. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 7714, checked 19 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- Perflavory (The Good Scents Company) — gamma-undecalactone (with Bedoukian, Symrise and Pell Wall descriptions) — odour database.
- Lanxess — Kalama Peach Lactone — manufacturer's description.
- Basenotes — peach aldehyde C-14 (forum) — published perfumery reference.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 20 October 2026. Evidence: several independent published descriptions, which agree. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.